Cylinder wear and oil consumption
June 16th, 2018, 9:53 AM
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Cylinder wear and oil consumption
Hi
I was hoping i could get some input from an engine machinist. I have a serious iol consumption issue on a rebuilt 350. used oil since new rebuild. .030 over with new Edelbrock top end kit. Wondering if it could be coming past the rings. Had heads gone through and replaced intake gaskets twice. Re-ringed motor but nothing changed. It has 10000 miles on it. It is in a 83 2500 Suburban
Thanks
I hope these pics come through.
Dennis
I was hoping i could get some input from an engine machinist. I have a serious iol consumption issue on a rebuilt 350. used oil since new rebuild. .030 over with new Edelbrock top end kit. Wondering if it could be coming past the rings. Had heads gone through and replaced intake gaskets twice. Re-ringed motor but nothing changed. It has 10000 miles on it. It is in a 83 2500 Suburban
Thanks
I hope these pics come through.Dennis
June 16th, 2018, 10:38 AM
#2
the time to test for oil consumption past the rings would be before teardown; performing dry and wet compression tests. Maybe its the picture quality; to me the cross hatch pattern doesn't look so good.
any blue smoke out the exhaust?
did the spark plugs have any deposits on the center electrode...if yes, check the valve stem, seals.
any blue smoke out the exhaust?
did the spark plugs have any deposits on the center electrode...if yes, check the valve stem, seals.
Last edited by tech2; June 16th, 2018 at 10:42 AM.
June 16th, 2018, 2:47 PM
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Thanks for replying. There was little or no blue smoke on start up. Nothing to speak of when you were driving. We had the heads redone once since we rebuilt the motor and of course they were new when we installed them and it didn’t make any difference. Plugs were fouled terrible. There was oil on top of the valves when we opened it up. And the valves were all oily and crusty with build up After just 1000 miles.
Cylinders #6 & 8 were the worst but all had black crusty plugs.
We did do a compression check and all eight cylinders were all within 10 pounds of each other and they were around 170-180 psi.
Cylinders #6 & 8 were the worst but all had black crusty plugs.
We did do a compression check and all eight cylinders were all within 10 pounds of each other and they were around 170-180 psi.
June 16th, 2018, 5:04 PM
#4
its either the rings or the valve stem seals...if you have good compression and the wet readings did not differ much...ash on the electrode of the spark plug...i'd be looking at valve stem seals or issues with the valve stem clearance. any blue smoke at start up?
June 18th, 2018, 8:56 AM
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Very little blue smoke on start. We’re taking block back to engine shop to have them look at it first hand. A couple good mechanics here suspect the cutters were chattering when boring was done. Heads were new Edelbrock alum and they were so crusted up we sent them out to be cleaned and inspected
