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Guys,
We are about to rotate the engine 180 degrees on the stand to put on the right side pistons and cylinders. I am thinking of chucking on a head, no gaskets, and putting a couple of nuts on finger tight to keep the cylinders seated in the case. Any pitfalls or better ways?

Bryan Cotton wrote:Guys,
We are about to rotate the engine 180 degrees on the stand to put on the right side pistons and cylinders. I am thinking of chucking on a head, no gaskets, and putting a couple of nuts on finger tight to keep the cylinders seated in the case. Any pitfalls or better ways?

I installed the cylinders in about five minutes with the engine horizontal on my workbench. If you ever remove the cylinders when its installed on the airplane, you'll be doing it the same way. That being said, I see no reason not to do it the way you describe other than being an extra step.

I assume your concern is keeping the cylinders seated to avoid future leaks at the bases of the cylinders? I have heard of that happening on this forum once, but my cylinders have been on and off and I've never re-applied the sealant since it was first assembled and I've never noticed a leak there--I think you should be fine. I don't really understand how a leak appears in this low pressure unsubmerged area.

I recommend watching Joe Norris's Aerovee assembly DVD if you haven't already. Watching his technique was very valuable to me.

I always build the engine horizontally. In fact, I just do it on a bench top. No stand or fixture required. No worries!

Thanks guys - next question. How do you expand the pushrod tubes, or are they already expanded?

Bryan,

If they've never been installed before, they should be good to go. If you've had the heads installed and have removed them, simply take the pushrod tube in your hand and gently pull on the "bellows" end while slightly bending the tube back and forth. You sort of stretch one side out at a time. Use a rag in the hand that's around the "bellows" end, as the end of the tube can be sharp.

Bryan Cotton wrote:Thanks guys - next question. How do you expand the pushrod tubes, or are they already expanded?

The pushrod tubes, where they enter the case and/or the heads, can be a source of oil leaks. Be VERY careful to make sure the seals are fully and squarely seated. I have found the super tin sometimes interferes with the pushrod tubes and they get shifted slightly. At the heads you can shine a flashlight behind and see if you can see any light around the rim of the pushrod tube.

Thanks guys - next question. How do you expand the pushrod tubes, or are they already expanded?

I used a socket that just fit inside the end of the tube and an extension to bend them back and forth a couple of times. That expanded the bellows and kept the ends from defoming.

Don't know about the 2180, but the stock VW engine has a published dimention from outside to outside of the bellows. They need to be re-expanded to that size if they are to be reused. I can get that for you, but it is a worthless value due to the stroke differance. I'm surprised the dimention isn't in the assembly manual.

Area 51% wrote:Don't know about the 2180, but the stock VW engine has a published dimention from outside to outside of the bellows. They need to be re-expanded to that size if they are to be reused. I can get that for you, but it is a worthless value due to the stroke differance. I'm surprised the dimention isn't in the assembly manual.

A published dimension has no meaning. The actual length depends on the barrel shims used, head gasket thicknesses, and some other variables. As long as the bellows are extended so that they have to be compressed when the head goes on and gets torqued down, that's what matters. Of course you CAN over do it. If you hyper extend the bellows, then when you torque the heads you are torquing against the pressure of the bellows. So just use some common sense.

Guess-timation is fine as long as one has some background or experience with a component in question. It is evident I wasn't clear enough in my statement that the published dimention was for a "STOCK" engine, and that it would be a "WORTHLESS VALUE" on a stroked engine such as the AeroVee. "I" wouldn't install the tubes without a given dimention, especially if it was my first build, any more than I would adjust the valves by "feel".


I'm still surprised there isn't a dimention to cover each possible incarnation of said AeroVee.