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Old 03-02-2014, 05:27 PM   #1
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Default 3800 compressions?

My lovely engine again.


I do compression test and every other cylinders give 160-170psi but 1,3 (adjacent cylinders) give 140psi both.


Car gives white smoke/ steam on warm engine. Nothing brutal but still.

Haynes manual says 30% different highest lowest is okay. That result is ok then.

Another says 20% and then we are pretty close...


It wont drink coolant and oil/coolant arent mixed.
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Old 03-02-2014, 08:21 PM   #2
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sounds like a problem is starting though. if you remove the plugs and put a little oil in the hole you can narrow it down. if its the same your problem is head gasket or valve related, if it goes up its lower like rings or worn cylinders
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Old 03-03-2014, 11:39 AM   #3
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So you think there is something work?



I asked local "guru" and he said that 140psi compression are very good. He didint say anything about 170 -> 140 difference.


Usually bad headgasket/rings will drop compression about half of normal?
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Old 03-03-2014, 03:22 PM   #4
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depends how bad it is. if the leak is not that bad then it will still have most of the compression
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Old 03-03-2014, 03:41 PM   #5
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Can it be nothing else than head issue or piston rings? Just more wear?


But if its gasket and results are that, then i have to wait that gasket will go more bad and clear issues come or gasket job now.


**** that ****.


Nobody ever checked compressions to this engine?

Very scanty issue on internet. Just normal wear results or compression totally down.


Intake manifold gasket wont affect there?
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Old 03-03-2014, 04:08 PM   #6
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Did you do a dry test and then a wet test? You have to have all the plugs out and a well charged battery to do both tests.
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Old 03-03-2014, 04:16 PM   #7
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Do you mean wet test -> oil in cylinder?


Engine was warm, all plugs out and battery was good.

I did test two times. Last time i cranked all cylinders about 7-8 times.

First time about 2-3 times nad all give same 140 etc but when i tested one cylinder, i confused for starter crank time and then i did test again with more cranks for sure result.
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Old 03-03-2014, 04:25 PM   #8
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Yes. Wet test, a spoonful of oil in each cylinder.
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Old 03-03-2014, 04:45 PM   #9
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Have to try that.

If oil helps, i dont think there is nothing to worry then because compression is still okay.


Head gasket gives at least 350 costs damn.
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Old 03-03-2014, 04:54 PM   #10
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head gaskets are relatively cheap here as long as the head is not warped. machining the head is pretty costly
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