Sigma Oil Leak

[alcal]

Just had a look under my recently bought 3 year old car and there is a small leak from what seems to be the join between the gearbox and bell-housing. I'm not sure if it's engine or gearbox oil but the drip on the casing was clean and greenish leading me to suspect gearbox. Should I be concerned ?  There is a silicone bead around the join - is that normal ? Grateful for any advice.

[Jonathan Kay]

Which gearbox?

There's a known issue with the seal around the selector shaft. But the advice is split across multiple threads.

Jonathan

[DJ.]

There have been a few reports of this. When I built my Sigma engined 5 speed Seven, there was a paper gasket to go between the bell housing and gearbox to which I also applied sealant.

If I remember correctly, there is a shaft that comes out of the front of the gearbox and into a blind hole in the back of the bell housing and the oil you are seeing is coming from this. It is an engine out job to sort it, but it is likely that the oil loss is minimal, so I would suggest you top up the gearbox, run if for say 500 miles and then see if it needs topping up. You may well find, you only have to do it once a year.

I have a drip from the nose of my diff, but it isn't worth the aggravation of removing it as I only top it up every couple of thousand miles.

[alcal]

It's a 5 speed type 9 Jonathon. Even though it's under waranty I'd rather not take it back unless I thought the clutch might become contaminated and would be interested to hear if anyone has experienced this.

[ChrisC]

Hi alcal 

I have exactly the same problem as you decribe last year.  The builder of my car decided to leave the gasget between the box and bell housing dry, leading to the leak.

I am local (ish) let me know if you need any help or advise. 

Chris.   

[SM25T]

If under warranty .... why not take it back. It won't get any better ... until it runs out of oil !