Bondline - User contributions [en]

Replace stock O235 engine with O320-E2G AirModsNW STC

2009-02-19T01:44:30Z

Aa1bflyboy:

Bob Steward suggested I create a page here in an attempt to describe my process of performing the engine upgrade from the O235-C2C that our AA1x models came with to the more appropriate O320 engine. I started with a core that I purchased from Gil Alexander.
[[Image:O320b.jpg|200px|thumb|left|O320 core ready to ship]]
I'm told Gil did me very well in selling me this core. It's an O320-E2G, which is the stock engine for the Cheetah. This worked out best for me as I wanted to use the STC available from Ken Blackman AKA AirModsNW. There are three STCs available to choose from to perform this modification. If you are considering the upgrade gather as much info as possible on all three before making your decision. Each has its positive and negative sides. Each owner needs to weigh the pro and con of each for them-self. My decision was made on recommendations of others who had used Ken's STC and by my A&P after describing the process involved and each of the STCs. Since my particular A&P/IA had never performed an O320 conversion on a Grumman AA1x before (C&P brand yes, just never an AA1x) I wanted to go with the one that had the most documentation provided with the STC.

For the engine I chose new ECI CermiNil® Process cylinders http://www.eci.aero/pages/services_advantage.aspx. I picked Aero Engines of Winchester 540-678-1661 (ask for Tom) for the overhaul of the engine. This STC limits the HP to the stock 150HP pistons and since the crank did not pass the AD inspection, it's my understanding I would not have been allowed to use it in my engine with the 160HP pistons. I was told by several reliable source gurus on the GG that I'd never miss the 10HP. They were right; going from 108HP to 150HP has been such a dramatic increase in power it's like I'm flying and entirely new airplane. I've started uploading photos of the project as I put this article together. So keep an eye out for updates.

<center>
{| border="0" style="background:transparent;"
|-
|
||
[[Image:Testrun411.jpg|200px|thumb|left|O320 test run at Aero Engines of Winchester]]
||
[[Image:Testrun414.jpg|200px|thumb|left|O320 test run *man those pipes were loud*]]
|}
</center>
 

'''Day 1: Removal of the old O235 engine.''' Removal was a fairly simple process. It is a ''REAL'' good idea to keep track of every nut bolt and screw as well as making ''GOOD'' documentations of what wire came from where. If not just be sure to label every wire indicating what terminal it goes to. A good digital camera helps here too showing routing locations etc.

<center>
{| border="0" style="background:transparent;"
|-
|
||
[[Image:Oldmnt428.jpg‎|200px|thumb|left|O235 eng removed]]
|}
</center>

'''Day 2: Firewall prep & engine mount repair.''' I ran into a snag with the lower right engine mount extrusion. Fortunately I was not in excess of the allowable limit on this and after a day of research and sweating was able to save a ton of $$$ and at least 3 days of work.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR450.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR451.jpg|200px|thumb|left|Eng mount repair before painting firewall]]
||
[[Image:EMR471.jpg|200px|thumb|left|Bottom view of bushing]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR470.jpg|200px|thumb|left|Top of bushing]]
||
[[Image:EMR472.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR469.jpg|200px|thumb|left|Bushing in place]]
|}
</center>
 
A separate article should be written on this repair and a good procedure for inspection for this. I stripped the firewall down of dirt and paint. Since I've never been real great with a spray can I elected to have Jeff paint my firewall. Before and after photos of this appear below.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Frwlstrpd433.jpg‎|200px|thumb|left|Firewall striped]]
||
[[Image:Rdy4paint441 r1.jpg‎|200px|thumb|left|Ready to be primed]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Prmd465.jpg‎|200px|thumb|left|Firewall primed]]
||
[[Image:Pntdfrwl467.jpg‎|200px|thumb|left|Fresh paint on the firewall]]
|}
</center>
 

'''Day 3: Hanging the engine (AKA how many washers & where do those spacers go?).''' Not having a manual that has a visual for the dynafocal mount I was unsure of the placement of the spacers used with this type mount. Fortunately Shearer Aviation had the AA5x manual on file. Numerous phone calls later I did acquire the info I needed along with comparing to the AA5 drawings. The spacers are placed the same as for the AA5 and AA5A. Finding the drawing for an AA5 at the shop proved beneficial. Basically all four spacers go between the engine & mount. There are also washers that are used to shim the engine up/down or left/right. Every application is going to be different. If using new Lord mounts (which I'd highly recommend) make the spinner slightly (I used 1/4") high in relation to the nose bowl. The mounts will settle in and at that time the alignment will be correct. That is what I used and now (almost two years later) it has settled in just right. I cannot recall which Grumman Guru that one came from. Thanks to who ever did!

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Mntd486.jpg‎|200px|thumb|left|New engine mounted showing four vane oil cooler on firewall as was mounted with the O235]]
||
[[Image:Mntd489.jpg‎|200px|thumb|left|O320 mounted, right side view. Don't forget to paint the nose strut when you paint the firewall]]
||
[[Image:Spltnsbwl501.jpg‎|200px|thumb|left|A split nosebowl is a no brainer if not allready done at this time. I don't think it was necessary to use all of the screws though]]
|}
</center>
 

'''Begining of Day 3''' Somehow we missed painting the longer nose strut when we painted the firewall and baffling. Note the difference between the old (white) and the new (primed) nose strut. Here is how you get the extra prop clearance. It also can be gained by swapping out the nose fork depending on which one you have already. Also make sure your alternator brackets are in good shape. Needless to say mine were not. A call to Ken Blackman at AirMods NW had them shipped to me next day in short order. Ken is also the guru who gave me the info on how to make the engine mount repair. I guess using his STC he had a vested interest in me making it right.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Nsstrt474.jpg‎|200px|thumb|left|New and old nose strut]]
||
[[Image:Nsstrt478.jpg‎|200px|thumb|left|Close comparison of the longer nose strut to the stock one]]
||
[[Image:Altmnt475.jpg‎|200px|thumb|left|worn out alt mount]]
||
[[Image:Altmnt476.jpg‎|200px|thumb|left|Another view of alt mount]]
|}
</center>
 

'''Day 4: Baffling.'''
Using the STC from AirModsNW proved the most beneficial here. When Cliff Hansen said he spent 40 hours I thought, no way (he wasn't kidding). Having engineering drawings as well as full scale templates for the baffles proved invaluable. I photo-copied the drawings to keep the originals in good condition (thanks for that idea Paul). Using the photo-copies of the templates I was able to create baffling using the aluminum from the RV6-O320 kit (great tip from Cliff) that fit my engine perfectly (well almost, I had to modify the forward baffles some after I thought I was done; see below). Fitting to the cowling took some hours. The rear and sides went together well. Keep in mind do not apply the flex baffle to the top until you have verified the height of the upper cowl.

One of the guys helping me got the cart before the horse on this and we had to cut the baffles down after he spent quite a few hours applying the flex baffles. The two front baffles took more time than all of the other baffles combined. I'm still not pleased with how they turned out and plan on modifying or changing them out at some time in the future. My temps on 1&3 cylinders are great but I'd like to get #2&4 down about 50 degrees. It was suggested to check to make sure I don't have any flashing issues before tearing my baffles apart *again*.
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Bffl506.jpg‎|200px|thumb|left|Baffling showing 2" scat opening for oil cooler]]
||
[[Image:503.jpg‎‎|200px|thumb|left|The baffling took a long time. When Cliff told me fourty hours, I thought no way.... WAY]]
|}
</center>
 

'''Several months later:''' Replaced the oil cooler with a seven vane. The STC does require an oil cooler be installed. The four vane unit I had with the O235 did meet the minimum requirements of the STC. In the cooler spring weather when the engine was installed the oil temps were fine. However once summer came around I could not get my oil temps down to an acceptable level to me. Once again Gil pulled through for me. He had a brand new seven vane cooler just laying around the hanger that he was not using. It was actually the one he had planned on using with this engine in his RV. Since he was going with a different engine he advised he needed a different cooler and let me have it for what he paid for it years prior. I got this seven vane for less than a six vane would have cost me from Spruce. I figured more was better and have been happy with it.
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:IMG_0754.jpg‎‎|200px|thumb|left|Old & new oil coolers I think this should solve my cooling problem eh?]]
||
[[Image:IMG_0758.jpg‎‎|200px|thumb|left|Both coolers and boxes to compare]]
||
[[Image:IMG_0772.jpg‎|200px|thumb|left|Baffling showing 3" scat opening for new oil cooler]]
|}
</center>
 

I do have to put a blocking plate over the scat tube hole in the winter months or my oil never gets anywhere near minimum temps. I was able to only find 3" adapters for the scat tube at the cooler box and rear baffle. I picked them up at a boneyard in slower DE (Jenkins Airport 15N). Ken said I only would need the 2" but he also said I'd be fine with the 4 vane cooler. It must get a lot hotter in DE than WA. Old man Jenkins also had a replacement VS for the repairs when I was doing my paint. That too will be another article. I built the airbox for the cooler and did the cooler upgrade while she was down for the paint in the summer of of '07.

'''Then a while after that:''' I relocated the batery to behind the baggage compartment. When the W&B was calculated we determined 64L had gained a bit of wieght in her years. With the engine swap she had her CG fwd a good bit and to keep her inside the envelope I had you fly with a 50# weight in the baggage compartment. We had to place a placard on the panel stating this also. This never caused a problem flying alone but with a passenger it easily could have put me over GW. Ken Blackman supplied me with most of the hardware and some photos of the job being done by another AA1x. Copies of some 337s were included. The job wasn't as hard as I thought it was going to be. I would like to make an easy access panel in the rear of the baggage compartment for servicing the battery. Although using the Concord RG cell reduces the requirement of adding water so less service required. Pics of that for another day.

File:IMG 0772.jpg

2009-02-19T01:21:36Z

Aa1bflyboy:

Rear baffle cut for the 3" scat tube adapter

File:IMG 0772.jpg

2009-02-19T01:20:45Z

Aa1bflyboy: Think this will give me the cooling I need?

Think this will give me the cooling I need?

