Reply To: Big 6 oil leak

[BernieParticipant]

Assuming it has not been modified, there is no seal at that point.  There is a “thrower” inside which is designed to deflect oil and the hole in the cover has a spiral groove to persuade any escaping oil to feed back down the shaft as it rotates.  Therefore, for the oil to be returned by the spiral, it is critical that the cap is fitted with the shaft perfectly centred in the hole, as the manual explains.

However, two of us have very recently rebuilt our engines and we have modified our covers to accept a modern polymer lip seal.  Both are leak-free.

The seal we used is a standard 50x60x8-R23-NBR Rotary Shaft Seal – Nitrile Rubber (NBR) Metric 50 x 60 x 8 which can be bought from most bearing suppliers for about £6 inc VAT.

The cap will then need to be machined to accept the 60mm OD of the seal.

B…………………..