Clutch oil seal (1965 B40F)

[Phil C]

Hello all,  Looking for the source of a slight oil leak, I've just removed the circular plate which lives behind the clutch. Keen to have a look at the oil seal, I was interested to see that there appears to be a bit of damage to it. I was surprised because I fitted it a couple of years or so ago and the bike has done very little mileage since then (probably not relevant.) I don't know much about oil seals, but it looks to me (see pics) like the actual sealing lip is fine, but the other side (gearbox side) is damaged. Is that significant?  How could it have happened? I've got a replacement to put in, but would be interested to know how it might have happened and if it's significant.

You'll also see marks on the taper and (bush?) Running my finger nail across these, I don't feel any very obvious wear/depression, maybe a slight grooving on the taper. Hopefully the marks are not a concern?

Any thoughts/observations/advice would be much appreciated.

Phil.

[Blackthou]

Just a question, is the oil seal the wrong way round?

[Phil C]

Anybody know? (see photos)

[PeteRae]

Reckon its the right way round Phil...its purpose is to stop, or slow down, the oil escaping from the primary case. Did you have the big fluffy washer fitted between the sprocket nut and the plate? It soaks up some of the oil but might also keep rubbish off the seal face. You'll get all sorts of road rubbish flung around the sprocket that could do that kind of damage!
Pete.

[Phil C]

I'm sure I would have checked when I fitted it that it was the right way round.

Yes I had a felt washer behind the plate.

Thanks.      Phil

[Phil C]

I'm sure I would have checked when I fitted it that it was the right way round.

Or of course I might have just made sure I fitted it the same way as the previous one had been. Just checked Rupert Ratio and Haynes and service sheets: can't find any indication of which way is right.   Phil

[Pete A10]

Oil seals are normally fitted with the lip facing the side where you want to retain the oil

[Phil C]

Does it look the right way round on the photos?

[PeteRae]

yup....the lip/open side is facing the clutch.
If you put it in the other way it will  try to fold in when you push it over the shaft.
Pete

[Phil C]

Thanks Pete.   Phil

[Phil C]

Yes, just come across it in RR, p.101.  Phil

[Blackthou]

Sorry for any confusion, just asking a question in case.

[Phil C]

Worth checking, thanks Rick.  Phil

[PeteRae]

Its easy to put it in the wrong way guys.....holds hands up
Pete