Primary drive venting

[AdrianS]

I've block off the chain oiler on my early a50.
I am a bit concerned re venting of the primary drive as I believe the oiler also acted as a vent for any pressure built up.
I've seen part 70-9800 which looks like a filler cap with a hole in it. Can anyone confirm that it is just a cap with a very fine hole drilled in it?
Also, my primary drive cover has what appears to be 2 holes adjacent to the 2 caps which are centrally placed on my chain case cover. Without removing the cover,can anyone tell me what they are for?
Cheers for any help
Adrian

[ChrisG]

The small hole in the caps is sufficient to relieve any pressure build up. There won't be much pressure as the oil seal keeps most of the crankcase pressure where it belongs. The two holes with caps were there for clutch adjustment. One for the centre, rod adjuster and the other so you can get at each spring adjuster in turn. They discontinued this on later models as getting the clutch to lift evenly by adjusting the springs needs to be done with the cover off so you can see the edge of the pressure plate when spinning.
I cant remember seeing any extra holes as described, can you tell us what dia. they are?

[AdrianS]

So is it ok just to drill a tiny hole in a cap ( I've got a couple of spare ones)?

I'll take a picture and post it showing the other 2 holes

[AdrianS]

Photo of chaincase

[DAVE BRADY]

I have found an image of another such case.  The holes correspond with two bosses on the inside of the cover such as on one I have but with no holes.  Marks on the case in the image seem to suggest that there was cover over the two caps ?

Dave.

[DAVE BRADY]

Hi,

Found another image with the cover this time.

Dave.

[AdrianS]

Thanks Dave. Clears up the mystery!