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MG Midget and Sprite Technical - Clutch area seals advice

I see from the archive there is some info regarding the front gearbox seal. Malcolm asked about this when he was putting his bell housing back on his rebuilt gearbox (Debs was on the same thread giving advice).
So is the seal part of / does the seal fit in the bell housing rather than the gearbox?

Do I need any other parts as well as the seal? (I see there is a 'front cover' in the parts catalogues as well; does this need replacing?).
Does the bell housing to gearbox gasket keep gearbox oil out of the bell housing as well?
Is there a chance the top cover gasket has failed? (There is clean oil all over the box from the front back).

At the moment I am working on the premise that the box has a lip seal as the car mechanicals seem original and its a 78 (January).

Also I may have a rear engine oil seal failure (not so likely as the oil under the car now I fixed the tensioner and associated gaskets seems to be clean). However as I am trying to use just this car as my daily drive and the modern is out at 4.00 am when the wife is working (taxi the wife days when the midget is off the road are killers). I need to keep all possibilities covered. While the clutch is off is it possible to replace the 1500 rear engine crank oil seal without removing the crank?

Now for the other question. I have a P reg 1500 gearbox that is unknown to me (I have no idea how good it is). Is it likely to be OK? And what are the chances it would be better than my rough first gear leaking box?

Just gearing my brain up to speed at the moment as I always need to get an idea of where I am going before I attempt something 'new' so all help appreciated.

Thanks in advance. Cheers, Dave
Dave Squire 1500

Hey Dave,

You only need to worry about the lip seal and not the front cover.

Yes the bellhousing to gearbox gasket seals an oil path.

Also, the lower bell housing bolt has a copper washer, this seals another oil path. Have you had things apart before? Perhaps this is the leak path if you/whoever didn't notice this needed to be a copper sealing washer?

If you are looking to overhaul the other box there are gasket+bearing+seals+synchros kits from Rimmers for about £150. Hit ebay there are kits minus the synchros for 90, or just gasket+seal sets for 15.

The wear parts tend to be the input shaft bearing and the layshaft and its associated bearings. Dunno if the synchros are a particular wear item. I replaced them anyway but the ones I took out looked fine (Still have them if you like!).

Malcolm

M Le Chevalier

And the other bit... the rear crank seal. No you don't need to remove the crank, but you do need to remove the flywheel.

There are also a couple of sump bolts that go upwards into the rear seal housing. And you will need a new rear seal housing gasket. Oh... probably a copper washer or two as well!!

Pic of rear crank seal and housing attached.

If you need any other pictures gimme a shout.

Malcolm.

M Le Chevalier

Dave

I've got three of these gearboxes, 1 in car 2 out, all have scroll seals. I had a problem keeping the oil in the gearbox, I finally tracked it down to oil finding its way out of the breather. The give away was that when I put my hand up the side of the gearbox I could feel oil laying in the trough around the edge of the top cover. I figured the only way it could get there is via the breather.

Eventually the only way I could stop it leaking was to remove the breather and replace it with a pipe that went to a home made catch tank that sits beside the battery.

This may not be your issue but itís easy to check if you can get under the car and put your hand up the side of the gearbox.

Bob
R.A Davis

Hi Malcolm, I haven't had it out and looking at the accumulated road gunk that was all over it when I had the car I think there is a good chance it has never been out. Thanks for all the tips they are very helpful. I will have a good look at the box and see if I can manage to identify the leak based on yours and Bobs info. I want to decide whether I should take it all out, fix the leak, and put it back or have a good look at the other box I have and see if that would be better. I am coming to the conclusion that I probably need to clean the other box up, check it out, and use that anyway as this box has a rather bad noise in first from time to time that I should take time out to address.
Rather relieved that the rear engine oil seal can be sorted without crank out. If this is a problem its a relatively easy low cost fix so good news.

Hi Bob, looked at my spare gearbox and can't find a 'breather'. Looked on the Moss and MGOC sites and can't find one on there either. Are you talking about what looks like a small bolt towards the front edge of the top cover plate?

Thanks both. Most helpful. Dave
Dave Squire 1500

Must be brief, internet locks come on at 2pm (to force us to work!) this site is on the black list! boo!

Pic of gearbox with breather circled.

Malcolm

M Le Chevalier

Thanks Malcolm, that's what I was thinking of.
Dave Squire 1500

Hi Dave,
Someone has mentioned about gearbox oil on top of the gearbox, this is caused by the 2 breather holes in the breather button being aligned across the car, if you align them length ways you don't get the problem.
Also, if the gearbox is coming out, then I would advise you to change the rear mounting bobbins, they are not expensive and impossible to change with the gearbox in place.
Thirdly, there is plenty of scope in the clutch operating arm pivots for wear, well worth changing and will improve the gear change.

http://www.moss-europe.co.uk/Shop/ViewProducts.aspx?PlateIndexID=1320

items 65 and 66,76 and 77, and 62 if you can get them, but you can turn these round, and make sure the go back in the right way up.

If it is any help, my 1500 was first reg in Jan 78 and has the scroll type seal.

HTH
Alan
A Pritchett

Dave,
I forgot to include these:

http://www.moss-europe.co.uk/Shop/ViewProducts.aspx?PlateIndexID=1323

number 18

Alan
A Pritchett

That's interesting Alan; I was expecting it to be lip as I always think of my 78 as a 'late' car. I suppose they could have had a change over / both on the line at some point and it may have been around then.
Thanks for the heads up on the other bits.

Cheers, Dave
Dave Squire 1500

I have a 1975 Midget with gearbox I think is from a Sprite Number stamped is FT9071. It currently has a scroll type seal. Can I change to a lip type seal if I use the lip seal housing in the bell housing? Moss says the input or first motion shafts are different. Someone help Thanks all.
lcl lengel

What engine do you have in your 1975 Midget?
Dave O'Neill 2

This thread was discussed between 11/02/2014 and 04/03/2016

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.