> 
> > My Uncle bought a 76 westy that just had a new top end job.  It ran great 
> > for a few thousand miles and then the valves began to tighten.  They 
> > would retighten a couple of hundred miles after adjustment.  The engine 
> > finally gave up when #3 piston exploded.  He is rebuilding the engine now, 
> > and the shop that checked the heads said they showed signs of over heating.
> > Does anyone have/had the same problem, or know what the cause might have 
> > been?  The engine was not neglected oil wise.
> 
> 

 I'd speculate that perhaps a valve broke and the loose piece caused the 
 piston to break up. This has happened to me on my old '64. The fact that
 the valve clearances were tightening up rapidly may have been an indication
 that the valve stem was stretching. It can also be caused by valve seat
 recession <seats too soft> but I think that occurs more slowly.

 One should probably be suspicious of the buying a vehicle that has "just been
 rebuilt". If the previous owner has decided to sell _before_ doing the rebuild
 chances are they will go for cheapest everything and I think we all know that
 there are a lot of inexpensive, poor quality, unreliable aftermarket parts
 available for VWs.

 As to potential causes for overheating: check the cooling system flaps to make
 sure they open and close properly and make sure that the previous rebuilder 
 didn't leave out the tin directly under the cylinders. Ensure that the engine
 is tuned to factory specs, especially the igition timing.

 Dave