Field Overhaul on Lycoming 235-C2C

Strutwipe

Strutwipe

Pre-takeoff checklist
Joined
May 8, 2019
Messages
182
Display Name
Display name:
Strutwipe
Hi All,

I'm looking at a Grumman Yankee AA1 with a Lycoming 0-235-C2C with 2660 hours since new (69). My intent is to earn my PPL (No IFR instruments) and gain some flight time before moving on. The aircraft is located in my home area of Tucson, AZ. Of course this is desirable because I can actual take a look at it and fly before buying but the bottom end of the 235 is a concern. This is one of those double edge swords. Low time meaning no flight school but stagnant.

I spoke with Mark at Aircraft Engine Specialist in PHX AZ about doing a field overhaul on the engine. He hinted that it may behoove me to consider a STC for a 320 due to obsolescence and lack of support and parts. I went on FAA RGL and found STC SA4387NM to hang a 320 on the airframe but I wanted to reach out to the forum to see if anyone had a low time 235 or a good source of parts.

Does anyone else have any further insight or experience with this aircraft or engine?
 
I had an AA1B with an O-320. It was a hoot.
And, watching another local Yankee (AA1A) with an O-235 climb out of our airport at 700' field elevation on an 85* day ... I was extra glad for the O-320.
 
Another good point. Tucson is at 2420' and summer is over 100* by 11am.

Maybe Tim has an opinion?
 
The O-320 STC for the AA-1 series is popular. It will cruise and climb smartly with that engine, but it makes an already short-legged airplane even more short-legged. The AA-1X series only holds 22 gallons of usable fuel, so with the stock O-235-C2C at 6 gph cruise you better be over an airport after 3 hours. The O-320 is going to be more like 8 gph unless you throttle it way back in cruise.

I would think a quality field overhaul of an O-235-C2C would be a good deal. This is one of Lycoming's simplest and trouble free engines. It has solid (not hydraulic) tappets, which is a bit unusual. I flew an AA-1A behind the O-235 engine for 4 years and 400 hours with nary an issue. Fully loaded, it's a puny climber, but flying solo performance is pretty decent. I could plan XC trips with block speed of 125 mph (108 kt) without going full throttle, at 6 gph. The AA-1 is a bit faster. It's an amazingly fun plane to fly. I miss mine a lot, but the AA-1X just doesn't have enough payload or range for traveling with two. It's a great time- and exprerience-builder for a new pilot though. I recommend it highly!
 
If I were buying plane you list, no way would I plan to overhaul that engine. The risk of crank or case damage is too high.
 
Clip4 said:
If I were buying plane you list, no way would I plan to overhaul that engine. The risk of crank or case damage is too high.
Click to expand...
explain ? please ?
 
Tom-D said:
explain ? please ?
Click to expand...

pretty simple. The engine hasn’t been opened in 51 years and is well beyond TBO. I would not make an effort due to the risk a bad crankshaft or case problems.
 
Clip4 said:
pretty simple. The engine hasn’t been opened in 51 years and is well beyond TBO. I would not make an effort due to the risk a bad crankshaft or case problems.
Click to expand...
like any other old engine,
 
I had an AA1A for a few years. I liked it. 120MPH @ 6 gallons per hour on 87 octane auto gas. Thats 20 MPG. As said, the climb out on a hot day is a bit shallow and my legs were a bit long for it but it was good fun. I now have a AA5B Tiger and I am still flying by myself mostly except now Im burning 10 gallons per hour. Makes me wonder if I should have just kept the AA1A.
 
Clip4 said:
pretty simple. The engine hasn’t been opened in 51 years and is well beyond TBO. I would not make an effort due to the risk a bad crankshaft or case problems.
Click to expand...

This is kinda interesting

https://www.lycoming.com/sites/default/files/Lycoming Engines Exchange Engine Core Policy.pdf



Exchange engine cores that last left the Lycoming Engines factory 36 or more years ago in new, rebuilt, or overhauled condition can only be used towards the purchase of a Rebuilt or New exchange engine.
2. Exchange engine cores originally manufactured in a narrow deck or “Standard” cylinder flange model configuration that are now only manufactured in a “Wide” cylinder flange crankcase model configuration will only be accepted as an exchange engine core towards the purchase of a New or Rebuilt exchange engine.
3. All engine models referenced in the latest edition of Lycoming Service Instruction 1406 that have not been converted to accommodate the large diameter lifter will only b
 
I had an AA1 with the stc in the paperwork, but not installed. It would be ok if you had a Cheetah on hand for a parts donor. You must change out the horizontal stabilizer, add dorsal fin, change out Firewall forward, and nose gear strut, re-locate battery, and (optional) fuel tank behind seat.
Plus myriad other things. (Pretty much suspend the engine, and build the airplane around it) You gain climb performance, mabe a little bit of speed, no useful load increase, Burn more gas, making an already short legged airplane even more shorter. But, with that said, it would be a hoot to have one.
The O235 in the Yankee is an oddball. Ours started using oil at an accelerated rate, and needed new cylinders. I started looking at buying one to get the jugs, and overhaul the rest over time. Those are kinda scarce, and one from a 152, or pa38-112 will not work.
 
A good half-way point is upgrading the 108 hp -C2C into an 125 hp -L2C Sparrowhawk conversion...
STC paperwork and new pistons and jugs (same as the Cessna 152, Traumahawk) and a different prop or re-pitch yours...
Nothing hard about finding parts. Great little engine. No more or less prone to damage from disuse than any other aircraft engine.
There's an STC to put the AA5 nose strut on the AA1 series but unless you bang it on the stock strut is just fine. The place where they break is the torque tube that runs across the cabin the strut plugs into, it's glued to the fuselage sides and when THAT breaks loose you're taxi ing on your prop tips...
Wonderful little airplanes. I've owned 3. I like the way the -B model wing flys as opposed to the AA1 but thats JMPO.

Chris
 
All engines will fail. One that is high time and has been stagnant is a risk I'm not willing to take. As Bluerooster states, the -C2C is an oddball engine which increase part cost. With the short range, I just don't think it will be worth the time. Thanks all for your input.
 
Mark
You didn't say what you are looking for in an airplane or what kind of money you are willing to spend, or how much he wants for it... you should be able to find a well maintained bird with 1200-1500 SMOH for a reasonable price and you can fly right away. Want a Grumman Yankee with an 0-320? Somebody is selling one somewhere, if not today then maybe tomorrow. Keep looking and you'll find a good bird. Do the numbers, get a good prebuy inspection, and go for it.

Good luck.
 
Thanks Pete. Actually, I've been looking for a Tomahawk/150 or similar training aircraft for my PPL, advertise, and promote my product StrutWipe. The Yankee is at my home station which is very appealing. The AA1 is at a reasonable price, 19K, but putting in an additional 5K+ in part just does not make sense. With that being said, you are correct to keep looking. I have found a PA 38 that is IFR certified with GPS. The engine time is a little high at 1850 hrs but has been on oil analysis which show normal trends. All of the ADs have either been complied with or is current. So for 22K it looks like a solid Arizona bird. The pre-buy is schedule for the second weekend in Jan, so I should have it here in Tucson soon. The TH was a trainer in Virginia so you may of seen it around.
 

Attachments

  • 50356868596_e4151a6dd5_o.jpg
    50356868596_e4151a6dd5_o.jpg
    191.4 KB · Views: 16
  • 50356878161_cc9c438cf3_o.jpg
    50356878161_cc9c438cf3_o.jpg
    216.6 KB · Views: 12
You must log in or register to reply here.
Back
Top