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Hello every1
I have mercedes 1993 320E
I want to check if I have a blown head gasket
anyone know how to check blown head gasket without chemical tester or emission gas tester cus I don't have any of these
I saw a video for Paul Danner explaining how to check it by relative compression but I don't remember what was the subject
anyone can assist me please
Thank you soo much
I watched this video and it was useful for me
But I still interested to know how to determine a blown head gasket by relative compression waveform ...
No problem. The only way I can think of would be to know the firing order and watch for two peaks to be off next to each other since the two cylinders could both be losing compression. I'm not sure if this is a 100% determining test though. I wouldn't count soley on those results but maybe I'm missing something.
There is no real catch all test for a blown head gasket, head gaskets can fail in different ways. For a relative compression test or any kind of compression test to show a bad gasket it would have to be a major failure. Of the tests available the most likely to give a reliable result is gas testing the coolant tank but that only works where cylinder gas is leaking into the coolant. A lot of the cylinder head gasket failures I have seen on modern "open deck" engines are coolant leaking in to the oil side or oil leaking into the coolant. Leaks between adjacent cylinders are rare although some old style closed deck engines with "siamesed" bores did suffer from it the old Austin/MG A series 4 cylinder was known for it between cylinders 2 & 3. Calling a head gasket failure boils down to experience, if there is mysterious water loss then I would always do a cold pressure test for coolant leaks first.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
If I suspect a blown head gasket, I use a relative compression test as a guide. If the relative compression test shows me a low cylinder, I then to a compression test with a gauge. You can also perform a cylinder leak down test if you need to distinguish if its valve, rings or gasket. I agree with Andy, if I have low water, I do a pressure test of the coolant system. If I can't find an external water leak fairly quickly, I look really close at the head gasket.
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