File:IMG 0758.jpg

2009-02-19T01:19:11Z

Aa1bflyboy: Both coolers and boxes to compare

Both coolers and boxes to compare

File:IMG 0757.jpg

2009-02-19T01:18:00Z

Aa1bflyboy: New 7 vane cooler

New 7 vane cooler

File:IMG 0756.jpg

2009-02-19T01:17:14Z

Aa1bflyboy: New 7 vane cooler

New 7 vane cooler

File:IMG 0755.jpg

2009-02-19T01:16:29Z

Aa1bflyboy: Old and new coolers

Old and new coolers

File:IMG 0754.jpg

2009-02-19T01:15:21Z

Aa1bflyboy: Old & new oil coolers

Old & new oil coolers

Replace stock O235 engine with O320-E2G AirModsNW STC

2009-02-19T01:07:26Z

Aa1bflyboy:

Bob Steward suggested I create a page here in an attempt to describe my process of performing the engine upgrade from the O235-C2C that our AA1x models came with to the more appropriate O320 engine. I started with a core that I purchased from Gil Alexander.
[[Image:O320b.jpg|200px|thumb|left|O320 core ready to ship]]
I'm told Gil did me very well in selling me this core. It's an O320-E2G, which is the stock engine for the Cheetah. This worked out best for me as I wanted to use the STC available from Ken Blackman AKA AirModsNW. There are three STCs available to choose from to perform this modification. If you are considering the upgrade gather as much info as possible on all three before making your decision. Each has its positive and negative sides. Each owner needs to weigh the pro and con of each for them-self. My decision was made on recommendations of others who had used Ken's STC and by my A&P after describing the process involved and each of the STCs. Since my particular A&P/IA had never performed an O320 conversion on a Grumman AA1x before (C&P brand yes, just never an AA1x) I wanted to go with the one that had the most documentation provided with the STC.

For the engine I chose new ECI CermiNil® Process cylinders http://www.eci.aero/pages/services_advantage.aspx. I picked Aero Engines of Winchester 540-678-1661 (ask for Tom) for the overhaul of the engine. This STC limits the HP to the stock 150HP pistons and since the crank did not pass the AD inspection, it's my understanding I would not have been allowed to use it in my engine with the 160HP pistons. I was told by several reliable source gurus on the GG that I'd never miss the 10HP. They were right; going from 108HP to 150HP has been such a dramatic increase in power it's like I'm flying and entirely new airplane. I've started uploading photos of the project as I put this article together. So keep an eye out for updates.

<center>
{| border="0" style="background:transparent;"
|-
|
||
[[Image:Testrun411.jpg|200px|thumb|left|O320 test run at Aero Engines of Winchester]]
||
[[Image:Testrun414.jpg|200px|thumb|left|O320 test run *man those pipes were loud*]]
|}
</center>
 

'''Day 1: Removal of the old O235 engine.''' Removal was a fairly simple process. It is a ''REAL'' good idea to keep track of every nut bolt and screw as well as making ''GOOD'' documentations of what wire came from where. If not just be sure to label every wire indicating what terminal it goes to. A good digital camera helps here too showing routing locations etc.

<center>
{| border="0" style="background:transparent;"
|-
|
||
[[Image:Oldmnt428.jpg‎|200px|thumb|left|O235 eng removed]]
|}
</center>

'''Day 2: Firewall prep & engine mount repair.''' I ran into a snag with the lower right engine mount extrusion. Fortunately I was not in excess of the allowable limit on this and after a day of research and sweating was able to save a ton of $$$ and at least 3 days of work.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR450.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR451.jpg|200px|thumb|left|Eng mount repair before painting firewall]]
||
[[Image:EMR471.jpg|200px|thumb|left|Bottom view of bushing]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR470.jpg|200px|thumb|left|Top of bushing]]
||
[[Image:EMR472.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR469.jpg|200px|thumb|left|Bushing in place]]
|}
</center>
 
A separate article should be written on this repair and a good procedure for inspection for this. I stripped the firewall down of dirt and paint. Since I've never been real great with a spray can I elected to have Jeff paint my firewall. Before and after photos of this appear below.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Frwlstrpd433.jpg‎|200px|thumb|left|Firewall striped]]
||
[[Image:Rdy4paint441 r1.jpg‎|200px|thumb|left|Ready to be primed]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Prmd465.jpg‎|200px|thumb|left|Firewall primed]]
||
[[Image:Pntdfrwl467.jpg‎|200px|thumb|left|Fresh paint on the firewall]]
|}
</center>
 

'''Day 3: Hanging the engine (AKA how many washers & where do those spacers go?).''' Not having a manual that has a visual for the dynafocal mount I was unsure of the placement of the spacers used with this type mount. Fortunately Shearer Aviation had the AA5x manual on file. Numerous phone calls later I did acquire the info I needed along with comparing to the AA5 drawings. The spacers are placed the same as for the AA5 and AA5A. Finding the drawing for an AA5 at the shop proved beneficial. Basically all four spacers go between the engine & mount. There are also washers that are used to shim the engine up/down or left/right. Every application is going to be different. If using new Lord mounts (which I'd highly recommend) make the spinner slightly (I used 1/4") high in relation to the nose bowl. The mounts will settle in and at that time the alignment will be correct. That is what I used and now (almost two years later) it has settled in just right. I cannot recall which Grumman Guru that one came from. Thanks to who ever did!

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Mntd486.jpg‎|200px|thumb|left|New engine mounted showing four vane oil cooler on firewall as was mounted with the O235]]
||
[[Image:Mntd489.jpg‎|200px|thumb|left|O320 mounted, right side view. Don't forget to paint the nose strut when you paint the firewall]]
||
[[Image:Spltnsbwl501.jpg‎|200px|thumb|left|A split nosebowl is a no brainer if not allready done at this time. I don't think it was necessary to use all of the screws though]]
|}
</center>
 

'''Begining of Day 3''' Somehow we missed painting the longer nose strut when we painted the firewall and baffling. Note the difference between the old (white) and the new (primed) nose strut. Here is how you get the extra prop clearance. It also can be gained by swapping out the nose fork depending on which one you have already. Also make sure your alternator brackets are in good shape. Needless to say mine were not. A call to Ken Blackman at AirMods NW had them shipped to me next day in short order. Ken is also the guru who gave me the info on how to make the engine mount repair. I guess using his STC he had a vested interest in me making it right.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Nsstrt474.jpg‎|200px|thumb|left|New and old nose strut]]
||
[[Image:Nsstrt478.jpg‎|200px|thumb|left|Close comparison of the longer nose strut to the stock one]]
||
[[Image:Altmnt475.jpg‎|200px|thumb|left|worn out alt mount]]
||
[[Image:Altmnt476.jpg‎|200px|thumb|left|Another view of alt mount]]
|}
</center>
 

'''Day 4: Baffling.'''
Using the STC from AirModsNW proved the most beneficial here. When Cliff Hansen said he spent 40 hours I thought, no way (he wasn't kidding). Having engineering drawings as well as full scale templates for the baffles proved invaluable. I photo-copied the drawings to keep the originals in good condition (thanks for that idea Paul). Using the photo-copies of the templates I was able to create baffling using the aluminum from the RV6-O320 kit (great tip from Cliff) that fit my engine perfectly (well almost, I had to modify the forward baffles some after I thought I was done; see below). Fitting to the cowling took some hours. The rear and sides went together well. Keep in mind do not apply the flex baffle to the top until you have verified the height of the upper cowl.

One of the guys helping me got the cart before the horse on this and we had to cut the baffles down after he spent quite a few hours applying the flex baffles. The two front baffles took more time than all of the other baffles combined. I'm still not pleased with how they turned out and plan on modifying or changing them out at some time in the future. My temps on 1&3 cylinders are great but I'd like to get #2&4 down about 50 degrees. It was suggested to check to make sure I don't have any flashing issues before tearing my baffles apart *again*.
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Bffl506.jpg‎|200px|thumb|left|Baffling showing 2" scat opening for oil cooler]]
||
[[Image:503.jpg‎‎|200px|thumb|left|The baffling took a long time. When Cliff told me fourty hours, I thought no way.... WAY]]
|}
</center>
 

'''Several months later:''' Replaced the oil cooler with a seven vane. The STC does require an oil cooler be installed. The four vane unit I had with the O235 did meet the minimum requirements of the STC. In the cooler spring weather when the engine was installed the oil temps were fine. However once summer came around I could not get my oil temps down to an acceptable level to me. Once again Gil pulled through for me. He had a brand new seven vane cooler just laying around the hanger that he was not using. It was actually the one he had planned on using with this engine in his RV. Since he was going with a different engine he advised he needed a different cooler and let me have it for what he paid for it years prior. I got this seven vane for less than a six vane would have cost me from Spruce. I figgured more was better and have been happy with it. I do have to put a blocking plate over the scat tube hole in the winter months or my oil never gets anywhere near minimum temps. I was able to only find 3" adapters for the scat tube at the cooler box and rear baffle. I picked them up at a boneyard in slower DE (Jenkins Airport 15N). Ken said I only would need the 2" but he also said I'd be fine with the 4 vane cooler. It must get a lot hotter in DE than WA. Old man Jenkins also had a replacement VS for the repairs when I was doing my paint. That too will be another article. I built the airbox for the cooler and did the cooler upgrade while she was down for the paint in the summer of of '07.

'''Then a while after that:''' I relocated the batery to behind the baggage compartment. When the W&B was calculated we determined 64L had gained a bit of wieght in her years. With the engine swap she had her CG fwd a good bit and to keep her inside the envelope I had you fly with a 50# weight in the baggage compartment. We had to place a placard on the panel stating this also. This never caused a problem flying alone but with a passenger it easily could have put me over GW. Ken Blackman supplied me with most of the hardware and some photos of the job being done by another AA1x. Copies of some 337s were included. The job wasn't as hard as I thought it was going to be. I would like to make an easy access panel in the rear of the baggage compartment for servicing the battery. Although using the Concord RG cell reduces the requirement of adding water so less service required.

