R80G/S & ST Bevel box Seal

[England-Kev]

When changing the large bevel box seal behind brake shoes, can you change it in situ, or do you need to remove the cover to do it. also apart from the seal and possibly the cover gasket, are there any other parts that need to be ordered also.


I have a leak you see, and I am not sure where from, I am hoping it is the brake cam shaft again, ( I only changed the o-rings last year) so I am going to replace the shaft o-rings, and run it to see if it leaks again. something has let go though, as my rear tyre got covered in oil today, I will post pictures in a while.

 

[England-Kev]

Well now who'd of thunk it?

I found the cause of said drive oil leak, after stripping, cleaning and replacing the o-rings, I put it all back together, drained off the rest of the oil, and refilled with new. it was then that I found the breather in the filler, was well, not breathing, it had managed to get full of rust.
So the drive had become pressurised, and with this hot weather, it blew out past the brake cam o-rings. So I now have a new breather on order, and a spare set of o-rings.

 

[Canuck]

Thanks for posting this up... its a good reminder and advice for others with similar problems.

 

[England-Kev]

I ordered the replacement o-rings from MW £10 for 4 small o-rings

 

[England-Kev]

When changing the large bevel box seal behind brake shoes, can you change it in situ, or do you need to remove the cover to do it. also apart from the seal and possibly the cover gasket, are there any other parts that need to be ordered also.

So anybody have an answer for this?

 

[dr nosh]

England - Kev.

Just been through similar.

See in another thread last week.

The O rings that I required (80ST) were 4, 2 in each bush (the bush is in 2 pieces pressed into the outer case and into the inner case.)

Actually ordered the incorrect 'thinner' section rings to start with.

When I pulled the cam//shaft out, I lost about 30 cc of oil. Leads me to believe that the stated volume is too much and so the box is overfilled.
General agreement from others in other thread.

I have let the oil settle so its just at the bottom edge of the bush.

New rings, good clean up and 100 miles later its OK.

Good point about the breather being blocked. I'm going to check that.

Can't really tell you much about changing the large oil seal as mine was 'dry'. It does look like you can remove the inner part of the box and change the seal. There may be a gasket between the 2 halves.

 

[England-Kev]

When I pulled the cam//shaft out, I lost about 30 cc of oil. Leads me to believe that the stated volume is too much and so the box is overfilled.
General agreement from others in other thread..

The box is not overfilled, this is why you need the o-rings and as such you will always loose oil when pulling the cam spindle, to stop this just drain the oil first. Which in itself is good practice, as you can check the drained oil for metal particles.

As any of you who have read the post I made above will have concluded, the drive gets hot, and so the oil is not just for lubrication, but also for cooling, so make sure you replace the correct amount, this is why you have a breather built into the filler plug