Diff pinion leak

[80Sprint]

I have fitted a new seal to the pinion and soaked it before fitting. It leaked on the first trip. It seems to be coming out of the joint between the prop and flange so I would have thought it would be leaking nearer the casing if the seal had gone. Not had a chance for a full inspection yet but can oil get to the nut area and if another seal leaks could I seal the metal cap ?

[Richard the old one]

I have noted the same problem with one of my 1500cc dolomites. I believe the oil was coming down the splines as when I put some silicon sealant between the prop shaft / axle coupling it stopped. This was an easy way to stop the leak without having to dismantle it any further. I assume the cap over the nut is there to stop the leak but obviously it can get distorted when you take it off.

[Mad Mart]

If oil is still leaking after replacing the seal either the new seal was already broken, the seal was broken on assembly or there are gouges on the diff housing where the seal has been removed in the past?

[80Sprint]

I am suspecting the latter Martin as I don't think I did any damage around the area or seal. I must admit though I did not give the shaft a thorough inspection before reassembly as the diff was not completely stripped. I still would have thought it would leak further back but may have to try some sealant until I can get the axle out again as it sounds like a full strip down if the shaft is damaged.

[Mad Mart]

There are only two places it can leak past the seal Mike, on the outside of the seal (uneven surface on casing) or the inside of the seal (uneven surface on the pinion flange), unless the pinion flange has a crack longitudinally?