Replace stock O235 engine with O320-E2G AirModsNW STC

2009-02-19T00:42:29Z

Aa1bflyboy:

Bob Steward suggested I create a page here in an attempt to describe my process of performing the engine upgrade from the O235-C2C that our AA1x models came with to the more appropriate O320 engine. I started with a core that I purchased from Gil Alexander.
[[Image:O320b.jpg|200px|thumb|left|O320 core ready to ship]]
I'm told Gil did me very well in selling me this core. It's an O320-E2G, which is the stock engine for the Cheetah. This worked out best for me as I wanted to use the STC available from Ken Blackman AKA AirModsNW. There are three STCs available to choose from to perform this modification. If you are considering the upgrade gather as much info as possible on all three before making your decision. Each has its positive and negative sides. Each owner needs to weigh the pro and con of each for them-self. My decision was made on recommendations of others who had used Ken's STC and by my A&P after describing the process involved and each of the STCs. Since my particular A&P/IA had never performed an O320 conversion on a Grumman AA1x before (C&P brand yes, just never an AA1x) I wanted to go with the one that had the most documentation provided with the STC.

For the engine I chose new ECI CermiNil® Process cylinders http://www.eci.aero/pages/services_advantage.aspx. I picked Aero Engines of Winchester 540-678-1661 (ask for Tom) for the overhaul of the engine. This STC limits the HP to the stock 150HP pistons and since the crank did not pass the AD inspection, it's my understanding I would not have been allowed to use it in my engine with the 160HP pistons. I was told by several reliable source gurus on the GG that I'd never miss the 10HP. They were right; going from 108HP to 150HP has been such a dramatic increase in power it's like I'm flying and entirely new airplane. I've started uploading photos of the project as I put this article together. So keep an eye out for updates.

<center>
{| border="0" style="background:transparent;"
|-
|
||
[[Image:Testrun411.jpg|200px|thumb|left|O320 test run at Aero Engines of Winchester]]
||
[[Image:Testrun414.jpg|200px|thumb|left|O320 test run *man those pipes were loud*]]
|}
</center>
 

'''Day 1: Removal of the old O235 engine.''' Removal was a fairly simple process. It is a ''REAL'' good idea to keep track of every nut bolt and screw as well as making ''GOOD'' documentations of what wire came from where. If not just be sure to label every wire indicating what terminal it goes to. A good digital camera helps here too showing routing locations etc.

<center>
{| border="0" style="background:transparent;"
|-
|
||
[[Image:Oldmnt428.jpg‎|200px|thumb|left|O235 eng removed]]
|}
</center>

'''Day 2: Firewall prep & engine mount repair.''' I ran into a snag with the lower right engine mount extrusion. Fortunately I was not in excess of the allowable limit on this and after a day of research and sweating was able to save a ton of $$$ and at least 3 days of work.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR450.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR451.jpg|200px|thumb|left|Eng mount repair before painting firewall]]
||
[[Image:EMR471.jpg|200px|thumb|left|Bottom view of bushing]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR470.jpg|200px|thumb|left|Top of bushing]]
||
[[Image:EMR472.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR469.jpg|200px|thumb|left|Bushing in place]]
|}
</center>
 
A separate article should be written on this repair and a good procedure for inspection for this. I stripped the firewall down of dirt and paint. Since I've never been real great with a spray can I elected to have Jeff paint my firewall. Before and after photos of this appear below.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Frwlstrpd433.jpg‎|200px|thumb|left|Firewall striped]]
||
[[Image:Rdy4paint441 r1.jpg‎|200px|thumb|left|Ready to be primed]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Prmd465.jpg‎|200px|thumb|left|Firewall primed]]
||
[[Image:Pntdfrwl467.jpg‎|200px|thumb|left|Fresh paint on the firewall]]
|}
</center>
 

'''Day 3: Hanging the engine (AKA how many washers & where do those spacers go?).''' Not having a manual that has a visual for the dynafocal mount I was unsure of the placement of the spacers used with this type mount. Fortunately Shearer Aviation had the AA5x manual on file. Numerous phone calls later I did acquire the info I needed along with comparing to the AA5 drawings. The spacers are placed the same as for the AA5 and AA5A. Finding the drawing for an AA5 at the shop proved beneficial. Basically all four spacers go between the engine & mount. There are also washers that are used to shim the engine up/down or left/right. Every application is going to be different. If using new Lord mounts (which I'd highly recommend) make the spinner slightly (I used 1/4") high in relation to the nose bowl. The mounts will settle in and at that time the alignment will be correct. That is what I used and now (almost two years later) it has settled in just right. I cannot recall which Grumman Guru that one came from. Thanks to who ever did!

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Mntd486.jpg‎|200px|thumb|left|New engine mounted showing four vane oil cooler on firewall as was mounted with the O235]]
||
[[Image:Mntd489.jpg‎|200px|thumb|left|O320 mounted, right side view. Don't forget to paint the nose strut when you paint the firewall]]
||
[[Image:Spltnsbwl501.jpg‎|200px|thumb|left|A split nosebowl is a no brainer if not allready done at this time. I don't think it was necessary to use all of the screws though]]
|}
</center>
 

'''Begining of Day 3''' Somehow we missed painting the longer nose strut when we painted the firewall and baffling. Note the difference between the old (white) and the new (primed) nose strut. Here is how you get the extra prop clearance. It also can be gained by swapping out the nose fork depending on which one you have already. Also make sure your alternator brackets are in good shape. Needless to say mine were not. A call to Ken Blackman at AirMods NW had them shipped to me next day in short order. Ken is also the guru who gave me the info on how to make the engine mount repair. I guess using his STC he had a vested interest in me making it right.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Nsstrt474.jpg‎|200px|thumb|left|New and old nose strut]]
||
[[Image:Nsstrt478.jpg‎|200px|thumb|left|Close comparison of the longer nose strut to the stock one]]
||
[[Image:Altmnt475.jpg‎|200px|thumb|left|worn out alt mount]]
||
[[Image:Altmnt476.jpg‎|200px|thumb|left|Another view of alt mount]]
|}
</center>
 

'''Day 4: Baffling.'''
Using the STC from AirModsNW proved the most beneficial here. When Cliff Hansen said he spent 40 hours I thought, no way (he wasn't kidding). Having engineering drawings as well as full scale templates for the baffles proved invaluable. I photo-copied the drawings to keep the originals in good condition (thanks for that idea Paul). Using the photo-copies of the templates I was able to create baffling using the aluminum from the RV6-O320 kit (great tip from Cliff) that fit my engine perfectly (well almost, I had to modify the forward baffles some after I thought I was done; see below). Fitting to the cowling took some hours. The rear and sides went together well. Keep in mind do not apply the flex baffle to the top until you have verified the height of the upper cowl.

One of the guys helping me got the cart before the horse on this and we had to cut the baffles down after he spent quite a few hours applying the flex baffles. The two front baffles took more time than all of the other baffles combined. I'm still not pleased with how they turned out and plan on modifying or changing them out at some time in the future. My temps on 1&3 cylinders are great but I'd like to get #2&4 down about 50 degrees. It was suggested to check to make sure I don't have any flashing issues before tearing my baffles apart *again*.
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Bffl506.jpg‎|200px|thumb|left|Baffling showing 2" scat opening for oil cooler]]
||
[[Image:503.jpg‎‎|200px|thumb|left|The baffling took a long time. When Cliff told me fourty hours, I thought no way.... WAY]]
|}
</center>
 

'''Several months later:''' Replaced the oil cooler with a seven vane.

'''Then a while after that:''' I relocated the batery to behind the baggage compartment. When the W&B was calculated we determined 64L had gained a bit of wieght in her years. With the engine swap she had her CG fwd a good bit and to keep her inside the envelope I had you fly with a 50# weight in the baggage compartment. We had to place a placard on the panel stating this also. This never caused a problem flying alone but with a passenger it easily could have put me over GW. Ken Blackman supplied me with most of the hardware and some photos of the job being done by another AA1x. Copies of some 337s were included. The job wasn't as hard as I thought it was going to be. I would like to make an easy access panel in the rear of the baggage compartment for servicing the battery. Although using the Concord RG cell reduces the requirement of adding water so less service required.

File:Spltnsbwl501.jpg

2009-02-19T00:10:45Z

Aa1bflyboy:

A split nosebowl is a no brainer if not already done at this time. I don't think it was necessary to use all of the screws though.

Replace stock O235 engine with O320-E2G AirModsNW STC

2009-02-18T22:57:48Z

Aa1bflyboy:

Bob Steward suggested I create a page here in an attempt to describe my process of performing the engine upgrade from the O235-C2C that our AA1x models came with to the more appropriate O320 engine. I started with a core that I purchased from Gil Alexander.
[[Image:O320b.jpg|200px|thumb|left|O320 core ready to ship]]
I'm told Gil did me very well in selling me this core. It's an O320-E2G, which is the stock engine for the Cheetah. This worked out best for me as I wanted to use the STC available from Ken Blackman AKA AirModsNW. There are three STCs available to choose from to perform this modification. If you are considering the upgrade gather as much info as possible on all three before making your decision. Each has its positive and negative sides. Each owner needs to weigh the pro and con of each for them-self. My decision was made on recommendations of others who had used Ken's STC and by my A&P after describing the process involved and each of the STCs. Since my particular A&P/IA had never performed an O320 conversion on a Grumman AA1x before (C&P brand yes, just never an AA1x) I wanted to go with the one that had the most documentation provided with the STC.
For the engine I chose new ECI CermiNil® Process cylinders http://www.eci.aero/pages/services_advantage.aspx. I picked Aero Engines of Winchester 540-678-1661 (ask for Tom) for the overhaul of the engine. This STC limits the HP to the stock 150HP pistons and since the crank did not pass the AD inspection, it's my understanding I would not have been allowed to use it in my engine with the 160HP pistons. I was told by several reliable source gurus on the GG that I'd never miss the 10HP. They were right; going from 108HP to 150HP has been such a dramatic increase in power it's like I'm flying and entirely new airplane. I've started uploading photos of the project as I put this article together. So keep an eye out for updates.

'''Day 1: Removal of the old O235 engine.''' Removal was a fairly simple process. It is a ''REAL'' good idea to keep track of every nut bolt and screw as well as making ''GOOD'' documentations of what wire came from where. If not just be sure to label every wire indicating what terminal it goes to. A good digital camera helps here too showing routing locations etc.

