[s-cars] ///S4cylinder-Lehmann eng. disassembly

[AUDIJIM at aol.com]

Since I spun #5 con rod bearing on my 2000 mile engine, I needed my spare  
engine's crank. This engine if you remember was the one running on 4 cylinders  
soon after start up. It is a documented Lehmann engine installed by John 
Buffum  at Libra Racing. I pulled the head and set it a side. The pistons all look 
good  with the exception of #4. They are different pistons for lower 
compression. I'll  take pictures of them soon. All the rings look good with a little 
bit of carbon  on them, and the cylinder walls look great (all 5) I was 
concentrating on #4  piston because I thought that was the problem. The head gasket 
looked good as  well. I thought for sure that I had a broken compression ring or 
a burned piston  or a possible head gasket problem. I couldn't see anything 
wrong until I flipped  the cylinder head over. It looks like something was 
bouncing around between the  cylinder head and the piston face. Even thought I 
drove the car this way from  the previous owner, I can't help but think that 
maybe a spark plug lost it's  center electrode and started creating havoc  in #4. 
I haven't disassembled  the head as yet, but it's either a burned valve, a 
bent valve or a combination.  I think it would start in 5 cylinders and drop #4 
because of a little oil  sealing the combustion chamber and then getting burned 
off or blown out. Just  because the rings looked OK does not mean that they 
are. I'm sure this engine  had a combination of faults. If you recall that my 
leak down test on this engine  was horrible. The compression test was low, but 
I contributed that to the lower  compression pistons.
 
More to follow.....
 
Jim