''13. Worn Valve Stems and Guides
When wear has taken place on valve stems and valve guides, the vacuum in the intake manifold will draw oil and oil vapor between the intake valve stems and guides, into the intake manifold and then into the cylinder where it will be burned. If this condition is not corrected when new piston rings are installed, an engine is likely to use more oil than it did before because the new piston rings will increase the vacuum in the intake manifold. When gum or deposits on the valve stems are removed – a procedure recommended when overhauling an engine – the seal previously formed will be removed and leakage will be more pronounced. This is particularly true on overhead valve engines where loss of oil may occur on the exhaust valves as well as on the intake valves. High oil consumption caused by too much valve guide clearance can frequently be cured by reaming or nerraling the valve stem. In some cases new valves may also be required. Use of a permanently bonded valve stem seal will give added insurance against oil leakage on complete engine overhauls or on valve jobs.
Cantfind1- have a read you might learn something.
Might also explain why you have oil contamination in
your CSL Plenum and I do not.
Regards,
The Gorilla.
Is this an extract you made up yourself? Did you ever go to university?? Where is it from??
I am not doubting that worn valve stems will let some gas escape, however lets compare the size of a piston to a valve stem, which one is bigger Primate, or are you not evolved enough to work that out yet, you know square peg round hole and all that?!
90% of an engines blow by comes from passing by the piston rings and they do not have to be worn for this to happen it just happens whatever the state of the bores or the piston rings.
The reason why this gas is worse than the gas that passes by the valve stems is that
1 There is a lot more of it.
2 It passes straight down into the crankcase and mixes with oil fumes.
Valve stem seal gas escape is negligible and is basically exhaust gas, ie no oil vapour!
By the way you are right I have learnt something reading that.....You have absolutely no idea what you are on about!
Cantfind1- funny how when something contradicts
what Cantfind1 says, its dismissed or you spout
its made up, simply remarkable.
Worn exhaust valve guides can allow
excessive oil to pass by so its not just
''Gases'' as you allude to.
Size of the piston has nothing to do it with,
if you were running total seal intermeadiate
Rings but had worn valve guides /stem seals, the blow
by from the valve train would far more
excessive than the combustion chamber.
cantfind1- funny how when something contradicts
what cantfind1 says, its dismissed or you spout
its made up, simply remarkable.
Worn exhaust valve guides can allow
excessive oil to pass by so its not just
''gases'' as you allude to.
Size of the piston has nothing to do it with,
if you were running total seal intermeadiate
rings but had worn valve guides /stem seals, the blow
by from the valve train would far more
excessive than the combustion chamber.
Regards,
the gorilla.
yeah no one is running that!!!
And if they were then they wouldn't have worn valve guides because if they were that smart to fit new rings in the first place they would have checked the guides!!!
I do not believe I have contradicted myself
but if I have I apologize.
The reason why I got a little more 'excited'
than us Chilled Primates usually do was that
engine blow by can be caused for various
reasons. Its well documented.
While I enjoy good Technical debate as you
always learn something, hopefully, the introduction
of unrelated issues served no purpose and
one always wonders about the motive.
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