Gearbox rear seal S1 2+2

[Paul bow]

Hi.. I was hoping someone could shed some light on a real pain of a problem.
The car a S1 2+2 has been completely rebuilt, engine And box out engine rebuilt, gear box stripped and all that seemed obvious was a new speedo drive shaft, the rear main tail bearing and obviously the rear main seal.
After 1k miles no leaks all perfect, then oh no a few drips of oil on the garage floor.. closer inspection proved it was coming from the tail end of the box, Hoping it was a leak from the speedo drive I removed it fitted a new O ring put it all back .. but yes you guessed still the same.
Took the centre console out looked through the inspection plate and maybe just a tiniest amount looked a little wet.
Anyhow long story short changed the seal put it all back still leaking!!!
So annoying! Any ideas guys, checked the breather pipe that was clear, and the prop shaft flange was as bright as a new pin when inserted in the box, it was rubbed down with 400 grit wet n dry and didn’t even chance spraying it.
Any help
Thanks guys

[Jack the lad]

Hi Paul,
you do not mention if its auto or manual gearbox. The use of 400 grit wet/dry is too severe, I would like to use 1200 only or just a metal polish (Solvol Autosol) or similar. The seal could be a cheap item (China) and out of size tolerance. You need to use a well known branded item only, pay a bit more for a quality item. With it out of the car (proper pain), measure the part of the drive flange that goes into the gearbox, look for a shallow groove where the oil seals "rubs". Also it may be that in the past a previous owner(s) could also have removed metal with 400 grit w&d. The leak could be from the outer edge of the oil seal, refit it with Blue Hylomar sealer.
I use a U/V dye added to the oil, then search for the leak with a U/V lamp, kits are cheap and plentiful. Have you got the correct grade of oil in the box? Hope this helps, cheers John.

[Paul bow]

Thanks John.
Sorry .. it’s a manual, and I’m using redline mt90 oil.

I did finish with a scotch brite (grey) and sealed the seal, but your 100% right when you mention a cheap made in China seal.. this was the second time for me with the same supplier (Sng), I would have paid 10x the price for a jaguar item or a good upgrade but I could not source one anywhere. I would mention I called the supplier and they couldn’t have been more helpful in trying to source another, but did say they hadn’t had any back..
Sng called me to say that an idea maybe to machine down the input flange then sleeve it to bring back to spec, sounds plausible but I think it’s a poor seal of cheap quality, there only £3 !
Do you know where you can obtain another item of perhaps better quality?
Many thanks

[tim wood]

Have you considered the below;
https://www.skf.com/uk/products/industr ... edi-sleeve

[johnetype]

Based on my experience, Redline MTL gets past oil seals much more easily than regular gearbox oil.

[mgcjag]

MTL and MT90....different oils......its suggested on the foum the MTL is good for the Moss box...and MT90 for the later 4 syncro box......Steve

[Paul bow]

Thanks guys..
Yes it’s mt90 fully syn oil.
The sleeve idea looks promising bring it up a few thou, I’ll have to call them Monday, thank you for that.
It’s just not an obvious fix, and prob an accumulation of fine synthetic oil, a cheap oil seal and a slightly worn shaft.
Food for thought, it’s got to be right next time I’d hate to do it 3 times with the same result...
For those that are interested, I managed to do the job without removing the prop shaft or gearbox, I’ll post it if anyone’s interested..
Thanks again guys

[abowie]

A SpeediSleeve is a good idea. I tend to do this routinely.

The seals are just a generic size. Find your local hydraulic and seal supply shop and buy a brand name (SKF, Timken etc) one from them. Ask them if a double lipped seal might be better. They will also sell the SpeediSleeves.

A few pics would be nice; no-one ever believes me that you can do this with the box in

[Paul bow]

Thanks for that Andrew.
With regards to the sleeve is it not possible for the oils to get between the output shaft flange and the said sleeve and thus straight out the end and into the floor...
What actually stops that from happening?
I can see how that sleeve makes a good fit to the seal, but not sure how u going to stop the problem occurring from the sleeve and shaft..
Just googled the speedo sleeve
Just watched the speedo sleeve video..
So that answers all the question above !

