440 Manual Gearbox oil problem
 

I have had the gearbox apart to replace the leaking front oil seal but now the gearbox blows oil out of the breather tube after half an hours running. Can anyone help with this please.

That sounds like a case of overfilling tbh... If that is the case, its good there is a breather and hasnt blown the seals out making you do the job again! :)

Thanks Andy for reply. I first filled the gearbox with oil to the bottom of the filler plug and had the oil leaking out the breather so then I tried dropping the level 1/2" below the filler plug - still blowing oil out the breather......
I originally removed the gearbox and replaced the engine rear main oil seal and dismantled the gearbox and replaced the combined front input shaft seal/ bearing. This car has no previous history of blowing oil out the gearbox breather so I feel I have "created" this problem.

Well there has to be some kind of pressure building up/fluid rising in one way or another...
How much did you rebuild the box? Wondering uf something is tight and overheating...?

you mean the filler plug half way up the front side of the gearbox ? how much oil actually went in , about 3.4 litres ?

Thanks Andy for reply. If you think something is tight or binding inside I guess the only way to establish that is to pull it apart again.....the gearbox feels really smooth to drive and shift etc so it doesn’t feel like there is a problem inside but I guess something is not right somewhere to cause my issue.

Thanks Clan. Yes the filler plug half way up the front of the gearbox. The first fill was about 3.4 litres so it seemed correct.