Another GKN diff question.

[The AJP Griff]

Recently found that the cause of my leaking output shaft seal is some pitting on the surface of which the seal runs(i think this is a spacer?)
I've had a couple of good used ones arrive and i'd like to replace the bearings as a matter of course.Is the spacer i refer to,which sits adjacent to the bearing,known as a collapsable spacer?If so,what is its colapseable puprose and how do you remove it without damaging it so that it can be re-used.When i look at it,it just looks like you remove the bearing and spacer with a normal puller,then press the new bearing and spacer on together? Thanks in advance for any help you can give,Mike

[clive f]

sounds like you need a chat with dnb mike, he had problems with diff bearings.

[dnb]

Recently found that the cause of my leaking output shaft seal is some pitting on the surface of which the seal runs(i think this is a spacer?)
I've had a couple of good used ones arrive and i'd like to replace the bearings as a matter of course.Is the spacer i refer to,which sits adjacent to the bearing,known as a collapsable spacer?If so,what is its colapseable puprose and how do you remove it without damaging it so that it can be re-used.When i look at it,it just looks like you remove the bearing and spacer with a normal puller,then press the new bearing and spacer on together? Thanks in advance for any help you can give,Mike


The output shaft seals should be integral to the outer bearings. (They were removable on mine, but at a guess they couldn't be properly reinstalled.) These bearings need to be sealed BOTH sides, else it will still leak.

The collapsible spacer is on the pinion shaft, and once removed should be thrown away. It is collapsable so that the preload can be set so crownwheel and pinion mesh correctly. You shouldn't need to disturb this to replace the outer output shaft bearings. There are inner bearings too, so you shouldn't need to dismantle the whole diff, or even take the rear cover off.

[The AJP Griff]

dnb said:

The output shaft seals should be integral to the outer bearings. (They were removable on mine, but at a guess they couldn't be properly reinstalled.) These bearings need to be sealed BOTH sides, else it will still leak.

The output shaft seal fits into the diff casing and its inner circumference seals on what i think is called the spacer,located on the output shaft.This is what keeps the oil back in the diff.I think you are refering to the dust seals on the bearing,which come pre-fitted.


ETA-now that i've now re-read your bit about the pinion shaft,Dave.I realise that you dont need to remove it,the two out put shafts have already been removed,which is how Stuart(Forza West) found the pitting which is damaging the oil seals.I've had a chat with Stu today and the spacer does come off with the old bearing as i thought.I've been lucky to find the proper bearings for sensible money so wanted to replace them and the shaft oil seal.
Thanks for the GKN diff manual Fester

Edited by The AJP Griff on Friday 3rd April 18:36

[Uncle Fester]

GKN diff workshop manual

[dnb]

The AJP Griff said:

The output shaft seal fits into the diff casing and its inner circumference seals on what i think is called the spacer,located on the output shaft.This is what keeps the oil back in the diff.I think you are refering to the dust seals on the bearing,which come pre-fitted.

This is exactly it. There is (as far as I remember) no seal as such other than the metal-on-metal contact of the spacer.

Well done for finding the bearings. I failed miserably on that score and got bored with some of the TVR parts supplying community's lack of urgency... And also make sure you can get spacers because they have an annoying habit of distorting when they are removed from the output shaft. Barry made some new ones for mine because it was faster and easier than trying to buy them given everything else that went on.

[TVRBessy]

Hi guys,

I really need some help on this one.... my drivers side output shaft seal was leaking (GKN), on removing the output flange from the diff it would appear that the bearing is 'gravely' (understandably).

@dnb I share your frustration at the cost/ lack of urgency in trying to find a replacement bearing.

Apparently the Simply Bearings one can be used with a 'shim' - does anyone have more details on the 'shim' perhaps dimensions and why it's required?

http://simplybearings.co.uk/shop/advanced_search_r...

@The AJP Griff - even better if you could share your source for the bearings?

PS - My profile would suggest I'm new to PH, but i'm just a dormant member that had to start a new account due to email/ psswd issues :-)

Cheers, Lee

[dnb]

This is stretching my memory a bit... I ended up getting thinner bearings for the output shafts and having shims made to make up the difference from the OE bearings so that the outer face of the bearing sat in the same place.

As an aside, I found the collapsible spacer on the input shaft had collapsed beyond anything useful, meaning it was the source of all the nasty diff noises. I had a solid spacer machined to the correct size and it's never been a problem since, even with my lead booted driving. (When the car works)

[TVRBessy]

I appreciate your response (it's an old thread).

I'm hoping this will help some others also.

Did you by chance have a 2mm shim (shaped like a washer) made up to take the Simply Bearings bearing thickness from 17mm to 19mm?

... and is the collapsible spacer you refer to the one holding that bearing on in the pic below?

I'm hoping this may help others too as I personally couldn't find a picture.

[Sardonicus]

TVRBessy said:

I appreciate your response (it's an old thread).

I'm hoping this will help some others also.

Did you by chance have a 2mm shim (shaped like a washer) made up to take the Simply Bearings bearing thickness from 17mm to 19mm?

... and is the collapsible spacer you refer to the one holding that bearing on in the pic below?

I'm hoping this may help others too as I personally couldn't find a picture.

That spacer you see in shot is just a bearing retainer that is an interference fit on the output shaft also in shot, the collapsible spacer is on the input pinion shaft only

[Pete Mac]

TVRBessy said:

I appreciate your response (it's an old thread).

I'm hoping this will help some others also.

Did you by chance have a 2mm shim (shaped like a washer) made up to take the Simply Bearings bearing thickness from 17mm to 19mm?

... and is the collapsible spacer you refer to the one holding that bearing on in the pic below?

I'm hoping this may help others too as I personally couldn't find a picture.

Lee, I'm very interested in any info you have on this. As part of my 'nut and bolt' rebuild I was planning to rebuild the diff as a matter of course, replacing all bearings and seals. I was planning to source them using the reference numbers on the seals and bearings, however it sounds like this may be more of a problem than it first sounds. Are you saying it is impossible to buy 19mm thick bearings?

I'm also struggling to find a decent rebuild manual, the thread put up in 2009 doesn't seem to exist now. Again any tips? Good luck and any tips much appreciated, particularly on sourcing bearings and seals. Pete

[TVRBessy]

Hi Pete - you can get the seals from Andy @ Clever Trevor, they don't cost much.

Re the bearings I think there are two options;

1) Get the ones from here http://www.wychbearings.co.uk/6207-2rs_fag.html for about £10 each and use a 2mm shim to make them 19mm thick (although these share the same part number they are 17mm and I think we need 19mm @dnb to confirm) - understanding it was like 5 years ago he did this.

My bearings have part number 6207 RSR, the ones at the above link are 6207 2RS, I think the 'special' characteristics of our bearing are denoted by the number 543178 on the outer metal edge.

2) Get the exact same bearing that TVR used, I believe it's a Maserati GKN diff from the bi-turbo and I know John at Grantura Engineering can get them, but they are £80 each.

[Pete Mac]

Much appreciated both, Pete

[spend]

Is this the guide you are referring to?

http://tvr.dspen.com/GKN-Diff/alfieri155-3.htm

[TVRBessy]

Thanks Spend, Lesson Learned here for me is..... if your diff seals are leaking (and only a little bit) the loss of a small amount of oil is not the only consequence. If I had of changed the seal earlier then grit may not have got in and the bearing would not have turned 'gravely'!

[Pete Mac]

spend said:

Is this the guide you are referring to?

http://tvr.dspen.com/GKN-Diff/alfieri155-3.htm

Cracking, that looks exactly it, thanks again, Pete