I did try to show some pics of removing the seal with box and IRS in but couldn’t upload because the format was to large?? Not sure how to do reduce them either!
So I’ll try n explain how I do it, prob not for the purists but it saved a tone of work..
1 disconnect prop at both ends.
2 remove handbrake cable and disconnect the rear anti roll bar brackets.
3 remove centre consul and arm rest, exposing inspection hole.
4 now this part is the key bit..I made the inspection hole twice as long, this enables once the prop has been moved as far back and over to the side as is possible. Then the front of the prop to rise just a bit more through the inspection hole allowing the flange to pass under the prop.
Obviously once the nut and split pin has been removed
Putting the new seal in is easy as you can work from the top and putting the whole lot back was easier than taking apart.
5. Fabricate a new inspection cover, you now also have great access to the UJ’s at service time.
It was frustrating job at first because getting the nut off was the easy part, even removing the flange of the shaft believing at any minute I was going to drop off, only to realise it’s not going to, you have an inch of thread on the Gbox output shaft you just can’t get it over!!!
But with a little modification that only you will ever know about.. off she comes!!
Hope that might help somebody?
Thanks

[Paul bow]

Thanks everyone who helped out, new on here, much appreciated!
Great work thanks again

[Joes66]

If it was me I would try another seal first
Then if it still leaks find a good used output flange
Joe

[Paul bow]

Thanks joe, don’t forget this is the second one I’ve put in now, with the utmost care as well..
As for buying a new one mine looks absolutely perfect, clearly something is amiss, those speedi sleeves look really good though have you seen them ?

[mgcjag]

Hi Paul...what do you mean "cut the inspection hole larger"....do you mean you cut the top of the tunnel...? The seal can be replaced without cutting.......all from under the car.....Steve

[Paul bow]

Hi Steve, indeed that was what I had to do, make the inspection hole on top of the tunnel twice as long.
I spent a good amount of time shuffling that prop shaft every which way but just could not get that flange off, everything disconnected, handbrake cable removed and the guide in the tunnel bent flat to allow more movement, just couldn’t get that last bit!!!
I suppose looking back maybe tilting the irs may have helped.
Managed to get the nut off easy enough, And get within 1/2 inch of removing the shaft but couldn’t find that extra 1/2 inch of movement anywhere..
Love to know how u did it pal..
Many thanks

[mgcjag]

Remove gearbox rear mount plate.....disconnect propshaft front and rear.....drop rear torsion bar.you may have to remove handbrake cable from the welded loop retainer in rear of tunnel and bend loop...(prop does have a silde spline joint)..you can now get the prop in a position to remove rear gearbox flange .....interior trim all left in place...no cutting of tunnel....Shame you didnt ask here first......Steve

[Paul bow]

Hi Steve exactly that was what I did, I saw it done on a you tube video, however the devil was in the final detail when the guys mentions it is an overdrive box..
I Must be missing a trick here when i done it.
You have yourself done this Steve?
I just couldn’t get the last 10/12mm anywhere..
Yes I wish I’d joined 2 years ago when I started the restoration, would have saved much time and probably money too!
Well it’s all got to come back out so I’ll give it another go from underneath, as long as I know you have done it yourself I know it’s possible!
Thank you
Paul

[mgcjag]

Hi Paul.....you may have caught me out now .....a few years ago now...it was definatly a 2+2 gearbox...they are the same length as 4 syncro with compact A o/d and use the same prop......however i cant remember if it was originally an auto car that has a different tunnel........so i could be totally wrong that it can be done in a standard 2+2...........Check out Rob Beere for a seal......he may have good ones.....Steve

[Paul bow]

Thanks Steve.. yes didn’t even think of Rob, use him a lot really helpful fella.
Well I know that enlarging that inspection hole by another 3” is a cheat, but at least i don’t have to drop that irs out for a 3rd time..
Also you can now grease the UJ’s with ease!
with a new fabricated cover I think it’s a cheap/quick modification worth doing if you have this job on your to do list..

[Paul bow]

Well the jobs all done, I used the speedi sleeve that tim further up on this post gave advice.
I also spoke to ken at Klassic English transmissions who also recommended this product, he also advised that this was almost certainly the problem (output shaft flange wear)
Well I was pleased for the modification to get all this apart again and now being a master at this removal/refit I got the whole job done in a good day.
I mentioned not rating the seals, Ken who would clearly have more idea than me said they are fine, I had a spare new one so used that..
Anyhow I ran it up today on axle stands and pleased to say no leaks!!!
As soon as the weather drys up I’ll take it out for a good 30 mile run but I’ll take the good news For today.
Been a headache, speedi sleeves, never heard of them, cheers Tim , and all for their input.
Nb, I got these from Gosnay engineering, they keep them in stock

[mgcjag]

Great that you got it sorted and opted for the sleeve