Oil Filler Cap

[Roger GrixParticipant]

The oil filler cap on the Perfo rocker box with its spring clips seems to be designed to drop the oil vapour that collects on its underside onto the rocker box.

It then runs down into the specially designed gutter where it sits until it is full enough to run down the engine.

I thought that I would fix it and installed some U channel “rubber” around the rim of the filler and re-fitted the cap.

It seemed to work but then I started to worry that I might be stopping any water vapour in the engine from escaping. (Not sure if there should be any water vapour  – probably not but if there is – better out than in.)

I also wondered whether there might be a slight pressurisation in the rocker box and what that might do.

Any comments?

Roger

 

[ChrisParticipant]

Interesting idea. The crankcase is vented by its own tube on the side of the block so it won’t cause a problem to that part of the engine.

I would think that if you developed too much pressure in the rocker box the oil filler cap would lift up. I think that might be the only risk.

Let us know how it goes.

Chris

[BernieParticipant]

I cut a disc of open cell (very important) foam, about 15mm thick which fitted snug,y inside the cap.  This worked very well, catching any oil and preventing it being ejected.  I cleaned it in petrol every oil change.

Although the sponge was retained by the springs in the cap, there was a perforated plate in the rocker cover that would have prevented it from entering the cover had it come adrift.

B….

[Roger GrixParticipant]

Thanks Bernie,

That sounds like a good alternative.

Roger

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