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.
Erik