Moss box help

[mxke]

I cleaned up and resealed the Moss box in my 1962 OTS when I had the car all apart.
The box remained sealed until I hit around 300 miles on it.
I now have a leak at the back of the gearbox and it appears to be in the area where the counter shaft and reverse shaft protrude and get locked in place by the plate.
The rear seal is not leaking.
What did I miss when I had it apart?
Thanks in advance.
Mike

[Simonpfhc]

Hi Mike,

There are only three places oil can leak out the rear housing - the gasket, the speedo drive or the rear seal. Are you sure it’s not leaking from the top cover or selector rod and running down the sides?

[dxke38]

if as you say its coming from around the layshaft and reverse shaft locking plate it could be the O ring seals on these shafts.

[mxke]

Can one replace the orings in situ, or is it a engine out job?
Just curious if the aluminum rear end cover (C21415) can be pulled off and the orings replaced, or does the box need to be dismantled to replace them?

[mgcjag]

Have a look here...very good info https://forums.jag-lovers.com/t/leaky-m ... its/441008 Steve

[mxke]

Would anyone have the dimensions or standard O-ring sizes for the two sealing rings for the countershaft and reverse shaft on a Moss box?
Jaguar numbers are C4284 and C4285.
I’m thinking #208 and #209 in standard O-ring size?
Thank you in advance.
Mike