Leaking gearbox

[Goslima1]

Have just completed my R300 build and road tested car last night for a mile or so - very nice

 

However went into garage this evening and there is a very small puddle of oil under gearbox. Closer inspection reveals the leak is coming from the speedo drive - the leak is not around the brass 'top hat' but the oil is actually travelling along drive into sender unit and leaking out along thread. There is no washer between speedo sender and brass 'top hat' although on closer inspection the sender unit does look like it has slight ridge for one - so a number of queries:

 

1. Should there be a washer ? if so, rubber or otherwise ?

2. Should oil travel along the sender spindle into the housing ? Could this damage the sender unit ?? If not does this mean I've assembled the speedo drive incorrectly ?

3. Is there any reason I can't put a rubber washer in here anyway to stop leak ???

*confused*

 

All comments gratefully received - car is going to CC for PBC on Friday.

 

Marty

 

[Nigel Riches]

Marty, whatever type of gearbox you have, it shouldn't leak from anywhere, (in a perfect world), there should be an oil seal in the tailshaft housing, where the speedo drive shaft gear exits the housing, these are quite small, about 18mm diameter, if we're talking Ford based gearboxes, and this seal is the most likely point of leakage, I would think the sender won't benifit from have transmission oil jammed in it, some lubrication good, to much, not good, as for the question of washers, I'am sorry I have no answer. Get CC to check the oil seal at PBC, as they can be a prick of a thing to change in situ. Regards Nigel.

 

1982. 5 speed, clamshells. B.R.G / Ali. The True Colours.

[Goslima1]

Thanks for the reply.

 

I've searched on BC and posted on R300.net and low and behold this seems to be quite a common problem, particularly with the 6 speed box. It appears the seal either decides its going to be oil tight or not. I called CC technical help yesterday who also confirmed this is not uncommon - they tell me the 6 speed box was designed to use a Ford seal which is no longer manufactured thus an alternative was sourced which may not be so robust.

 

The good news for me is that it has stopped - after a short spin last night there is no oil on garage floor 😬. However I do now expect this to re-occur in the future !

 

Marty

 

[micksmetafors]

I have similar situation on a 6 speeder which had a new drive ratio put in. Apparently the genuine Ford oil seal for the speedo drive isn't available and the substitute isn't as effective.

Seems like permanent dribbling might be the situation.

 

 

[Wahey]

same problem here too. Been told I need a new speedo drive thingy. I may not bother if new ones are doing it too. Very minor leak though.