'''Day 2: Firewall prep & engine mount repair.''' I ran into a snag with the lower right engine mount extrusion. Fortunately I was not in excess of the allowable limit on this and after a day of research and sweating was able to save a ton of $$$ and at least 3 days of work.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR450.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR451.jpg|200px|thumb|left|Eng mount repair before painting firewall]]
||
[[Image:EMR471.jpg|200px|thumb|left|Bottom view of bushing]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR470.jpg|200px|thumb|left|Top of bushing]]
||
[[Image:EMR472.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR469.jpg|200px|thumb|left|Bushing in place]]
|}
</center>
 
A separate article should be written on this repair and a good procedure for inspection for this. I stripped the firewall down of dirt and paint. Since I've never been real great with a spray can I elected to have Jeff paint my firewall. Before and after photos of this appear below.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Oldmnt428.jpg‎|200px|thumb|left|O235 eng removed]]
||
[[Image:Frwlstrpd433.jpg‎|200px|thumb|left|Firewall striped]]
||
[[Image:Rdy4paint441 r1.jpg‎|200px|thumb|left|Ready to be primed]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Prmd465.jpg‎|200px|thumb|left|Firewall primed]]
||
[[Image:Pntdfrwl467.jpg‎|200px|thumb|left|Fresh paint on the firewall]]
|}
</center>
 

'''Day 3: Hanging the engine (AKA how many washers & where do those spacers go?).''' Not having a manual that has a visual for the dynafocal mount I was unsure of the placement of the spacers used with this type mount. Fortunately Shearer Aviation had the AA5x manual on file. Numerous phone calls later I did acquire the info I needed along with comparing to the AA5 drawings. The spacers are placed the same as for the AA5 and AA5A. Finding the drawing for an AA5 at the shop proved beneficial. Basically all four spacers go between the engine & mount. There are also washers that are used to shim the engine up/down or left/right. Every application is going to be different. If using new Lord mounts (which I'd highly recommend) make the spinner slightly (I used 1/4") high in relation to the nose bowl. The mounts will settle in and at that time the alignment will be correct. That is what I used and now (almost two years later) it has settled in just right. I cannot recall which Grumman Guru that one came from. Thanks to who ever did!

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Mntd486.jpg‎|200px|thumb|left|New engine mounted showing four vane oil cooler on firewall as was mounted with the O235]]
||
[[Image:Mntd489.jpg‎|200px|thumb|left|O320 mounted, right side view. Don't forget to paint the nose strut when you paint the firewall]]
||
[[Image:Spltnsbwl501.jpg‎|200px|thumb|left|A split nosebowl is a no brainer if not allready done at this time. I don't think it was necessary to use all of the screws though]]
|}
</center>
 

'''Begining of Day 3''' Somehow we missed painting the longer nose strut when we painted the firewall and baffling. Note the difference between the old (white) and the new (primed) nose strut. Here is how you get the extra prop clearance. It also can be gained by swapping out the nose fork depending on which one you have already. Also make sure your alternator brackets are in good shape. Needless to say mine were not. A call to Ken Blackman at AirMods NW had them shipped to me next day in short order. Ken is also the guru who gave me the info on how to make the engine mount repair. I guess using his STC he had a vested interest in me making it right.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Nsstrt474.jpg‎|200px|thumb|left|New and old nose strut]]
||
[[Image:Nsstrt478.jpg‎|200px|thumb|left|Close comparison of the longer nose strut to the stock one]]
||
[[Image:Altmnt475.jpg‎|200px|thumb|left|worn out alt mount]]
||
[[Image:Altmnt476.jpg‎|200px|thumb|left|Another view of alt mount]]
|}
</center>
 

'''Day 4: Baffling.'''
Using the STC from AirModsNW proved the most beneficial here. When Cliff Hansen said he spent 40 hours I thought, no way (he wasn't kidding). Having engineering drawings as well as full scale templates for the baffles proved invaluable. I photo-copied the drawings to keep the originals in good condition (thanks for that idea Paul). Using the photo-copies of the templates I was able to create baffling using the aluminum from the RV6-O320 kit (great tip from Cliff) that fit my engine perfectly (well almost, I had to modify the forward baffles some after I thought I was done; see below). Fitting to the cowling took some hours. The rear and sides went together well. Keep in mind do not apply the flex baffle to the top until you have verified the height of the upper cowl.

One of the guys helping me got the cart before the horse on this and we had to cut the baffles down after he spent quite a few hours applying the flex baffles. The two front baffles took more time than all of the other baffles combined. I'm still not pleased with how they turned out and plan on modifying or changing them out at some time in the future. My temps on 1&3 cylinders are great but I'd like to get #2&4 down about 50 degrees. It was suggested to check to make sure I don't have any flashing issues before tearing my baffles apart *again*.
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Bffl506.jpg‎|200px|thumb|left|Baffling showing 2" scat opening for oil cooler]]
||
[[Image:503.jpg‎‎|200px|thumb|left|The baffling took a long time. When Cliff told me fourty hours, I thought no way.... WAY]]
|}
</center>
 

'''Several months later:''' Replaced the oil cooler with a seven vane.

'''Then a while after that:''' I relocated the batery to behind the baggage compartment. When the W&B was calculated we determined 64L had gained a bit of wieght in her years. With the engine swap she had her CG fwd a good bit and to keep her inside the envelope I had you fly with a 50# weight in the baggage compartment. We had to place a placard on the panel stating this also. This never caused a problem flying alone but with a passenger it easily could have put me over GW. Ken Blackman supplied me with most of the hardware and some photos of the job being done by another AA1x. Copies of some 337s were included. The job wasn't as hard as I thought it was going to be. I would like to make an easy access panel in the rear of the baggage compartment for servicing the battery. Although using the Concord RG cell reduces the requirement of adding water so less service required.

GrummanMechanics

2009-02-18T22:36:01Z

Aa1bflyboy:

There are frequent requests on the Grumman Gang for Grumman savvy mechanics. The hope is that we may build a database here, similar to the concept of TripAdvisor. The list should be organized by State, and then by field. Under state, insert the field in alphanumeric order, and then insert your mechanic. Please comment good or bad, but try to be fair. The reality is that someone may be excellent, but an owner may have a bad experience. That's fine, and expected. Just be straight, and at least the reader can make more informed decisions. Additionally, please inject a link to your user page after your comments. This will afford some sort of accountability, as well as give readers a source to query if needed.

'''Policy Change for this page. The intent is to solicit comments and personal recommendations, unlike the rest of Bondline, which is intended to be factual or instructive in the comments, with the content being neutral to individuals or companies. To claim your comments, good or bad, on this page, you must identify yourself with a link to your user page, and begin and end your comments with quotation marks, to separate factual information (name, location, phone numbers, etc.) from your personal experiences, praise, or criticism. Everyone is welcome to add to this page, but do not edit other contributor's quoted comments.'''

Link each of your comments to your user page, e.g. [[User:Bob_Steward|Bob Steward]], like so:

:<nowiki>[[User:Bob_Steward|Bob Steward]]</nowiki>

To learn how to format your entries, look at one of the other entries or read the [http://meta.wikimedia.org/wiki/Help:Wikitext Wikitext Help].

----

'''ARKANSAS'''

D&T Paint, Mena, AR
:[[User:Scoffey|Stephen Coffey]]: "In February, 2008, they painted my airplane, and did an acceptable $3,500 single color job. Communication is horrible. Yes, there are details I would have done differently myself, but didn't have time. I would NOT have them do anything unless you set up a $500 to start, $1000 after you strip it and send me pictures, yaddah yaddah type of plan."

TwelveStone Aviation, 479-841-1836, Springdale, AR
:[[User:Scott_Jernigan|Scott Jernigan]], February, 2008: "John Gearhart has been working on my Cheetah for 10 years now. He was involved in the HyperCheetah conversion as well. John is a very good mechanic who refuses to cut corners, but also knows the difference between required and recommended."

----

'''CALIFORNIA'''

Mike McCarthy, Spider's Aircraft, MYF (San Diego Area)
:[[User:Scoffey|Stephen Coffey]]: "In May, 2007, I was looking at an airplane in the San Diego area, and Mike did a prebuy. He did it almost immediately, and called after he found a couple of items, giving me his impression. This decision saved me a good deal of money as I eliminated the airplane before he spent a ton of time on it. I really appreciated that. He seemed very type-knowlegeable."

----

'''DELAWARE'''

Jim Russell, N74 Chorman Airport - Farmington, DE (about a dozen clicks south of Dover AFB)
:[[User:aa1bflyboy|Steve Roberts]]: "In the summer of '07 I wanted to paint 64L. After speaking to Jim and finding out about his back log, I took his recommendation of just painting the parts of my plane that needed painting (only about 25%). I like the kind of businessman who is willing to give away work in hopes that when you are in need of his specific services you will come back. He is geared up to do one plane at a time. The work he has done is superb. There are several Grumman owners in the MidAtlantic Region who have had their planes painted there. I know of one that is on the cover of the Star. Contact me directly and I can point you to the guy who did the paint at 58M."

----
'''GEORGIA'''

PDK (Atlanta):

Steve Sirmer, AP/IA 404-788-3616
:[[User:Scoffey|Stephen Coffey]], February, 2009: "I was referred to Steve in late 2008. Nice guy, very reasonable, and has helped out with that 'needed this week' item for which it didn't make sense for Bob Steward to run over from Alabama. Seems knowlegable and very honest from my limited dealings. Definitely an option."

[[User:Bob_Steward|Bob Steward]], AP/IA
:[[User:Scoffey|Stephen Coffey]], February, 2009: "Experience over 2007-2009. There are just times you don't want anyone else to work on your airplane, if you live in the southeast. If I lived in Birmingham, nobody else ever WOULD work on my airplane. Due to the travel, small things don't make sense to have him travel over, but for most things I absolutely recommend Bob. The job gets done right, and you learn a whole lot in the process. We've installed a new engine, R&R wings, fuel tank work, swapped fuses for breakers, replaced spinner bulkhead, all kinds of things in a short period of time."

Mark Clowdus, AP
:[[User:Scoffey|Stephen Coffey]], February, 2009: "I have occasionally used Mark for two airplanes over the past few years. Mark is thorough, but I've come to question some of his comments. On two airplanes at prebuy, he noted a rotten alternator belt. One of those had been replaced with new 3 months earlier! I've had mixed results, as have others on field. I requested an owner assisted annual at one time, and was turned down. He has insisted that my airplane, despite being 30 years old, needs 12-inch numbers. There are just better options available."

