Diaphragm oil leak

[paull]

I’ve got a persistent leak from one of the transmission chambers from around the diaphragm. I’m fairly sure the diaphragm is good condition with no splits.
has anyone got suggestions on how I could improve the seal? I’ve tried cleaning it, and putting a smear of grease, but both times the leak has returned

[andrew]

What Daf do you have? Daf 46 and 66 cars have a De-Dion rear axles opposed to the swing axle arrangement on earlier cars. Although this doesn't affect the transmissions per se the belts are longer on the earlier transmissions, so allow for the twisting action of the axles. This in turn may reflect in a different design of the transmission units themselves.

Where is the leak appearing? Happy to advise on the earlier transmissions, if you're able to explain precisely where the leak is from.

[dafman50]

If leak is from covers the culprit will be the cone internally. If from rear it's the oil seal .

[paull]

Hi there, I should have said it’s a Volvo 66.
The leak is from the covers around the edge of the cover where it’s held on with the big circlip wire thing, not the centre

[swissdave]

Hi Paul, I've had a leak there on my V66, first time was a diaphragm second time it was the rubber cup seal inside the domed cover of the primary drum.
Other than a damaged outer cover I don't know how else it could be getting out.
I take it you've tried the blow test to see if the diaphragms are sound?

[paull]

Thanks Dave that’s a good idea, I hadn’t tried the blow test. The confusing bit is that it seams to have leaked while sat still