National Aeronca Association Bulletin Board

Had a chance to work on my L3B recently and pulled apart the original 1942 engine which has been sitting in a shed since 1952. It appears it had 156 hours on it. I didn't know what state the insides would be in, but after dismantling (it all came apart without any problems), cleaning and checking dimensions, it turns out every single part of this engine would have been usable as is. Even the neoprene needle in the carb looks fine. I will be replacing things as a matter of course, but I was pretty pleased to say the least. I'll hone the cylinders, fit new rings, lap the valves. No point in doing a major overhaul with these hours and in this condition, so it will be Inspect and Repair As Necessary.

I'll probably bit the bullet and pay for a steel needle for the carb - somebody needs to make these cheap! With today's CNC stuff it ought to be joke.

The Bendix mags also seemed fine - fitted new bearings and condensers and gave them a general overhaul; judging by the way they zapped me while turning them by hand, they seem to work. Will throw them on a testing machine soon.

The exhaust was rusted a bit thin here and there, but I patched it for now, it ought to last a while. When the time comes for a replacement, that could be a tricky job.

My spare core engine wasn't in quite so good condition; I managed to get two cylinders off (with the pistons at BDC), but so far the other two are stuck solid. It's a fairly low hour engine too and the cylinders seem ok, as does the crank, but the cam and lifters are rusted up. Tried every trick in the book short of filling up the cylinders with gunpowder, fitting a spark plug, hooking up a mag and seeing if it blows off. (Don't do this at home...). Anybody have a magic formula for dealing with this problem? Believe me,I tried all the obvious ones.


Would like to post some pictures, but it keeps saying "The board quota limit has been reached".

Peter,
I've used coca-cola to loosen up stuck engines. Had to remove a stuck piston in a a pretty rare engine and made an adapter to fit in the spark plug hole that was tapped for a grease fitting. It took a lot of grease but it pushed the cylinder off with no damage.
Paul

Paul,
That's kind of interesting as I remember using Coca-Cola to loosen up the pistons on some kind of an engine (think it was an Oliver diesel) left on top of a mountain with the exhaust uncovered when I was in Alaska. Although it took some kind of extra effort with a two by four and hammer to work things loose too. Never thought about the grease fitting trick but that should work too. We used to force pilot bushings out by filling the void with grease and driving a steel rod in.

Mike

You can try a product called Evaporust too. Some have good luck using that. You can find it at the aviation counter at Tractor Supply.

Got one cylinder at a time soaking in a bucket full of mineral spirits. Let's see what that does.

I even tried using a regular car engine hoist; I tied a rope through the rocker arm bushings and hung the engine from one cylinder. Did the same on the other side and secured it to the lower legs of the hoist and cranked away. All that happened was the ropes snapped eventually after a fearsome amount of tension. It is STUCK, but I'm not giving up. I'm one of those people who can't bear to throw away a potentially useful piece of metal.