compression #s and oil burning

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Aug 12, 2001 | 04:07 PM

rwjr

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From: Athens, AL

compression #s and oil burning

i am burning a quart every hundred miles, so i did a vacuum and compression check....the vac reads at 19" and steady...the compression check low was 125, high 150, indicating ,i presume, good rings and valve guides...what gives??????????

Aug 12, 2001 | 06:50 PM

tetraruby

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compression #s and oil burning

Check the PCV to see if it's clogged or restricted. Try a higher flow PCV valve.

Aug 12, 2001 | 07:05 PM

jowilker

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From: Creedmoor, North Carolina

compression #s and oil burning

Rodney, How much of that qt. might you be leaking instead of burning?

John

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Aug 12, 2001 | 08:46 PM

rwjr

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From: Athens, AL

compression #s and oil burning

there are no external leaks...i get an occasional puff of smoke on startup, but only once in a while....

how do i differentiate a higher flow pcv valve???and what exactly will that change?

Aug 12, 2001 | 09:04 PM

karljay

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From: Northern California

compression #s and oil burning

[font size="1" color="#FF0000"]LAST EDITED ON 12-Aug-01 AT 10:06 PM (EST)[/font][p]If your plugs have oil on them, I'd look at the valve stem seals. Your compression is not too bad and you say your not leaking that much so I'd guess the intake is sucking oil thru the valve stem seals.

Most old valve stem seals are simple rubber, I put positive seal types on mine because FE engines are known for poor stem seals.

By the way, which engine are we talking about? And what mods have been done?

Aug 12, 2001 | 11:35 PM

rwjr

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From: Athens, AL

compression #s and oil burning

[font size="1" color="#FF0000"]LAST EDITED ON 13-Aug-01 AT 00:38 AM (EST)[/font][p]it is a 429...the plugs have a little oil on the threads, but that's it...so the seals could be hardened, i guess???to replace them, i can place each cylinder at TDC and remove the springs that way, right??

oh and it has edelbrock performer intake, 600 cfm edelbrock, edelbrock chrome dress-up, but as far as internally, none that i know of, but i am SLOWLY building another big block to replace it....just depends on what i can do about this oil thing...and if i can find a good source for a 429 or 460 crank....

Aug 13, 2001 | 02:44 AM

BigBrownTruck

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compression #s and oil burning

Is your valve cover baffled? I had some aftermarket chromies on a 302 once that weren't and it sucked voracious ammounts of oil through pcv valve when at higher RPMs on freeway... all stopped when it got properly baffled valve covers. I also had a 390 that was going through oil quickly , but it was a smokin.... and when torn down had most of the oil control ring from #7 in the bottom of oil pan as well as broken off skirt.

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