Jag diff rear cover seal

[richardd]

Hi Guys,

I have now tried to seal the rear cover plate on my Jag diff 3 times and I still get a slight weep. And this is whilst it's still in the garage and not subjected to road use.

I've twice sealed it with black RTV, cleaning both surfaces with acetone and the last time I bought an original paper gasket and applied RTV to both sides.

Still a weep and it is always at the bottom.

The cover plate looks pretty straight but when I take it off next time I will put a straight edge across it but I would expect the RTV to fill any gaps.

Am I tightening the bolts too tight and squeezing all the RTV out. Should I partially tighten and then finally tighten once the RTV has cured?

Any other thoughts or ideas???

[kdavies3]

Am I tightening the bolts too tight and squeezing all the RTV out. Should I partially tighten and then finally tighten once the RTV has cured?

Any other thoughts or ideas???[/quote:f2f1a28da9]

I reckon you got it in one, a decent bead of RTV (no gasket) should do it, but only lightly tighten the bolts.

Are you sure it isn't the pinion seal weeping or the output shafts?

wherever the leak is it will always run to the bottom of the diff.

[Clive]

Hi Richard,
Make sure you tighten the bolts gradually and in opposite diagonals (ie top left, bottom right, top right, bottom left etc)
Cheers, Clive

[wilf]

Also, it could just be that the breather is letting a little oil past, not unknown.

[richardd]

Hi Kevin,

It's definitely coming from the bottom edge of the cover. I have kept an eye on it for several weeks and kept wiping with clean kitchen roll. The diff is clean and powder coated so it is easy to spot weeps.

Hi Wilf,

Unfortunately it is still in chassis build and has not been run in anger. This is why I'm a bit concerned as what is going to happen once it gets warmed up with power going through it?

Previously I have used the small tubes of Halfords RTV, going off down the Motorfactors and buying the bigger tube to fit a mastic gun I have. This should put a decent bead all around.

I'll let you know how I get on.

[ldtopham]

Richard I had the same problem also. In the end I used a polyurethane sealant (sikoflex) and it doesn't leak any more. Sticks like **** to a blanket that stuff:thumb: .
The above advise will make the seal much more efficent.
Good luck. After leaking for a second time with only the lightest of hylomar as a seal I now dread looking under the car everytime I enter the garage. 6 months on and it aint leaking doubt it will ....... until I get it on the road and can't get to it anymore

Good luck,

[skorpion]

Have also a leaking jag diff..looks like it is the breather.
can I resolve this ?
Regards,
Andy

[richardd]

Hi Lee,

Is Silkoflex a trade name? Do you get it from a Car shop or Builders merchant?

[kdavies3]

Richard, Sikoflex is a trade name but it's basically RTV.

A 3-4 mm bead should do it. It's worth circling the bolt holes too as well as the main cover ring.

[richardd]

Hi Guys,

I've just found a tube of Loctite 598 black silicon flange sealant in the back of the workshop so I'm going to give this a go tomorrow.

As you suggested Kev, a good healthy bead and around the bolt fixings. I think I will just hand tighten until it has gone off and then finally nip up with a spanner once it is dry.

I'll let you know how I get on.