[200q20v] crankcase pressure regulator valve

Phil Rose pjrose at frontiernet.net
Sat Aug 12 11:49:30 EDT 2000

Does anyone know the way to test that large, black plastic "pressure
regulator" valve, the one that's about 3" dia. and sits at the end of the
crankcase breather hose (behind the wastegate/turbo heat shield)? When I
removed this component the other day--while getting access to my
valve-cover--there was a 5 mm orifice visible through its sidearm. However
it wasn't obvious that application of either vacuum or pressure (applied to
either end) could get this internal orifice to change position.

According to SJM, high turbo speeds will produce enough vacuum at the
air-inlet side to cause the crankcase pressure-regulator valve to switch
from its 10 mm orifice to a smaller (5 mm) one. This implies that (with no
pressure differential) one should be able normally to see the larger (10
mm) orifice and not the smaller one that I saw. Comments?

So another question might be:  what is the symptom if this valve being
non-functional --e.g., if fixed in the small-orifice position? A recent
change I've noted (possibly related to the crankcase-valve question?) is
the fact that my Michelin Man hose has begun to contain large quantities of
oil, whereas it previously had been absolutely clean and dry whenever
inspected. This change in oiliness was noted soon after driving the car at
the Watkins Glen track event last month. It continues to accumulate oil
after normal driving.

Phil Rose				Rochester, NY
'91 200q				mailto:pjrose at frontiernet.net

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