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1991 Chevrolet Silverado Repair Question


Topics covered: Smoke, Compression, Engine.
Mileage: No information provided.

Asked on April 4, 2008

1991 Chevy Silverado oil useage


truck sat for 3 years runs real good no oil leaks compression is 195 all cyls. smokes a little when it is started could this be a head problem or bad oil rings uses 1 qt. of oil 100 miles does not smoke on the hiway where is the oil going.
Avatar Asked by luckyjimmy1951

Answer

Replied on April 5, 2008

Hi there,

The smoke on start up is a good indication of worn vale stem seals and valve guides. Although you have good compression, the oil control rings may be suspect and a small but constant oil burning may not be visable, a good indication is when you back the throttle percentage off ant high way speed, this will give a very high engine vacuum reading and faulty rings ill show up with a puff of blue smoke then. you can try moving up a weight in the oil viscosity a well.
But oil consumption , if not an external leak, it's going out the exhaust.

Mark (mhpautos)

Tiny Answered by mhpautos (expert)
26,913 answers provided
Replied on April 5, 2008

Try this with a vacuum gauge hooked up to identify ring/s and oil control problem. Or use a compression gauge/leakdown tester

When throttle is opened and closed rapidly and needle falls to 0 and rises to only 24 or less inch


http://www.2carpros.com/forum/automotive_pictures/12900_vac5_1.gif



HTH plus the earlier suggestion by Mark

Tiny Answered by rasmataz
68 questions asked