DDP

Can this happen? I'm pretty sure that it can, but I want to be sure. Thats all, thanks.

mark944turbo

No, a blown headgasket can not cause high oil pressure. High coolant pressure, yes.

M758

Well high crank case pressure can be caused by bad rings as combustion pressure gets past the rings and into the crankcase.

A failed HG will impact the cooling system as the HG seperates the combustion chamber from the waterjackets around the cylinders.

On the flip side you can have normal oil pressure with a failed headgasket.

DDP

Even if a compression ring is broken and it opens to the oil passage, it will not increase the oil pressure? Mmm.

mark944turbo

A compression ring is not a headgasket, and if it breaks it opens to the oil sump not an oil passage. High oil pressure is most likely an oil pressure relief valve problem, probably a mis aligned housing. What work has been done on the car recently?

DDP

No I mean the compression ring on the HG or the main ring that keeps the compression in the cylinders, not sure what you would call it. I will check the oil pressure relief valve.

Tom M'Guinn

The cylinders stand freely in their coolant jackets, so if there is a leak anywhere between the top of the cylinder and the head, the combustion leaks into the coolang jacket area.

Kevin Baker

Check your oil cooler (on the block). I had enough oil pressure to blow the gaskets off the bottom of two different filters. Turns out the oil and coolant were mixing in the cooler, causing a nasty jelly that clogged the filter and the cooler. Replaced the cooler seals, couple of oil changes, all good so far.

Jakerx

kevin, 951 oil coolers are not on the block. they're separate and have oil lines feeding them.

M758

Ture, But they still have two o-rings that can leak oil in to the coolant system. These o-rings are in same place the standard NA oil cooler is.