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Is there a trouble shooting guide for diagnosis HG, etc..


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Just wanted to know if anyone had a trouble shooting guide out there......certain symptoms would be this or that...?

 

It is now starting to get hot out there and the probs are going to startup....

 

Bryan:rolleyes:

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One thing I haven't seen mentioned much here is a hydrocarbon test on the radiator. I "sniffs" gases in the radiator while the engine is running; if hydrocarbons show up, it's proof that combustion gases are getting into the coolant system. Ergo, leaking head gasket.

 

From what I read, it's virtually foolproof. Sure, you can have bubbles in the coolant, or coolant in the oil, but unless these are REALLY obvious, you usually second-guess whether what you're seeing is what you're dreading. For this reason, I got a hydrocarbon test kit when I suspected a leaking HG. The test detects even minute levels that show up long before any other signs.

 

Turns out I didn't have a leaky HG, so I don't have that much experience with diagnosing them.... But from what I figure, since combustion pressure is so much more than coolant pressure, a leaky HG would surely cross into the coolant on the piston upstroke. (On the downstroke, it would suck in some coolant, which shows up as oil contamination. I suppose it's remotely possible for a flaky HG to act as a "check valve" for a while and allow a one-way leak. Seems I've even read about that here.)

 

The condition that a hydrocarbon test couldn't detect is a leaky HG between cylinders. This isn't so uncommon. Compression test would show this.

 

I picked up a hydrocarbon test kit for $25 online at some tool store. I think Napa also carries it. Or a shop should do a one-time test for about the same amount.

 

-- Mark

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