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Quattrocket
12-02-2005, 10:47 PM
just did a compression check on the car. Did one a couple weeks ago and they were all 180 psi all four cyl. now 1,2,3 read 180 and 4 reads 170. they all stay strong and dont lose compression over time. anything to be concerned with?

Crisqo
12-03-2005, 07:36 AM
where'd u get a compression test done?

Quattrocket
12-03-2005, 09:07 AM
I have a guage

Neo1130
12-03-2005, 09:41 AM
How many times did you test it... I am willing to bet your battery was starting to drain down a bit...

offroader1006
12-03-2005, 10:59 AM
that acceptable, usually anything under 15% difference is ok.

Quattrocket
12-03-2005, 12:42 PM
I just tested the 4 cylenders once

offroader1006
12-03-2005, 12:44 PM
you mean one revolution?

Neo1130
12-03-2005, 02:02 PM
Originally posted by offroader1006
you mean one revolution?

If he did it for one revolution then the reading wouldn't even be that close...

170 is within range but like I said, it could be the battery was just drained a bit more on that test than the others... Either way, you are still good...

offroader1006
12-03-2005, 06:20 PM
thats what i was trying to get at. i test at 4 revs.

if your concerened you can always do a leak down test to make sure its holding pressure as well as the others.

bitterchild
12-03-2005, 08:50 PM
what neo is saying is as you test 1-4 in order, the battery voltage after testing 1-3 is lower than when it started. hence a slower crank and lower pressure reading. That's why you throw on a battery charger when doing compression test and allow the battery to recover. That's also part of the reason for the allowance between readings. 170/180 is perfectly fine. Seems like you're overdoing the compression tests... i see you post one every week :p

Quattrocket
12-03-2005, 09:49 PM
Yeah i understand now. i went 6 revolutions each cyl. thanks guys.

offroader1006
12-04-2005, 11:03 AM
Originally posted by bitterchild
Seems like you're overdoing the compression tests... i see you post one every week :p

nothing wrong with that, jsut likes to make sure hes in good shape. probably gets a prostate check once a week too[:D]

Quattrocket
12-04-2005, 01:21 PM
Originally posted by bitterchild
what neo is saying is as you test 1-4 in order, the battery voltage after testing 1-3 is lower than when it started. hence a slower crank and lower pressure reading. That's why you throw on a battery charger when doing compression test and allow the battery to recover. That's also part of the reason for the allowance between readings. 170/180 is perfectly fine. Seems like you're overdoing the compression tests... i see you post one every week :p
lol, yeah m just really concerned lately, I did one last week, and at the end of this weekthe car started to run like crap again. so i pulled the plugs and they were fouled yet again. so I checked for compression just to be sure the was no oil leaking.