626 is getting an overhaul

[Tim]

Hey all, 626 hasn’t flown in a couple years because the engine is just clapped beyond clapped. It was never quite right in all the time I’ve been around it, leading to the airplane’s grounding, which brings us to yesterday when I started prepping to pull the engine.

Anyways I’m starting this thread to long what I’m doing, what’s been done by those before me, and to ask any questions that come up (there will be a bunch). While I’ve never opened up a Model A before I’ve done two T’s so I do have some small skill base to build on.

[Richard Roller]

Good to see your post. I'm in the process of rebuilding 34KP (model A powered) after putting it on its back 2 summers ago. I've rebuilt the A a couple of times over the last 20 years. Happy to help if I an be of help.

[Tim]

Thanks for the offer and I’ll definitely be looking for all sorts of info on clearances, etc. when I get to it. I expect they’ll be different in an airplane than they would be in a car. No doubt I’ll be looking for other advice too.

For now though, is there anything non-obvious about taking an A engine apart? Common newbie mistakes, etc?

[Tim]

I gave myself an education today in how not to remove a Model A engine. Nothing broke, it was just more work than it needed to be.

Looking back, I should have pulled the wood engine rails and their steel braces off along with the engine. It doesn’t seem obvious at first glance though so let it be a caution to anyone else removing an A from a Piet they didn’t build.

Anyways, it’s off and ready for teardown.

[Tim]

I’m not great at reading plugs, what’s this one trying to tell me? Lol

Other than that, the engine so far has been about what I was expecting. The head gasket shows signs of being blown in two places, most of the valves are sticking, there’s rust but so far nothing critical.

So far I just have the head and all the ancillary bits off. I think I’ll clean up and refinish what’s been removed before taking anything else off the block. Any recommendations on paint for the intake manifold, water pump bushing carrier, pulleys, etc?

[Tim]

Looking ahead a bunch, what are the other Model A flyers using for torques, clearences, etc. when building up an engine? I don’t mind being directed to a specific book on Model A rebuilding but are there any aircraft-specific differences?

[geresh]

I don't have any knowledge of putting a 'A' engine together, but I am interested in how your build progresses. I recently painted some certified engine parts using an Eastwood 2K paint, and wow, is that stuff serious! Seems to be a tough product.

[taildrags]

This may sound sacrilegious, but how about using standard-issue industrial equipment paint for the engine? Rust-O-Leum and others offer such paint and I believe Ford blue is used quite often on tractors.

Oscar Zuniga
Medford, OR