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Discussion Starter · #1 ·
Ok my lude has been running alittle rough lately so I decided to conduct a compression test.
My results were as follows:

Cylinder #1 #2 #3 #4
215 50 210 200


1,3,4 is extremely high in my opinion. I think I have a burnt valve because I also did a wet compression test (dump a tea-spoon of oil in cylinder) on #2 and the results did not change and also my spark plugs are pretty white.

Any comments,suggestions are appreciated.
 

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i wanna say the high numbers you talk about are near right and the "50" is really low... id replace that spark plug and see what happens
 

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Discussion Starter · #3 ·
i wanna say the high numbers you talk about are near right and the "50" is really low... id replace that spark plug and see what happens
Na man spark plugs are all takin out during this test.
Sorry I should of also mention that I have an H23.
 

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Discussion Starter · #5 ·
More likely a bad valve than rings if the wet test gave the same results.
I guess I have to get somebody to do a leak-down to pinpoint exactly what it is.
 

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Probably a good idea. There's a good chance that it's one of the exhaust valves since it's only in one of the cylinders btw.
 

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Discussion Starter · #7 ·
I guess those other numbers that I called ''extremely high'' were within spec I guess.
My bad. I just looked it up.
 

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yeah i knew the spec numbers and yours were good... i just dont know a lot about compression and how its all done... havent done research into that yet...
 

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Discussion Starter · #9 ·
yeah i knew the spec numbers and yours were good... i just dont know a lot about compression and how its all done... havent done research into that yet...
yea its cool man. Its real easy to do and takes like 15 minutes.
 

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I Miss My BB2 :'(
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holy shit dude 50? thats really low. i hope you find out what it is.
 

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Vrooom PSHHHH
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do a valve adjustment on cyl 3 and see if that fixes it
 

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Vrooom PSHHHH
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I think you mean Cylinder #2. :grin:
no, I mean doing a valve adjustment on 3 will fix the problem on 2

lol yeah, you're right, my bad haha
 

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The simple way to see where you are leaking is (if you have an air compressor);

Bring #2 up to TDC (in gear to hold there), remove the oil filler cap and radiator cap, pump air into the cyl. Look into the radiator, listen at intake, exhaust, and the oil filler.
This process wil locate which area is leaking before tearing it down.
If the air comes out the intake or exhaust, check the valve lash there before pulling the head.
Good luck.
 

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Discussion Starter · #15 ·
Ok I guess Im going to adjust cylinder #2 in attempt to solve this problem because itll cost me nothing and its worth a try.
Hopefully it works,but Im not getting my hopes up at all.
 

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yes, you always have to have a properly adjusted valve lash to do a compression test. so do that first and re-test it and see what happens.
rockers set too tight will cause low compression test results. rockers set too loose will cause high compression test results. so adjust all 16 valves to spec, its the only way to get an accurate reading, and its the only way to have a properly running engine

if you still have one cyl that is drastically low, i would bet on it being a leaky valve. leaky rings and/or damaged pistons only cause a minor drop in pressure, not one as major as that.
 
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