18 replies to this topic

[brivinci]

Finally found the correct size socket to torque the 3rd motion shaft nut down and then I will be on to the diff. I took this unit apart a bit ago and cant remember which surfaces get gaskets and which just use gasket maker. Can anyone tell me for sure?

Thanks

[orcadian]

There is a gasket at the top and bottom faces of the diff where the two halves meet, that's two there, then there are gaskets where each diff flange fastens to the main housing (that's two more) and then there are 2 oil seals where the drive flanges fit through. There are also lock tab washers on the diff casing (on earlier cars) and individual locking washers on the diff flange bolts. Don't forget the original diff shims which you took out and noted their exact position when you dismantled it.

[brivinci]

Right but on the later cars they didnt use actual gaskets on some I thought. Some were put together with gasket maker only. Now, if this was because they were being cheap, I'll use the gaskets I have but if this was done for a specific reason, I would like to rebuild the right way.

[samsfern]

minispares sell gearbox gasket kits, ive never heard of them not using gaskets, itll just leak out everywhere id have though. when i done some bits to my gearbox i used gaskets and a light smear of blue hylomar on both mating surfaces.

Edited by samsfern, 21 November 2010 - 05:51 PM.

[brivinci]

Ok, that is what someone else had said they used. Some people only use a gasket maker without a gasket and have good results. I am not looking to cheap out as I have the gaskets already, I just want to get it back together the exact way it came out.

[Southy]

I build Mini Gearboxes and I use gasket maker on the diff nose cone itself and then just apply a large blob of gasket maker where the indent spring sits against the diff output cover

I've never had any issues with any oil leaks from the nose cone or the output cover.

Edited by Southy, 21 November 2010 - 07:04 PM.

[brivinci]

What exactly is the diff nose cone?

I just picked up some Hylomar gasket dressing and was going to use that (a very thin skim) on all the gaskets for the diff. I understand about the indent spring though.

[Southy]

The diff nose cone is the housing which sits on the back of the gearbox which encloses the diff itself in.

to be honest I don't like Hylomar, I don't think its upto the job I prefer to use a sealer such as this http://www.caarbitz.co.uk/Wynn's_Black...200Ml_57680.htm

[Ethel]

The diff and gearbox casings are assembled and machined together, if you add a gasket where there wasn't one you will alter the fit & clamping of the output shaft bearings. If in doubt, I'd use a bead of sillicone RTV and no gaskets.

You will need gaskets on the end covers - use decent (i.e. genuine) ones as they need to be the specified thickness to set the diff preload correctly.

[brivinci]

The diff and gearbox casings are assembled and machined together, if you add a gasket where there wasn't one you will alter the fit & clamping of the output shaft bearings. If in doubt, I'd use a bead of sillicone RTV and no gaskets.

You will need gaskets on the end covers - use decent (i.e. genuine) ones as they need to be the specified thickness to set the diff preload correctly.

Thanks, can anyone tell me whether or not a 94 A+ gearbox would use a gasket or not on the diff cone? I just built it with a gasket and very thin smear of sealer, then torqued down slowly around all bolts. Need to know if I have to go back and redo now.

[Ethel]

There are none shown in the workshop manual, Guessworks will know better.

[Sprocket]

all 1990s transmissions SHOULD NOT have diff housing gaskets, but then you never know who has been messing with it in the last 15+ years!

If the diff case is retained by bolts chances are it should have NO gaskets, if it is retained by studs and nuts, chances are ith SHOULD have gaskets. But of course if the box has already been apart and built by someone ignorant of this fact could have used gaskets where there shouldnt be, or replaced the studs with bolts, although why you would I can't quite figure out.

If in doubt, use a bore gauge to check the diff bearing housing roundness with the diff cover bolted up without gaskets and then with gaskets.

diff side covers - they do not necessarally need gaskets, but you will need to carefully shim the diff. In all honesty you need to carefully shim the diff even if you use gaskets as I have not seen a gasket recently that comes close to the original Austin ones, and that includes the so called genuine Rover gaskets.


Don't use Hylomar, use Loctite black RTV instead

Edited by Sprocket, 22 November 2010 - 09:09 PM.

[Guess-Works.com]

RTV should only be used on the diff cover if it has a DAM* part number cast into it.... if it's a 22G* casting then it will require gaskets...

NEVER use RTV, Silicon or any other splurge on any other surfaces as you're likely to block oil ways, especially to the diff side cover bushes... If you want to use something to hold the gaskets in place, then a wipe with some multi-purpose grease is a non-intrusive solution...

and always make sure your gasket faces on the parts are clean and free of old gasket and goo

[brivinci]

RTV should only be used on the diff cover if it has a DAM* part number cast into it.... if it's a 22G* casting then it will require gaskets...

NEVER use RTV, Silicon or any other splurge on any other surfaces as you're likely to block oil ways, especially to the diff side cover bushes... If you want to use something to hold the gaskets in place, then a wipe with some multi-purpose grease is a non-intrusive solution...

and always make sure your gasket faces on the parts are clean and free of old gasket and goo

Thanks a lot. Ordered a new set of OEM diff side cover gaskets and going with no gasket for the diff case/nose cone itself. Any recommendations as to what type of sealant to use on that? Also, is the torque settings right at 18 foot pounds?

[Ethel]

Use RTV, Guessworks is saying don't use it on the end covers as they have oilways through the joining surface that could be blocked