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Old 11-04-2012, 03:21 PM
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downhiller downhiller is offline
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Originally Posted by 7pilot View Post
With certain types of bad Head gaskets, the coolant temps stay normal when the car is operating in the street, and even when driven enthusiastically on the street.
However, when the engine is exposed to sustained high loads and RPMs, the cylinder nearest the weak spot in the gasket pumps air through the bad spot and into the coolant circuit, causing coolant temps to spike. When the engine cools off, the coolant may leak into the cylinder.

The coolant system should be pressure checked, and a leak down test performed on the cylinders.
Until these items are judged healthy, any work on the cooling system may be a band aid until the engine is again in a sustained high load state.

a bad hg is a bad hg. the only difference between a normally operated engine verses the same one being raced, is its at higher rpms more often. however, its still within the manufacture specs on combustion pressure. so if a hg is leaking while racing, its gunna leak driving around on the streets as soon as it gets to op temp.

theres 2 main ways a hg can fail, which either leaks all the time, or only leaks when the cooling system gets to pressure. not if your driving down the street vs racing.
I know a lot about cars. I can look at a car's headlights and tell you exactly which way it's coming
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