woodcrest

My 89 C4 was bought with a blown head gasket. I assumed due to overheating, but the owner claimed it never overheated and to be honest I took them as honest people. As for plugs, it had 7 of the Autolite 3936 and 1 BETU platin 828 (this plug had a Mercedes Benz symbol on it). I was told the wrong plug could have likely caused the blown head gasket, not necessarily always caused by overheating. If this is possibly true it is good news for me, I would rather the cause be an incorrect plug than overheating. Was it just by coincidence that the blown cylinder had the BETU plug, or was it likely the cause? Comments?

wadenelson

Having worked on cars most of my life I cannot think of any way that the incorrect plug could cause a failed head gasket. Not even badly misgapped.

Failed head gaskets --- overheating, clogged catalytic converter (too much back pressure), poor design (Subaru), etc.

vader86

Nope. Consistent overheating will, but this wouldn't be directly due to the plugs themselves.

billschroeder5842

Yeah, that is not going to happen. That would be a serious powerful plug to blast out the gasket.

Tom400CFI

If the plug were the wrong heat range, and cause detonation/preignition constantly....then it's possible that it could contribute to a blown head gasket.

But in reality, it's incredibly unlikely. Basically, no.

383vett

In a race application, if a plug that is too hot is used, it could definitely cause problems. Usually a broken piston or ring but possibly a head gasket.

Tom400CFI

I agree. At WOT it could cause issues. I was ASSuming "Joe Duff" 'Vette owner.

cv67

Blown HG on that cyl its common on them, doesnt need to overheat to get there either. Join the club