----

'''MARYLAND'''

Roger Robinson A&P/IA, Cecil Aero, 58M (Cecil County Airport)
:[[User:aa1bflyboy|Steve Roberts]]: "Roger is a very knowledgeable A&P/IA. Retired from Delta now he has been maintaining numerous Grumman type AC for many years. He is willing to allow owner assisted maintenance or drop it off and pick it up when she is ready. Roger worked with me and my painter when I wanted to paint 'just the parts that needed paint.'"

----

'''MISSOURI'''

1H0 (Creve Coeur Airport)
Jaime LeBlanc, AP/IA
:[[User:Bkamen|Ben Kamen]], February, 2009: "Jaime's a crazy cajun who used to work for TWA and has been painting and fixing airplanes for decades. A real craftsman whose prices are reasonable. He knows Grummans as he works on both 2 and 4 seaters regularly. (He usually fixes a few paint jobs from Mena, AR every year too) He's pretty laid back (read: "sometimes slow" with getting the work done. Sometimes it's because his schedule is hectic, sometimes it's due to weather (painting is a touchy thing as we know and he's a perfectionist)), but he gets the job done and the results are well worth it. He did the paint on my 74' AA-1B in 2004, but we had a lot of fixing to do on the plane and everything came out very nice. He also repaired the fiberglass on my front nosewheel and 2 years later you still can't tell."

----

'''PENNSYLVANIA'''

Jay Shearer A&P/IA, Shearer Aviation, 9D4 (Deck Airport)
:[[User:aa1bflyboy|Steve Roberts]]: "Jay is a very knowledgeable A&P/IA. Has been maintaining numerous Grumman type AC for many years. He is willing to allow owner assisted maintenance or drop it off and pick it up when she is ready. Jay worked with me when I upgraded to the O320. I also had Jay sign off for other work such as Xevision HID light and a Whelen strobe kit. No pencil whipping from this shop."

Ben Travis A&P/IA, Smart Avionics, 9D4 (Deck Airport)
:[[User:aa1bflyboy|Steve Roberts]]: "Ben and his crew at Deck worked with me on my panel upgrade. Like Jay, he allowed me to owner assist when I did this work. He also worked with me when I installed the Superclock and FP-5L."

----

'''WASHINGTON'''

SHN (Shelton, WA)

Harold Haynes, AP/IA
:[[User:Scoffey|Stephen Coffey]]: "In Nov 2007 I bought an airplane that Harold's team had been maintaining. I cannot comment on working with Harold, but there seemed to be a LOT of things unaddressed in the airplane that I now own, and had been under his care for 10 years. I know this is somewhat typical, as I've owned several airplanes, but this one was a bit more disappointing than normal. This may be at the behest of the owner, but I feel that at least some of it should have prevented labeling log books with 'found to be in airworthy condition.'"

Olympic Air
:[[User:Scoffey|Stephen Coffey]]: "In November, 2007, They did the prebuy on my airplane. They did not want to do a wobble test, and talked me out of it. That cost me about 20 grand. They did not notice that the outboard wing section on the left side had been replaced, and unlogged. Fortunately I found the owner from 1974 and resolved this to the satisfaction of the guys I reluctantly contacted at the FSDO (dumb move, by the way). This is noticeable because of the purple glue in a '72 airplane, which I feel a Grumman savvy mechanic who actually inspected the airplane would have noticed. Essentially, I'm quite sure that the list of items to check I had sent was not so thoroughly checked. I'd travel the plane for another mechanic as opposed to using these guys."

User:Aa1bflyboy

2009-02-18T21:56:36Z

Aa1bflyboy:

OK, so I got a nice start on the engine swap but I never created a page about who I am (duh, I guess you want my name too huh).

Steve Roberts, private pilot 2004, my first plane and probably my last as she fits all of my needs. To pay for this I get to play with America's largest electric train set. I have no control over which train is on which track. I do get to control the power for the trains though. It's like working with ATC but for trains. Other hobbies besides flying include motorcycles, wheelin' in my Jeep TJ, recreational shooting (1911 variants are my favorite).

TW signoff as I was this () close to buying Andy Elliot's TD 481HY.

N641HY Currently based at ILG Wilmington DE

[[Image:Th 64Ltaila.jpg|200px|thumb|left|Larger sunset photo at Queen City. One of the nicest shot I have of 64L]]

I got started flying late in life compared to most other pilots I know. 64L is my first plane and although she was in very nice condition when I bought her, like many other Grumman owner/pilots the need to improve her from the beginning was there. I attended my 1st AYA convention in 2004 at Baraboo WI the summer after I bought her. I soloed in her five days before I left for the convention. I flew with Dave Scull in his Tiger for what turned into one of many more flights in our wonderful type AC. Later that year I got my check ride in 64L. After my trip to OSH with my cousin I got to thinking hard about an O320 upgrade. Once I flew with Paul Tolini in his O320 powered AA1C I realized how much she (and I) really needed the O320 upgrade.

The pages within here will show what improvements I've made to her since I've owned her. The updates are not being posted here chronologically as I started off building the page for the engine swap.
The photo to the left is after the engine upgrade and before the paint.
----

'''The Airplane'''

1973 AA1B (Trainer)

A little over 4200 hours as of 2/2009

New paint and changed N number 8/2007 (only about 25% really)

MOH w/O320 upgrade 4/2007

Battery relocated behind baggage compartment

Whelen three position strobes

XeVision HID landing light

IFR capable panel (for when I take the time to get that ticket)
VFR- For now...

EI Superclock (won it in Baraboo 2004)

EI FP-5L fuel totalizer

DMA wheel pants

Aux tanks (5 gal each wing)

Interior all that's left to do

Replace stock O235 engine with O320-E2G AirModsNW STC

2009-02-13T18:52:04Z

Aa1bflyboy:

Bob Steward suggested I create a page here in an attempt to describe my process of performing the engine upgrade from the O235-C2C that our AA1x models came with to the more appropriate O320 engine. I started with a core that I purchased from Gil Alexander.
[[Image:O320b.jpg|200px|thumb|left|O320 core ready to ship]]
I'm told Gil did me very well in selling me this core. It's an O320-E2G, which is the stock engine for the Cheetah. This worked out best for me as I wanted to use the STC available from Ken Blackman AKA AirModsNW. There are three STCs available to choose from to perform this modification. If you are considering the upgrade gather as much info as possible on all three before making your decision. Each has its positive and negative sides. Each owner needs to weigh the pro and con of each for them-self. My decision was made on recommendations of others who had used Ken's STC and by my A&P after describing the process involved and each of the STCs. Since my particular A&P/IA had never performed an O320 conversion on a Grumman AA1x before (C&P brand yes, just never an AA1x) I wanted to go with the one that had the most documentation provided with the STC.
For the engine I chose new ECI CermiNil® Process cylinders <http://www.eci.aero/pages/services_advantage.aspx>. I picked Aero Engines of Winchester 540-678-1661 (ask for Tom) for the overhaul of the engine. This STC limits the HP to the stock 150HP pistons and since the crank did not pass the AD inspection, it's my understanding I would not have been allowed to use it in my engine with the 160HP pistons. I was told by several reliable source gurus on the GG that I'd never miss the 10HP. They were right; going from 108HP to 150HP has been such a dramatic increase in power it's like I'm flying and entirely new airplane. I've started uploading photos of the project as I put this article together. So keep an eye out for updates.

'''Day 1: Removal of the old O235 engine.''' Removal was a fairly simple process. It is a ''REAL'' good idea to keep track of every nut bolt and screw as well as making ''GOOD'' documentations of what wire came from where. If not just be sure to label every wire indicating what terminal it goes to. A good digital camera helps here too showing routing locations etc.

'''Day 2: Firewall prep & engine mount repair.''' I ran into a snag with the lower right engine mount extrusion. Fortunately I was not in excess of the allowable limit on this and after a day of research and sweating was able to save a ton of $$$ and at least 3 days of work.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR450.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR451.jpg|200px|thumb|left|Eng mount repair before painting firewall]]
||
[[Image:EMR471.jpg|200px|thumb|left|Bottom view of bushing]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR470.jpg|200px|thumb|left|Top of bushing]]
||
[[Image:EMR472.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR469.jpg|200px|thumb|left|Bushing in place]]
|}
</center>
 
A separate article should be written on this repair and a good procedure for inspection for this. I stripped the firewall down of dirt and paint. Since I've never been real great with a spray can I elected to have Jeff paint my firewall. Before and after photos of this will appear here shortly.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Oldmnt428.jpg‎|200px|thumb|left|O235 eng removed]]
||
[[Image:Frwlstrpd433.jpg‎|200px|thumb|left|Firewall striped]]
||
[[Image:Rdy4paint441 r1.jpg‎|200px|thumb|left|Ready to be primed]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Prmd465.jpg‎|200px|thumb|left|Firewall primed]]
||
[[Image:Pntdfrwl467.jpg‎|200px|thumb|left|Fresh paint on the firewall]]
|}
</center>
 

'''Day 3: Hanging the engine (AKA how many washers & where do those spacers go?).''' Not having a manual that has a visual for the dynafocal mount I was unsure of the placement of the spacers used with this type mount. Fortunately Shearer Aviation had the AA5x manual on file. Numerous phone calls later I did acquire the info I needed along with comparing to the AA5 drawings. The spacers are placed the same as for the AA5 and AA5A. Finding the drawing for an AA5 at the shop proved beneficial. Basically all four spacers go behind the mount. There are also washers that are used to shim the engine up/down or left/right. Every application is going to be different. If using new Lord mounts (which I'd highly recommend) make the spinner slightly (I used 1/4") high in relation to the nose bowl. The mounts will settle in and at that time the alignment will be correct. That is what I used and now (almost two years later) it has settle in just right. I cannot recall which Grumman Guru that one came from.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Mntd486.jpg‎|200px|thumb|left|New engine mounted showing four vane oil cooler on firewall as was mounted with the O235]]
||
[[Image:Mntd489.jpg‎|200px|thumb|left|O320 mounted, right side view. Don't forget to paint the nose strut when you paint the firewall]]
||
[[Image:Spltnsbwl501.jpg‎|200px|thumb|left|A split nosebowl is a no brainer if not allready done at this time. I don't think it was necessary to use all of the screws though]]
|}
</center>
 

