Did I blow my headgasket?
#31
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Originally Posted by Keithr726
Geneqco you are the man! I'm having a problem where there is brown crap on the walls of my coolant tank but not in the liquid itself and every month or so my coolant level drops and inch.
What about using PH paper to check acidity in the coolant?
What about using PH paper to check acidity in the coolant?
#32
Nordschleife Master
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I used the ph paper today and the coolant turned it a dark greenish blue (basic). I tried a drop of oil on a new piece and the paper just absorbed the oil so I have no idea for that.
What is a leak down test?
I looked at two coolant pressure check systems and they were $75-100 ouch. I'll have my shop do it when I decide between leak down and compression check.
What is a leak down test?
I looked at two coolant pressure check systems and they were $75-100 ouch. I'll have my shop do it when I decide between leak down and compression check.
#33
Instructor
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You can get a coolant exhaust gas tester at most auto parts stores. But it very difficult to get a reading in this type of failure because once the cooling system is pressurized from the cylinder gasses, you can't readily pop the reservoir cap and hold the tester in place to get a reading.
Although water will leak out of bad fittings under pressure, this doesn't necessarily mean that air (at atmospheric pressure) will "leak" in.
Pressurizing the coolant system? Soot in the coolant reservoir? Sounds like a head gasket to me. Try this:
Fill the coolant system to half way between low and high marks. Thoroughly bleed it. Run the coolant overflow pipe at the neck of the reservoir into a catch bottle. A plastic soda bottle tie-wrapped somewhere will do. Then go out for a "spirited" drive. Get the engine up to temp and repeated get on boost as much as you can. Coolant will get into the catch bottle if the system pressure exceeds the cap's rating. Got any coolant in the bottle? If so, you're pressuring the system from a failing head gasket. Slim possibility is a weak coolant cap - did you check its holding pressure?
BTDT
Good luck
Jon.
'86/89 951
Although water will leak out of bad fittings under pressure, this doesn't necessarily mean that air (at atmospheric pressure) will "leak" in.
Pressurizing the coolant system? Soot in the coolant reservoir? Sounds like a head gasket to me. Try this:
Fill the coolant system to half way between low and high marks. Thoroughly bleed it. Run the coolant overflow pipe at the neck of the reservoir into a catch bottle. A plastic soda bottle tie-wrapped somewhere will do. Then go out for a "spirited" drive. Get the engine up to temp and repeated get on boost as much as you can. Coolant will get into the catch bottle if the system pressure exceeds the cap's rating. Got any coolant in the bottle? If so, you're pressuring the system from a failing head gasket. Slim possibility is a weak coolant cap - did you check its holding pressure?
BTDT
Good luck
Jon.
'86/89 951
#34
Nordschleife Master
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I just replaced it a month ago after seeing how destroyed the seal was. Since then the coolant level has dropped a half inch. I filled it up today to see what happens. I'm planning on a compression and leak down check next weekend.
#35
Rennlist Member
Thread Starter
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Originally Posted by Jon Schepps
Slim possibility is a weak coolant cap - did you check its holding pressure?
BTDT
Good luck
Jon.
'86/89 951
BTDT
Good luck
Jon.
'86/89 951
What pressure cap should I get as a replacement? Do local auto supply stores carry them, or do I need to order from one of our sponsors? The only number on the cap is "150", it's a Behr brand.
#41
Rennlist Member
Thread Starter
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Originally Posted by TRP951
I went to my local auto store and got a cap that fit with 16psi and it works fine for me. Though the stock 150 cap is kPa so that is like 15psi
I did find a nice 17mm hex head socket to remove the transmission drain and fill plugs though!
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#44
Rennlist Member
Thread Starter
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Does this make sense?
A friend of mine said to put the coolant pressure tester on the reservoir. Start the car up from cold. If the pressure tester gauge immediately begins to rise, the headgasket is bad. The key word here is 'immediately' because as the engine/coolant heats the pressure will rise. So basically you are looking for an immediate rise in pressure.
Does this sound like a reasonable diagnostic method in addition to all the others already stated?
A friend of mine said to put the coolant pressure tester on the reservoir. Start the car up from cold. If the pressure tester gauge immediately begins to rise, the headgasket is bad. The key word here is 'immediately' because as the engine/coolant heats the pressure will rise. So basically you are looking for an immediate rise in pressure.
Does this sound like a reasonable diagnostic method in addition to all the others already stated?
#45
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Originally Posted by shiners780
Just got back from Auto Zone, their computer stated 16 psi was the replacement part. The spring seemed much easier to press than the one that was on the car, very noticeably easier. I was reluctant to buy it, but sounds like yours works just fine.