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PCV Valve Question

S

sab

Regular Contributor
I'm going through my newly acquired 2004 350 Mag MPI, and on my list is replacing the Positive Crankcase Ventilation (PCV) valve. The one I removed from the engine is 100% plastic and you can stick your little finger almost right through it. (The vent tube is a corrugated like the ones you protected wire runs with) The PCV valve I got from mercury (P/N #21-8M2017060) has a metal base with a check valve in it, and a different diameter vent hose. I'm assume the mercury one is the correct part that should be installed (need a new vent hose). I'm not looking for problems. Maybe they had problems so they installed the hollow PCV? Comments?
 
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marine engines run at high power settings and there is very little vac to pull the blowby out of the engine .
To keep the fumes in check the hose it just directed at the flame arrestor
 
I installed what I believe to be stock OEM PVC and new (fuel type) vent.
Next issue - I can't get get the oil filter off. I replaced over 300 filters in over 30 years. Bent the handle of my oil wrench and starting to crease wall of the filter with 3 foot persuader/pipe on on the wrench. Afraid I going to snap mount/fixture if I force it. Hopefully engine starts today and will try again with hot engine/oil. It a Purolator - I wonder if its the right type or it was leaking
 
If this is a remote oil filter that happens a lot.You will need to use heat where the rubber gasket is then use the wrench
 
If you cant get it off in a normal manner then you will have to destroy it and get it off the best way you can.........Been there and done that a few times.

Some even from the factory!!
 
Jack- thanks I need to get it the engine started and the oil/gasket hot before try again, first, before I drive a screw driver through it. Worse come to worst I'll let the Northshore repair shop do it - I will snap the whole assembly it If I try with the persuader and it is remote as BTDoctor commented
 
Driving a screw driver thru it not terribly effective as the very thin sheet metal will tear. The one and only time I had this happen on my boat I had to end up using a chisel to drive the base plate of the filter with a hammer, which is the strongest metal on the filter. Now... I always "lube" the rubber on both oil and fuel filters with a very thin film of oil and make sure that the mating surface of the filter is clean and free from crap and any burrs.
 
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