'''Begining of Day 3''' Somehow we missed painting the longer nose strut when we painted the firewall and baffling. Note the difference between the old (white) and the new (primed) nose strut. Here is how you get the extra prop clearance. It also can be gained by swapping out the nose fork depending on which one you have already. Also make sure your alternator brackets are in good shape. Needless to say mine were not. A call to Ken Blackman at AirMods NW had them shipped to me next day in short order. Ken is also the guru who gave me the info on how to make the engine mount repair.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Nsstrt474.jpg‎|200px|thumb|left|New and old nose strut]]
||
[[Image:Nsstrt478.jpg‎|200px|thumb|left|Close comparison of the longer nose strut to the stock one]]
||
[[Image:Altmnt475.jpg‎|200px|thumb|left|worn out alt mount]]
||
[[Image:Altmnt476.jpg‎|200px|thumb|left|Another view of alt mount]]
|}
</center>
 

'''Day 4: Baffling.'''
Using the STC from AirModsNW proved the most beneficial here. When Cliff Hansen said he spent 40 hours I thought, no way (he wasn't kidding). Having engineering drawings as well as full scale templates for the baffles proved invaluable. I photo-copied the drawings to keep the originals in good condition (thanks for that idea Paul). Using the photo-copies of the templates I was able to create baffling using the aluminum from the RV6-O320 kit (great tip from Cliff) that fit my engine perfectly (well almost, I had to modify the forward baffles some after I thought I was done; see below). Fitting to the cowling took some hours. The rear and sides went together well. Keep in mind do not apply the flex baffle to the top until you have verified the height of the upper cowl.

One of the guys helping me got the cart before the horse on this and we had to cut the baffles down after he spent quite a few hours applying the flex baffles. The two front baffles took more time than all of the other baffles combined. I'm still not pleased with how they turned out and plan on modifying or changing them out at some time in the future. My temps on 1&3 cylinders are great but I'd like to get #2&4 down about 50 degrees. It was suggested to check to make sure I don't have any flashing issues before tearing my baffles apart *again*.
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Bffl506.jpg‎|200px|thumb|left|Baffling showing 2" scat opening for oil cooler]]
||
[[Image:503.jpg‎‎|200px|thumb|left|The baffling took a long time. When Cliff told me fourty hours, I thought no way.... WAY]]
|}
</center>
 

'''Several months later:''' Replaced the oil cooler with a seven vane.

'''Then a while after that:''' I relocated the batery to behind the baggage compartment. When the W&B was calculated we determined 64L had gained a bit of wieght in her years. With the engine swap she had her CG fwd a good bit and to keep her inside the envelope I had you fly with a 50# weight in the baggage compartment. We had to place a placard on the panel stating this also. This never caused a problem flying alone but with a passenger it easily could have put me over GW. Ken Blackman supplied me with most of the hardware and some photos of the job being done by another AA1x. Copies of some 337s were included. The job wasn't as hard as I thought it was going to be. I would like to make an easy access panel in the rear of the baggage compartment for servicing the battery. Although using the Concord RG cell reduces the requirement of adding water so less service required.

User talk:Steve Williams

2009-02-13T15:14:27Z

Aa1bflyboy:

Steve,

You took out my comma! Isn't it better grammar with the comma in place?

--Bob

Steve, gee you want my name too? LOL

-Steve Roberts

User:Aa1bflyboy

2009-02-13T15:10:58Z

Aa1bflyboy:

OK, so I got a nice start on the engine swap but I never created a page about who I am (duh, I guess you want my name too huh).

Steve Roberts, private pilot 2004, my first plane and probably my last as she fits all of my needs. To pay for this I get to play with America's largest electric train set. I have no control over which train is on which track. I do get to control the power for the trains though. It's like working with ATC but for trains. Other hobbies besides flying include motorcycles, wheelin' in my Jeep TJ, recreational shooting (1911 variants are my favorite).

TW signoff as I was this () close to buying Andy Elliot's TD 481HY.

N641HY Currently based at ILG Wilmington DE

[[Image:Th 64Ltaila.jpg|200px|thumb|left|Larger sunset photo at Queen City. One of the nicest shot I have of 64L]]

I got started flying late in life compared to most other pilots I know. 64L is my first plane and although she was in very nice condition when I bought her, like many other Grumman owner/pilots the need to improve her from the beginning was there. I attended my 1st AYA convention in 2004 at Baraboo WI the summer after I bought her. I soloed in her five days before I left for the convention. I flew with Dave Scull in his Tiger for what turned into one of many more flights in our wonderful type AC. Later that year I got my check ride in 64L. After my trip to OSH with my cousin I got to thinking hard about an O320 upgrade. Once I flew with Paul Tolini in his O320 powered AA1C I realized how much she (and I) really needed the O320 upgrade.

The pages within here will show what improvements I've made to her since I've owned her. The updates are not being posted here chronologically as I started off building the page for the engine swap.

----

'''The Airplane'''

1973 AA1B (Trainer)

A little over 4200 hours as of 2/2009

New paint and changed N number 8/2007 (only about 25% really)

MOH w/O320 upgrade 4/2007

Battery relocated behind baggage compartment

Whelen three position strobes

XeVision HID landing light

IFR panel (for when I take the time to get that ticket)

EI Superclock (won it in Baraboo 2004)

EI FP-5L fuel totalize

DMA wheel pants

Aux tanks (5 gal each wing)

Interior all that's left to do

VFR- For now anyway...

User:Aa1bflyboy

2009-02-13T15:08:16Z

Aa1bflyboy:

OK, so I got a nice start on the engine swap but I never created a page about who I am (duh, I guess you want my name too huh).

Steve Roberts, private pilot 2004, my first plane and probably my last as she fits all of my needs. To pay for this I get to play with America's largest electric train set. I have no control over which train is on which track. I do get to control the power for the trains though. It's like working with ATC but for trains. Other hobbies besides flying include motorcycles, wheelin' in my Jeep TJ, recreational shooting (1911 variants are my favorite).

TW signoff as I was this () close to buying Andy Elliot's TD 481HY.

N641HY Currently based at ILG Wilmington DE

----

'''The Airplane'''

1973 AA1B (Trainer)

A little over 4200 hours as of 2/2009

New paint and changed N number 8/2007 (only about 25% really)

MOH w/O320 upgrade 4/2007

Battery relocated behind baggage compartment

Whelen three position strobes

XeVision HID landing light

IFR panel (for when I take the time to get that ticket)

EI Superclock (won it in Baraboo 2004)

EI FP-5L fuel totalize

DMA wheel pants

Aux tanks (5 gal each wing)

Interior all that's left to do

VFR- For now anyway...

[[Image:Th 64Ltaila.jpg|200px|thumb|left|Larger sunset photo at Queen City. One of the nicest shot I have of 64L]]
----
I got started flying late in life compared to most other pilots I know. 64L is my first plane and although she was in very nice condition when I bought her, like many other Grumman owner/pilots the need to improve her from the beginning was there. I attended my 1st AYA convention in 2004 at Baraboo WI the summer after I bought her. I soloed in her five days before I left for the convention. I flew with Dave Scull in his Tiger for what turned into one of many more flights in our wonderful type AC. Later that year I got my check ride in 64L. After my trip to OSH with my cousin I got to thinking hard about an O320 upgrade. Once I flew with Paul Tolini in his O320 powered AA1C I realized how much she (and I) really needed the O320 upgrade.

The pages within here will show what improvements I've made to her since I've owned her. The updates are not being posted here chronologically as I started off building the page for the engine swap.

User:Aa1bflyboy

2009-02-13T15:03:21Z

Aa1bflyboy:

OK, so I got a nice start on the engine swap but I never created a page about who I am (duh, I guess you want my name too huh).

Steve Roberts, private pilot 2004, my first plane and probably my last as she fits all of my needs. To pay for this I get to play with America's largest electric train set. I have no control over whch train is on which track. I do get to control the power for the trains though. It's like working with ATC but for trains. Other hobies besides flying include motorcycles, wheelin' in my Jeep TJ, recreational shooting (1911 variants are my favorite).

TW signoff as I was this () close to buying Andy Elliot's TD 481HY.

N641HY Currently based at ILG Wilmington DE

The Airplane

1973 AA1B (Trainer)

a little over 4200 hours as of 2/2009

New paint and changed N number 8/2007 (only about 25% really)

MOH w/O320 upgrade 4/2007

Battery relocated behind baggage compartment

Whelen three position strobes

XeVision HID landing light

IFR panel (for when I take the time to get that ticket)

EI Superclock (won it in Baraboo 2004)

EI FP-5L fuel totalizer

DMA wheel pants

Aux tanks (5 gal each wing)

Interior all that's left to do

VFR- For now anyway...

[[Image:Th 64Ltaila.jpg|200px|thumb|left|Larger sunset photo at Queen City. One of the nicest shot I have of 64L]]
----
I got started flying late in life compared to most other pilots I know. 64L is my first plane and although she was in very nice condition when I bought her, like many other Grumman owner/pilots the need to improve her from the beginning was there. I attended my 1st AYA convention in 2004 at Baraboo WI the summer after I bought her. I soloed in her five days before I left for the convention. I flew with Dave Scull in his Tiger for what turned into one of many more flights in our wonderful type AC. Later that year I got my check ride in 64L. After my trip to OSH with my cousin I got to thinking hard about an O320 upgrade. Once I flew with Paul Tolini in his O320 powered AA1C I realized how much she (and I) really needed the O320 upgrade.

The pages within here will show what improvements I've made to her since I've owned her. The updates are not being posted here chronologically as I started off building the page for the engine swap.

