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Re: 1988 8-valve head gasket diagnosis request Posted by Justin VanAbrahams [Email]  (#32) [Profile/Gallery]
(more from Justin VanAbrahams) on Tue, 22 Aug 2017 12:27:41
In Reply to: 1988 8-valve head gasket diagnosis request, Marko, Tue, 22 Aug 2017 12:04:51 Members do not see ads below this line. - Help Keep This Site Online - Signup |
There are many ways in which a head gasket can fail, and not all of them are detectable in the same way. Using test strips into the coolant reservoir to test for exhaust gasses is one way, checking for coolant in the combustion chambers is another, performing a compression test is another, performing a leakdown test is yet a fourth. Head gaskets can fail between cylinders, between a cylinder and the outside world, or between cooling passages and combustion chambers. They can fail in a minor way or in an obvious or catastrophic way. There really isn't a single, for-sure test that always works.
Based on your symptoms, it seems that maybe the head gasket has failed between the combustion chamber and a coolant passages, you could probably use a variety of these methods to test - remove the plugs and physically look inside to see if coolant is pooling on a piston or see if one or more pistons are abnormally clean by being "washed" with coolant. Use an exhaust gas test on the coolant to see if any is present. Use a leak down tester to see if pressurizing a cylinder results in air escaping into the cooling system. Use a cooling system pressure tester to see if coolant is being forced into the combustion chamber (remove the plugs first ;).
However, you could have other issues as well - a clogged radiator, a bad water pump, a leak in the cooling system that is sucking in air when it cools, a cracked head or cracked block.
IMHO, the two most productive tests will be a leak down test and a cooling system pressure test. The easiest will probably be a physical inspection of combustion chambers to see what they look like... they may give you a clue about the nature of the problem.
posted by 12.195.130...
, Fri, 1 Sep 2017 19:07:03, Tue, 22 Aug 2017 12:27:41 <-- Viewing This Message
, Tue, 22 Aug 2017 20:16:25
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