compression test, all low, burning oil
Thread Starter
Racer
Joined: Jul 2003
Posts: 401
Likes: 0
From: texas,, at last
compression test, all low, burning oil
guys,
i seem to be burning quite a bit of oil,
did a compression test and they range from 130 to 140,
now i know that if they are within 10% of each other it's supposed to be ok,
but,,,,everyone else seems to be getting in the 180's,
could it be all the rings are shot or does this now point to valve seals,
thanks,
neil
i seem to be burning quite a bit of oil,
did a compression test and they range from 130 to 140,
now i know that if they are within 10% of each other it's supposed to be ok,
but,,,,everyone else seems to be getting in the 180's,
could it be all the rings are shot or does this now point to valve seals,
thanks,
neil
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Re: compression test, all low, burning oil (camaroneil)
hi,
i put some oil in one cylinder and it went up from 140 to 155,
so does this mean rings,,,,,,,,
thanks,
neil
i put some oil in one cylinder and it went up from 140 to 155,
so does this mean rings,,,,,,,,
thanks,
neil
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Re: compression test, all low, burning oil (camaroneil)
Sorry to read the bad news neil. And I thought you had posted changing either cams or swapping engines recently this year? At least its still drivable until your ready to repair or replace. 
And there's no cheaper V8 to repair or replace than a sb Chevy. 
Thread Starter
Racer
Joined: Jul 2003
Posts: 401
Likes: 0
From: texas,, at last
Re: compression test, all low, burning oil (cardo0)
cardo,
this is the engine i replaced a month ago,
thought it was a good one, i got it off of ebay as a reconditioned engine,
looks like i need to stick new cam and lifters in my old engine and put it back in, all that was wrong with the original one was that it had a ticky lifter,
looks like i need to do some research and see what cam will be best,
i'm thinking a comp cams xe 268,,,what do you think??????
thanks,
neil
this is the engine i replaced a month ago,
thought it was a good one, i got it off of ebay as a reconditioned engine,
looks like i need to stick new cam and lifters in my old engine and put it back in, all that was wrong with the original one was that it had a ticky lifter,
looks like i need to do some research and see what cam will be best,
i'm thinking a comp cams xe 268,,,what do you think??????
thanks,
neil
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Re: compression test, all low, burning oil (camaroneil)
How much oil did you put in? The oil will take up room and raise your comp just from its displacement.
Have a hard time believing all your rings are bad, usually you find one or two that read low. How many miles do you have on the eng? Did you break the eng in and seat the rings (a few blasts to 5500 rpm's). Have heard if you don't get the rings to seat properly shortly after start up (within 500 miles) they will never seat properly but that might be urban legend.
Have a hard time believing all your rings are bad, usually you find one or two that read low. How many miles do you have on the eng? Did you break the eng in and seat the rings (a few blasts to 5500 rpm's). Have heard if you don't get the rings to seat properly shortly after start up (within 500 miles) they will never seat properly but that might be urban legend.
Instructor
Joined: Apr 2004
Posts: 166
Likes: 0
From: Troy MO
Re: compression test, all low, burning oil (camaroneil)
Well, a month old huh? How many miles have you put on it? Might not even have broke it in yet. Some of these new rings are slow to break in. Maybe its a reach, but brand new builds will use some oil, and have a little lower compression than when they actually wear to the cylinder walls. Of course there's always the chance that an e-bay purchased "rebuilt" motor may have been just re-rung with no boring when it was needed. I'll keep my fingers crossed for you.
Good luck,
Loren
Good luck,
Loren
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Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Re: compression test, all low, burning oil (TLChydraulics)
TLC there is totally correct in his observations,...and as a boost, my new engine back in '98 took an unbeefreakingleaaveable YEAR of daily driving to seat the damn rings, thing burnt oil like a ****.....had other kids of problems too, but got it all sorted out.....
after a year, it finally sealed up and was fine.....
you may want to pull a head or both, and look at the piston tops for numbers stamped in them...telling maybe a part # and how much oversize it is....
if nothing there, that is suspicious to me, anyway....then look at tops of the cyl walls to see if any wear lip there,
GENE
after a year, it finally sealed up and was fine.....
you may want to pull a head or both, and look at the piston tops for numbers stamped in them...telling maybe a part # and how much oversize it is....
if nothing there, that is suspicious to me, anyway....then look at tops of the cyl walls to see if any wear lip there,
GENE
