Just got back 2 weeks from holidays, we thought possibly the worst, with all the clattering, that perhaps we had a spun bearing etc.
Anyway got off the phone with our engine guy, the noise was coming from a rocker that "jumped off" which he said was caused by overrevving. The other major issue was that both head gaskets were blown, and oil was incredibly sludgy. He told me, normally he might not disassemble the bottom end except that the sludge was unbelievable.

Anyway, so my 1st question, is it possible that the poor oil condition contributed to the rocker "jump" from the pedastle, or is he right simply over revving (In which case it might have been at the shop where the clutch was just replaced, as my son said the engine was clattering, when he picked it up until they added oil)

2nd question, what are the very best head gaskets available fro felpro or whoever, for this engine?

thx

So the rest of the engine, looks very good, with very little wear. Looking at re-ring, new bearings, gaskets etc. Stock cam probably cause if the rocker system is a weak link, I wouldn't change a cam without addressing the whole valvetrain.

 

Felpro gaskets! MLS. Over revving can cause this problem. Don't forget that the pushrods act like springs at high RPMs and could cause more play between the pushrods and the rocker arms. GM makes a chromeloly pushrod , its lighter and can withstand the flexing at high engine speeds. Look in the GM highperformance parts catalog. 5/16" diameter is enough. Remember that engines with roller cams have a different length push rod than non-roller engines. The sludge problem is serious, ask anyone with the Buick V6 and had Dexcool in the radiator.The sluge can block the inlet screen on the oil pump and this will lead to reduced oil pressure which will effect the "pump-up" ofthe lifter. I hope this info helps. 93ZTed.