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1275 PCV valve and oil leak

abarth69

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Can anyone explain this?

When I hook up my new pancake style PCV valve up to front timing cover of my rebuilt 1275 I get a leak at the rear engine seal. Drip Drip Drip. Now when not hooked up there is no leak at the rear seal.

I thought these PCV valves helped keep the oil in the engine.

Cheers

Mark
 
The Bentley manual stated "that with a warm engine at idle, remove the oil filler cap. A rise in engine speed, the change being audibly noticeable, indicates that the control valve (PVC in your case) is functioning correctly. If not service the valve (PVC in your case)." this is written for the PVC valve (Lucas pancake type), but it should work the same for your's. Do you have the plastic vented oil filler cap?
Scott in CA
 
Yes it is the Lucas type just got it new from Moss. I would say the filler cap is not vented.


Mark
 
Try the test anyway. the idea is to draw the crankcase gases through the PVC valve and into the intake manifold. With the cap off, there is no restriction on the flow, and the idle increases due to the additional air/crankcase fumes flow. The vented oil filler cap with its small vent hole reduces the amount of air, and the resultant idle speed. I think that you don't have a way for air to enter the crankcase, thus no flow to pull the fumes out. Hope this helps.
Scott in CA
 
There is a replaceable membrane/insert/valve in there I think. Could it be installed backwards?
 
To assemble:

Install spring
Install valve, stem first
Install diaphram, location ridge around the outside of the diaphram first
Install cover
Install wire bail
 
abarth69 said:
Yes it is the Lucas type just got it new from Moss. I would say the filler cap is not vented.


Mark
That filler cap should be vented... check to be sure :smile:
 
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