968s sucking oil into engine somehow???

[Jake Raby]

The AOS is internally baffled.

What kills the AOS more than anything is oil selection coupled to extended oil service intervals that kill the membrane inside the AOS.

[piersman]

Originally Posted by Jake Raby

In my experience the smoke that is emitted from these engines when cornering IS NOT the fault of a scavenge pump. I see this condition routinely and have only had a scavenge pump replacement dove it in the instances where a scavenge pump has failed.

Hi Jake , thanks for your comments. You said the above before going on to explain the impact of a pump being seized by engine parts.

What is(are) the cause(s) of cornering smoke that you've found? Something on my car is causing the AOS to suck up and throw large amounts of oil into the engine when 'pressing on' , particularly if having just exited a left hander.

What oil do you recommend? The AOS is 3 months old.

Thanks

[Jake Raby]

Originally Posted by piersman

Hi Jake , thanks for your comments. You said the above before going on to explain the impact of a pump being seized by engine parts.

What is(are) the cause(s) of cornering smoke that you've found? Something on my car is causing the AOS to suck up and throw large amounts of oil into the engine when 'pressing on' , particularly if having just exited a left hander.

What oil do you recommend? The AOS is 3 months old.

Thanks

Either you have a bad "New" AOS (which we see all the time when testing with a Manometer) or the valve stem seals are hardened and allowing oil past them.

This is what happens with the glorious engine oil and service intervals dictated by the factory.

Hardened stem seals allow oil to be sucked past the intake valves during heavy manifold vacuum. Oil that puddles in the cam covers from G force aggregation can also leak past exhaust stem seals and end up in the exhaust system.

Worn valve guides can have a similar impact as the excess movement in the valve impacts the ability of the stem seal to do its job.

[seningen]

Originally Posted by Jake Raby

Either you have a bad "New" AOS (which we see all the time when testing with a Manometer) or the valve stem seals are hardened and allowing oil past them.

This is what happens with the glorious engine oil and service intervals dictated by the factory.

Hardened stem seals allow oil to be sucked past the intake valves during heavy manifold vacuum. Oil that puddles in the cam covers from G force aggregation can also leak past exhaust stem seals and end up in the exhaust system.

Worn valve guides can have a similar impact as the excess movement in the valve impacts the ability of the stem seal to do its job.

Not to question the above which are all good suggestions/observations:

Could Ovality come into play here causing blow by which is overwhelming the AOS?

If so -- what is the easiest way to check?

Mike