DIY engine rebuild

[Aerco]

I have a question that may sound ignorant, but my Aeronca project is the first certified airplane I ever owned and worked on, having mostly been involved with homebuilts and ultralights.

How much of the work of rebuilding an engine can be done by myself under the supervision of an A&P (not an A&P with IA)?

I am very familiar with engines of all kinds and have rebuilt many automotive, motorcycles and other types, including working on Ranger and Gypsy engines. I know exactly what is required from a technical point of view, but what about the legalities?

I have some experienced A&P friends whom I can call on to supervise, but I am not sure at what point an IA comes in.

Any help appreciated.

[pmanton]

A&P can supervise these small engines.

Paul
N2426E
N1431A
2AZ1
(A&P IA)

[Aerco]

Sorry, this ended up in the wrong category - should have been engine/powerplant section.

[Nathan K. Hammond]

For an overhaul, an A/P is all that's required. As far as how much work you can do: that comes down to the relationship with your A/P. If its good and he likes your work, he might sign the logs after you've done everything.

nkh

[Champ Dreamer]

Peter,

I overhauled my C-85 and would encourage you to do so also. I Got a copy of the original Continental overhaul manual, a video done in the 30's or 40's (e-bay) and another video by mattituck. Studied all carefully, made notes and a written assembly sequence sheet. Discussed ewverything carefully with A&P supervisor before and during assembly. (He helped put cases together). Of course, you are really not overhauling anything, just assembling parts overhauled by others. I am much like you, have dabbled with engines all my life. I am currently working on my A&P. You will find the experience rewarding and valuable; if anything ever goes wrong, you have the upper hand in diagnosing.

BTW: Drug the airplane out of the hanger Dec. 1 and fired up the engine. Ran well, no leaks, no parts flew off or from within

Best of luck,

Brian Walker
N1197E 7AC/DC

[Aerco]

Thanks for the replies, I will certainly try to do all the assembly work myself then, and get my A&P to look things over and make sure he has everything looked at and checked out and make sure he trusts my work. Which shouldn't be a problem. I feel far more comfortable with an engine that I personally assembled than to trust somebody else, no matter how good their reputation. I hardly ever owned any kind of vehicle that had any parts I did not disassemble at one point!

[Richard Murray]

Brian,

Can you provide more information on the Mattituck video? I have a couple of A-65s and have been trying to get up the courage. I have the blessing of a good A&P, have the Continental overhaul manual, and probably the same ebay video showing the process circa 1940.

Thanks

Richard

[Paul Agaliotis]

Peter,
The Feds don't consider the overhaul a major repair per FAR43 app.A, so just an A&P can do the work. Make sure you keep the records needed per FAR 43.2 and it gets recorded using FAR 43.7(b). For a little light reading look up AC43-9C(7). This has some added information on the maintenance record sign offs.
That little engine has about 8 moving parts so it will be no problem for you. Find a shop you trust and let them do your machine work and inspection, I use ECI. If I'm not installing new cylinders I use two builders up here in Norcal. The cylinders can be a little tricky and you need someone that has a bit of experience with them. It's the valve and guide work that causes the most problem for the re-builders.
Paul

[Champ Dreamer]

Peter,

I'm 90% sure this is the one http://www.actechbooks.com/products/act136/ I believe it is at my hangar. I'll check tomorrow, if that is not the correct one, I'll send you the correct info. Also, a parts manual is very helpful. Continental has several other pertinent publications, if you decide to proceed, let me know and I'll send you a list and some tips. As previously mentioned, if you change the air filter (to a different type), it is a major repair or alteration and requires a form 337. Performing a major overhaul to the engine to which the air filter is attached, however, is NOT considered a major repair or alteration, and noly requires a log book entry. I guess I'll never figure out the feds !

Brian Walker
N1197E '46 7AC/DC

[MikeB]

Paul,
Here's a question for you. The Chief project I'm looking at had the A65 case redone by ECI or DIVCO (unsure which one). According to the tag (1995) the case was surfaced and bores recut to size. Here's the question: among the paperwork I found an Aircraft Technology Corporation Service letter referring to a STC in cooperation with ECI to furnish engine bearings for the .020 crank. Accordingly these are the only bearings approved for installation in the engine. This apparently true for crankshafts that need to be ground .020 under for A65 thru 0200. Is this true for all cranks that need to be ground .020?
Not a problem as the bearing kit is coming with the engine but I'm just wondering. I also noticed that the thrust surface on the block has been redone and a new pin.

I took another look at this Chief project again today and it's starting to look more promising. All the internal engine parts have been reconditioned. Logs are there for the airframe. None for the engine but we can start a new one. I sliced the fabric back on the tubing. It's rusty under the fabric but I couldn't drive a punch through. It's definitely a 'basket case' but looks pretty complete and quite a few extra parts including four (?) doors. I did promise myself I wouldn't do this again but........

Thanks,
Mike

[Paul Agaliotis]

Mike,
The reason for the STC requirement is that Continental only supplies information for the undersize of the crankshaft by .010. If you decide to install any item or process NOT approved by the manufacturer, it requires some kind of approval. In this case a STC. All .020 Continental crankshafts require some kind of approval, not just by a STC, but could also be a major alteration via a 337 form. As part of the STC most cranks will be nitrided, which is a good procedure.
The A series used a flanged shell bearing up front for the thrust surface. If the case has an added pin for a separate thrust washer assembly the case may have been modified. It's not really a bad thing, you just need to order the correct bearing set.
Paul

[MikeB]

Thanks Paul,
That's what I kind of suspected regarding the crank undersize and bearings. The crank kit comes with all new correct bearings, including the thrust, so that's not a problem. I'm not excited about the pinned thrust bearings rather than a flanged type. I've seen the pins sheared on other engines and the two piece thrust fall into the crankcase. Maybe they're OK in this case since there's no clutch involved.

Mike

[Paul Agaliotis]

Mike,
The thrust pin in the small Continentals doesn't seem to wear too much. Most of the time it wears the bearing itself.
I know what you mean about the pins, I have a little experience getting them out of the main caps on the 8V71 Jimmys.
Paul

[MikeB]

The 8V71 was one of the engines I was thinking about as it seems they had a brass pin to secure the thrust bearings.

Mike