User:Aa1bflyboy

2009-02-12T18:19:11Z

Aa1bflyboy: User page update

OK so I got a nice start on the engine swap but I never created a page about who I am.
[[Image:Th 64Ltaila.jpg|200px|thumb|left|Larger sunset photo at Queen City. One of the nicest shot I have of 64L]]
----
I got started flying late in life compared to most other pilots I know. 64L is my first plane and although she was in very nice condition when I bought her, like many other Grumman owner/pilots the need to improve her from the beginning was there. I attended my 1st AYA convention in 2004 at Baraboo WI the summer after I bought her. I soloed in her five days before I left for the convention. I flew in Dave Scull's Tiger for what turned into one of many more flights in our wonderful type AC. Later that year I got my check ride in 64L. After my trip to OSH with my cousin I got to thinking hard about an O320 upgrade. Once I flew with Paul Tolini in his O320 powered AA1C I realized how much she (and I) really needed the O320 upgrade.

The pages within here will show what improvements I've made to her since I've owned her. The updates are not being posted here chronologically as I started off building the page for the engine swap.

User:Aa1bflyboy

2009-02-12T18:06:12Z

Aa1bflyboy:

OK so I got a nice start on the engine swap but I never created a page about who I am.
----
[[Image:Th 64Ltaila.jpg|200px|thumb|left|Larger sunset photo at Queen City. One of the nicest shot I have of 64L]]

File:Th 64Ltaila.jpg

2009-02-12T17:51:58Z

Aa1bflyboy: uploaded a new version of "Image:Th 64Ltaila.jpg": Larger sunset photo at Queen City. One of the nicest shot I have of 64L

One of the nicest shots I have of 64L. This was taken at Queen City one Friday evening when I flew up to meet Intis dinner.

File:CA14EXTB.jpg

2009-02-12T17:48:28Z

Aa1bflyboy:

Friday night dinner at Queen City summer after engine swap

File:CA14EXTB.jpg

2009-02-12T17:45:11Z

Aa1bflyboy: Sunset at Queen City summer after engine swap

Sunset at Queen City summer after engine swap

File:NWbshdrwng.jpg

2009-02-12T17:24:00Z

Aa1bflyboy: Drawing of nose wheel bushing

Drawing of nose wheel bushing

File:ThNWbsh.jpg

2009-02-12T17:15:08Z

Aa1bflyboy: Drawing of bushing for nose wheel

Drawing of bushing for nose wheel

File:Th CA14EXTB.jpg

2009-02-12T17:12:54Z

Aa1bflyboy: Another shot of that day at Queen City.

Another shot of that day at Queen City.

File:Th 64Ltaila.jpg

2009-02-12T17:11:20Z

Aa1bflyboy: One of the nicest shots I have of 64L. This was taken at Queen City one Friday evening when I flew up to meet Intis dinner.

One of the nicest shots I have of 64L. This was taken at Queen City one Friday evening when I flew up to meet Intis dinner.

File:Newbird810.jpg

2009-02-12T17:08:03Z

Aa1bflyboy: No more 9664L now she is 641HY

No more 9664L now she is 641HY

File:O235 436.jpg

2009-02-12T17:05:02Z

Aa1bflyboy: Old O235-C2C eng

Old O235-C2C eng

User:Aa1bflyboy

2009-02-12T17:03:20Z

Aa1bflyboy: New page: OK so I got a nice start on the engine swap but I never created a page about who I am. ----

OK so I got a nice start on the engine swap but I never created a page about who I am.
----

Replace stock O235 engine with O320-E2G AirModsNW STC

2009-02-12T03:38:59Z

Aa1bflyboy:

Bob Steward suggested I create a page here in an attempt to describe my process of performing the engine upgrade from the O235-C2C that our AA1x models came with to the more appropriate O320 engine. I started with a core that I purchased from Gil Alexander.
||[[Image:O320b.jpg|200px|thumb|left|O320 core ready to ship]]||
I'm told Gil did me very well in selling me this core. It's an O320-E2G, which is the stock engine for the Cheetah. This worked out best for me as I wanted to use the STC available from Ken Blackman AKA AirModsNW. There are three STCs available to choose from to perform this modification. If you are considering the upgrade gather as much info as possible on all three before making your decision. Each has its positive and negative sides. Each owner needs to weigh the pro and con of each for them-self. My decision was made on recommendations of others who had used Ken's STC and by my A&P after describing the process involved and each of the STCs. Since my particular A&P/IA had never performed an O320 conversion on a Grumman AA1x before (C&P brand yes, just never an AA1x) I wanted to go with the one that had the most documentation provided with the STC.
For the engine I chose new ECI CermiNil® Process cylinders <http://www.eci.aero/pages/services_advantage.aspx>. I picked Aero Engines of Winchester 540-678-1661 (ask for Tom) for the overhaul of the engine. This STC limits the HP to the stock 150HP pistons and since the crank did not pass the AD inspection, it's my understanding I would not have been allowed to use it in my engine with the 160HP pistons. I was told by several reliable source gurus on the GG that I'd never miss the 10HP. They were right; going from 108HP to 150HP has been such a dramatic increase in power it's like I'm flying and entirely new airplane. I've started uploading photos of the project as I put this article together. So keep an eye out for updates.

'''Day 1: Removal of the old O235 engine.''' Removal was a fairly simple process. It is a ''REAL'' good idea to keep track of every nut bolt and screw as well as making ''GOOD'' documentations of what wire came from where. If not just be sure to label every wire indicating what terminal it goes to. A good digital camera helps here too showing routing locations etc.

'''Day 2: Firewall prep & engine mount repair.''' I ran into a snag with the lower right engine mount extrusion. Fortunately I was not in excess of the allowable limit on this and after a day of research and sweating was able to save a ton of $$$ and at least 3 days of work.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR450.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR451.jpg|200px|thumb|left|Eng mount repair before painting firewall]]
||
[[Image:EMR471.jpg|200px|thumb|left|Bottom view of bushing]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR470.jpg|200px|thumb|left|Top of bushing]]
||
[[Image:EMR472.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR469.jpg|200px|thumb|left|Bushing in place]]
|}
</center>
 
A separate article should be written on this repair and a good procedure for inspection for this. I stripped the firewall down of dirt and paint. Since I've never been real great with a spray can I elected to have Jeff paint my firewall. Before and after photos of this will appear here shortly.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Oldmnt428.jpg‎|200px|thumb|left|O235 eng removed]]
||
[[Image:Frwlstrpd433.jpg‎|200px|thumb|left|Firewall striped]]
||
[[Image:Rdy4paint441 r1.jpg‎|200px|thumb|left|Ready to be primed]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Prmd465.jpg‎|200px|thumb|left|Firewall primed]]
||
[[Image:Pntdfrwl467.jpg‎|200px|thumb|left|Fresh paint on the firewall]]
|}
</center>
 

'''Day 3: Hanging the engine (AKA how many washers & where do those spacers go?).''' Not having a manual that has a visual for the dynafocal mount I was unsure of the placement of the spacers used with this type mount. Fortunately Shearer Aviation had the AA5x manual on file. Numerous phone calls later I did acquire the info I needed along with comparing to the AA5 drawings. The spacers are placed the same as for the AA5 and AA5A. Finding the drawing for an AA5 at the shop proved beneficial. Basically all four spacers go behind the mount. There are also washers that are used to shim the engine up/down or left/right. Every application is going to be different. If using new Lord mounts (which I'd highly recommend) make the spinner slightly (I used 1/4") high in relation to the nose bowl. The mounts will settle in and at that time the alignment will be correct. That is what I used and now (almost two years later) it has settle in just right. I cannot recall which Grumman Guru that one came from.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Mntd486.jpg‎|200px|thumb|left|New engine mounted showing four vane oil cooler on firewall as was mounted with the O235]]
||
[[Image:Mntd489.jpg‎|200px|thumb|left|O320 mounted, right side view. Don't forget to paint the nose strut when you paint the firewall]]
||
[[Image:Spltnsbwl501.jpg‎|200px|thumb|left|A split nosebowl is a no brainer if not allready done at this time. I don't think it was necessary to use all of the screws though]]
|}
</center>
 

'''Begining of Day 3''' Somehow we missed painting the longer nose strut when we painted the firewall and baffling. Note the difference between the old (white) and the new (primed) nose strut. Here is how you get the extra prop clearance. It also can be gained by swapping out the nose fork depending on which one you have already. Also make sure your alternator brackets are in good shape. Needless to say mine were not. A call to Ken Blackman at AirMods NW had them shipped to me next day in short order. Ken is also the guru who gave me the info on how to make the engine mount repair.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Nsstrt474.jpg‎|200px|thumb|left|New and old nose strut]]
||
[[Image:Nsstrt478.jpg‎|200px|thumb|left|Close comparison of the longer nose strut to the stock one]]
||
[[Image:Altmnt475.jpg‎|200px|thumb|left|worn out alt mount]]
||
[[Image:Altmnt476.jpg‎|200px|thumb|left|Another view of alt mount]]
|}
</center>
 

'''Day 4: Baffling.'''
Using the STC from AirModsNW proved the most beneficial here. When Cliff Hansen said he spent 40 hours I thought, no way (he wasn't kidding). Having engineering drawings as well as full scale templates for the baffles proved invaluable. I photo-copied the drawings to keep the originals in good condition (thanks for that idea Paul). Using the photo-copies of the templates I was able to create baffling using the aluminum from the RV6-O320 kit (great tip from Cliff) that fit my engine perfectly (well almost, I had to modify the forward baffles some after I thought I was done; see below). Fitting to the cowling took some hours. The rear and sides went together well. Keep in mind do not apply the flex baffle to the top until you have verified the height of the upper cowl.

One of the guys helping me got the cart before the horse on this and we had to cut the baffles down after he spent quite a few hours applying the flex baffles. The two front baffles took more time than all of the other baffles combined. I'm still not pleased with how they turned out and plan on modifying or changing them out at some time in the future. My temps on 1&3 cylinders are great but I'd like to get #2&4 down about 50 degrees. It was suggested to check to make sure I don't have any flashing issues before tearing my baffles apart *again*.
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Bffl506.jpg‎|200px|thumb|left|Baffling showing 2" scat opening for oil cooler]]
||
[[Image:503.jpg‎‎|200px|thumb|left|The baffling took a long time. When Cliff told me fourty hours, I thought no way.... WAY]]
|}
</center>
 

'''Several months later:''' Replaced the oil cooler with a seven vane.

