Hi Trevor Boicy!!
On Fri, 23 May 1997, Trevor Boicey wrote:
> Well, the oil pump is constantly sucking volume out of the
> sump for one thing. The oil finds it's way back, but not
> right away, especially oil pumped up to the rockers.
I think you're confusing a dual scavajing pump dry sump system with the
"B"'s wet sump, single pump.
> From my experience, most modern engines run with a slight
> crankcase vacuum at all times. This is of course with PCV
No Trevor, that is not possible. There will ALWAYS be ring blow-by into
the crankcase, creating a POSITIVE pressure off-idle. The wider the
throttle, the more blow-by.
> valves, but a PCV valve will only keep the pressure
A pcv valve controls MANIFOLD vacuum, of which there is very little at
wot, and also less than normal with a "hot cam" at idle.
> "no higher" than the air. From whatever mechanism, it tends
> to be a bit lower than the outside, a slight vacuum.
See above.
> I wish I had more technical reasoning, this is all
> observations, and a wild stab with the oil pump.
Trevor, you've never had the pleasure of driving a beater. Those
engines don't "weep", they ooze, and drip. The pcv valve can't keep up
with the pressure from the ring blow-by.
TTUL8r, Kirk Cowen (who was once audited by Revenue Canada for
claiming oil expenses to drive from Vancouver to
Calgary for a convention. 11 gallons going, and
9 gallons returning. Aha says the auditor, why
only 9 gallons returning?? Oh, says me, 'twas all
downhill coming back!! I got the allowance.)
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