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HELP! Compression and leakdown results, possible blown headgasket?

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Old 06-18-2006, 04:29 PM
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Exclamation HELP! Compression and leakdown results, possible blown headgasket?

The car started idling bad, had pressure at the oil cap.
Was smoking constantly white/blue smoke very heavy.

I pulled the plugs and #5 is wet and covered in oil.

Compression test - 5 cylinder was about 30-45 psi, #7 was at 90psi all others were at 160psi (cold)

Leakdown - I'm getting 0% on #5

Coolant in Rad seems to be low, car was never overheated.

What's my next step, pull off the head to check the headgasket? Can you actually see on the gasket when it's blown?

Any other suggestions as to check before I remove the head?
Old 06-18-2006, 04:36 PM
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You can check to see if there is oil in the coolant, but Im pretty sure you blew the hg between 5 and 7.
Old 06-18-2006, 05:15 PM
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I pulled the dipstick couldn't really tell. I just changed the oil, but I guess I could drain it again...
Old 06-18-2006, 05:17 PM
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Gotta pull the head, you'll find out then. Pressure in the oil cap doesnt sound promising however....
Old 06-18-2006, 05:42 PM
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put oil in cylinder #5, see if your compression jumps right up or not.
its called a wet compression test to detect worn rings
Old 06-18-2006, 06:34 PM
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should I pull the head, will I be able to see if it's the head gasket once I pull the head and look at the gasket? Or are the holes so small I won't be able to see with the naked eye?
Old 06-18-2006, 06:45 PM
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You should be able to see it. The gasket will be deformed where its blown.
Old 06-18-2006, 06:51 PM
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excellent, I'll pull it, I suppose I can't cheat by not draining the coolant because it will just go everywhere right?

So I have to drain the rad and engine block before I pull it then? Or can I just stick a towel over it once I pull the head?
Old 06-18-2006, 07:21 PM
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Drain it. Search for a post about draining it using a vacuum as well.
Old 06-18-2006, 07:24 PM
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Drain it. Even drained you'll still get some coolant splashing around. It will get into the bolt holes so make sure you dry the holes out with a paper towel or compressed air before you reinstall the head. My guess is that you will find head, piston, or ring damage if you have alot of oil in the cylinder and pressure at the cap.
Old 06-18-2006, 07:25 PM
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Originally Posted by Viper
Search for a post about draining it using a vacuum as well.
This works VERY well.




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