Replace stock O235 engine with O320-E2G AirModsNW STC

2009-02-12T03:30:41Z

Aa1bflyboy: Final edition for today 2/11/09

Bob Steward suggested I create a page here in an attempt to describe my process of performing the engine upgrade from the O235-C2C that our AA1x models came with to the more appropriate O320 engine. I started with a core that I purchased from Gil Alexander.
||[[Image:O320b.jpg|200px|thumb|left|O320 core ready to ship]]
I'm told Gil did me very well in selling me this core. It's an O320-E2G, which is the stock engine for the Cheetah. This worked out best for me as I wanted to use the STC available from Ken Blackman AKA AirModsNW. There are three STCs available to choose from to perform this modification. If you are considering the upgrade gather as much info as possible on all three before making your decision. Each has its positive and negative sides. Each owner needs to weigh the pro and con of each for them-self. My decision was made on recommendations of others who had used Ken's STC and by my A&P after describing the process involved and each of the STCs. Since my particular A&P/IA had never performed an O320 conversion on a Grumman AA1x before (C&P brand yes, just never an AA1x) I wanted to go with the one that had the most documentation provided with the STC.
For the engine I chose new ECI CermiNil® Process cylinders <http://www.eci.aero/pages/services_advantage.aspx>. I picked Winchester-Aero Services for the overhaul of the engine. This STC limits the HP to the stock 150HP pistons and since the crank did not pass the AD inspection, it's my understanding I would not have been allowed to use it in my engine with the 160HP pistons. I was told by several reliable source gurus on the GG that I'd never miss the 10HP. They were right; going from 108HP to 150HP has been such a dramatic increase in power it's like I'm flying and entirely new airplane. I've started uploading photos of the project as I put this article together. So keep an eye out for updates.

'''Day 1: Removal of the old O235 engine.''' Removal was a fairly simple process. It is a ''REAL'' good idea to keep track of every nut bolt and screw as well as making ''GOOD'' documentations of what wire came from where. If not just be sure to label every wire indicating what terminal it goes to. A good digital camera helps here too showing routing locations etc.

'''Day 2: Firewall prep & engine mount repair.''' I ran into a snag with the lower right engine mount extrusion. Fortunately I was not in excess of the allowable limit on this and after a day of research and sweating was able to save a ton of $$$ and at least 3 days of work.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR450.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR451.jpg|200px|thumb|left|Eng mount repair before painting firewall]]
||
[[Image:EMR471.jpg|200px|thumb|left|Bottom view of bushing]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:EMR470.jpg|200px|thumb|left|Top of bushing]]
||
[[Image:EMR472.jpg|200px|thumb|left|Eng mount repair]]
||
[[Image:EMR469.jpg|200px|thumb|left|Bushing in place]]
|}
</center>
 
A separate article should be written on this repair and a good procedure for inspection for this. I stripped the firewall down of dirt and paint. Since I've never been real great with a spray can I elected to have Jeff paint my firewall. Before and after photos of this will appear here shortly.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Oldmnt428.jpg‎|200px|thumb|left|O235 eng removed]]
||
[[Image:Frwlstrpd433.jpg‎|200px|thumb|left|Firewall striped]]
||
[[Image:Rdy4paint441 r1.jpg‎|200px|thumb|left|Ready to be primed]]
|}
</center>
<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Prmd465.jpg‎|200px|thumb|left|Firewall primed]]
||
[[Image:Pntdfrwl467.jpg‎|200px|thumb|left|Fresh paint on the firewall]]
|}
</center>
 

'''Day 3: Hanging the engine (AKA how many washers & where do those spacers go?).''' Not having a manual that has a visual for the dynafocal mount I was unsure of the placement of the spacers used with this type mount. Fortunately Shearer Aviation had the AA5x manual on file. Numerous phone calls later I did acquire the info I needed along with comparing to the AA5 drawings. The spacers are placed the same as for the AA5 and AA5A. Finding the drawing for an AA5 at the shop proved beneficial. Basically all four spacers go behind the mount. There are also washers that are used to shim the engine up/down or left/right. Every application is going to be different. If using new Lord mounts (which I'd highly recommend) make the spinner slightly (I used 1/4") high in relation to the nose bowl. The mounts will settle in and at that time the alignment will be correct. That is what I used and now (almost two years later) it has settle in just right. I cannot recall which Grumman Guru that one came from.

<center>
{| border="0" style="background:transparent;"
|-
|
[[Image:Mntd486.jpg‎|200px|thumb|left|New engine mounted showing four vane oil cooler on firewall as was mounted with the O235]]
||
[[Image:Mntd489.jpg‎|200px|thumb|left|O320 mounted, right side view. Don't forget to paint the nose strut when you paint the firewall]]
||
[[Image:Spltnsbwl501.jpg‎|200px|thumb|left|A split nosebowl is a no brainer if not allready done at this time. I don't think it was necessary to use all of the screws though]]
|}
</center>
 

'''Begining of Day 3''' Somehow we missed painting the longer nose strut when we painted the firewall and baffling. Note the difference between the old (white) and the new (primed) nose strut. Here is how you get the extra prop clearnce. It also can be gained by swaping out the nose fork depending on which one you have already. Also make sure your alternator brackets are in good shape. Needless to say mine were not.

<center>
{| border="0" style="background:transparent;"
|-
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[[Image:Nsstrt474.jpg‎|200px|thumb|left|New and old nose strut]]
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[[Image:Nsstrt478.jpg‎|200px|thumb|left|Close comparison of the longer nose strut to the stock one]]
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[[Image:Altmnt475.jpg‎|200px|thumb|left|worn out alt mount]]
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[[Image:Altmnt476.jpg‎|200px|thumb|left|Another view of alt mount]]
|}
</center>
 

'''Day 4: Baffling.'''
Using the STC from AirModsNW proved the most beneficial here. When Cliff Hansen said he spent 40 hours I thought, no way (he wasn't kidding). Having engineering drawings as well as full scale templates for the baffles proved invaluable. I photo-copied the drawings to keep the originals in good condition (thanks for that idea Paul). Using the photo-copies of the templates I was able to create baffling using the aluminum from the RV6-O320 kit (great tip from Cliff) that fit my engine perfectly (well almost, I had to modify the forward baffles some after I thought I was done; see below). Fitting to the cowling took some hours. The rear and sides went together well. Keep in mind do not apply the flex baffle to the top until you have verified the height of the upper cowl.

One of the guys helping me got the cart before the horse on this and we had to cut the baffles down after he spent quite a few hours applying the flex baffles. The two front baffles took more time than all of the other baffles combined. I'm still not pleased with how they turned out and plan on modifying or changing them out at some time in the future. My temps on 1&3 cylinders are great but I'd like to get #2&4 down about 50 degrees. It was suggested to check to make sure I don't have any flashing issues before tearing my baffles apart *again*.
<center>
{| border="0" style="background:transparent;"
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[[Image:Bffl506.jpg‎|200px|thumb|left|Baffling showing 2" scat opening for oil cooler]]
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[[Image:503.jpg‎‎|200px|thumb|left|The baffling took a long time. When Cliff told me fourty hours, I thought no way.... WAY]]
|}
</center>
 

'''Several months later:''' Replaced the oil cooler with a seven vane.

Replace stock O235 engine with O320-E2G AirModsNW STC

2009-02-12T02:03:21Z

Aa1bflyboy:

File:EMR472.jpg

2009-02-12T01:54:34Z

Aa1bflyboy: Eng mount repair

Eng mount repair

File:ADIZ2008Nov.pdf

2009-02-12T01:14:24Z

Aa1bflyboy: FAA Course Cert for the ADIZ

FAA Course Cert for the ADIZ

File:Bffl506.jpg

2009-02-12T01:11:50Z

Aa1bflyboy: Baffling showing 2" scat opening for oil cooler

Baffling showing 2" scat opening for oil cooler

File:503.jpg

2009-02-12T01:10:19Z

Aa1bflyboy: The baffling took a long time. When Cliff told me fourty hours, I thought no way.... WAY!!!

The baffling took a long time. When Cliff told me fourty hours, I thought no way.... WAY!!!

File:Spltnsbwl501.jpg

2009-02-12T01:07:34Z

Aa1bflyboy: A split nosebowl is a no brainer if not allready done at this time. I don't think it was necessary to use all of the screws though.

A split nosebowl is a no brainer if not allready done at this time. I don't think it was necessary to use all of the screws though.

File:Mntd489.jpg

2009-02-12T01:05:09Z

Aa1bflyboy: O320 mounted, right side view. Don't forget to paint the nose strut when you paint the firewall.

O320 mounted, right side view. Don't forget to paint the nose strut when you paint the firewall.

File:Mntd486.jpg

2009-02-12T01:02:51Z

Aa1bflyboy: New engine mounted showing four vane oil cooler on firewall as was mounted with the O235

New engine mounted showing four vane oil cooler on firewall as was mounted with the O235

File:Nsstrt478.jpg

2009-02-12T01:00:00Z

Aa1bflyboy: Close comparison of the longer nose strut to the stock one

Close comparison of the longer nose strut to the stock one

File:Altmnt476.jpg

2009-02-12T00:58:44Z

Aa1bflyboy: Another view of alt mount

Another view of alt mount

File:Altmnt475.jpg

2009-02-12T00:57:32Z

Aa1bflyboy: worn out alt mount

worn out alt mount

File:Nsstrt474.jpg

2009-02-12T00:56:26Z

Aa1bflyboy: New and old nose strut

New and old nose strut

File:Pntdfrwl467.jpg

2009-02-12T00:54:59Z

Aa1bflyboy: Fresh paint on the firewall

Fresh paint on the firewall

File:Prmd465.jpg

2009-02-12T00:53:36Z

Aa1bflyboy: Firewall primed

Firewall primed

File:Rdy4paint441 r1.jpg

2009-02-12T00:51:47Z

Aa1bflyboy: Ready to be primed

Ready to be primed

File:Frwlstrpd433.jpg

2009-02-12T00:50:46Z

Aa1bflyboy: Firewall striped

Firewall striped

File:Oldmnt428.jpg

2009-02-12T00:49:31Z

Aa1bflyboy: O235 eng removed

O235 eng removed