Fixing poor leakdown, Cyl 1 leaks at 50%, rest are cool. |
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Fixing poor leakdown, Cyl 1 leaks at 50%, rest are cool. |
VaccaRabite |
Oct 24 2007, 07:00 AM
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#1
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En Garde! Group: Admin Posts: 13,554 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
So, at the Sterling meet I did a leakdown test on my motor, and found a problem with Cylinder 1. 45% leakdown, but 120 lbs of compression. Was tempted just to let sleeping dogs lie, but pulled the head off.
What was going on was clear as soon as we did that, the head was not totaly sealed to the cylinder, off by a very small amount. Instead of having the head recut, I decided to try and lap the two of them together. So, last night I hand lapped them, using ground graphite to check for even contact. I got good contact after the third round of hand lapping (lap, clean, check). Now I need to get the jug back on the block. I have a ring compressor on the piston, but I can't ficgure out how to get the head back on. Do I have to take the piston head off the rod? If so, how do I get it off. It looks like that tis a spring keeper that needs to be removed. Is there anyhting on the rod the needs to be loosened before I can pull the pin out to remove the piston head? Obviously, if there is a trick to getting the jug back on without pulling off the piston head, I'd like to do that. Zach |
VaccaRabite |
Jan 3 2008, 03:37 PM
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#2
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En Garde! Group: Admin Posts: 13,554 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
I just dropped Cyl 1&2 and piston 1 off at Air Cooled Racing. I could not get ahold of the local guy at Bug World - he is really part time these days.
Anyhow, Steve at Air Cooled was very cool, and we ended up talking for about an hour as he showed me all the stuff he was working on at his shop. If you happen to be in the big GT-headlight group buy, I saw the kits. VERY nice! So, the cylinder should be punched out in 2 weeks or so. I asked him to bore out the new cylinder, check the rings on the piston to be sure they were still good to use, make sure the new cylinder was squared on both mating surfaces, and cut the "new" cylinder to the same height as the #2 cylinder. There are several VERY NICE 914s at Air Cooled. He is already getting his stuff ready for the Hershey meet in April. Zach |
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