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MG Midget and Sprite Technical - Cork seals for sump

Went to Moss yesterday to pick up the sump gskt and the 2 cork seals but they only had one cork seal in stock. The front and rear cork seal are different part numbers because they are different lengths. So I bought a bottom end gskt set and both seals supplied in the kit are the same. It was suggested I cut the oversize one down to size.
Anybody know what the sizes for the cork seals should be ?

Thanks roy
R Mcknight

fit the seal 1st Roy then cut to size, I leave a couple of mm proud as this will reduce and have a nice tight fit when finished.
Rob Newton

what Rob said is spot-on. I think this is how it's described in the manual too.
David Smith

Yes I agree although I leave 3mm to ensure a good seal. I also coat the seal in hylomar where it sits in the sump and around the main cap.
Bob Beaumont

And I agree with Bob

3mm and hylomarised all round
bill l

which hylomar do you use blue, red, original, XXXB ?
Nigel Atkins

I use blue hylomar.
Dave O'Neill 2

I have always used the Blue coloured variety. i wasn't aware there were any other varieties.....
Bob Beaumont

Dont use RTV in place of hylmar... its not the same stuff

Just a suggestion of something ive found very useful... dont use the gaskets in your bottom end kit,

Buy a sheet of gasket material and use the new gasket set as templetes, ... the reason I do this, is getting these gaskets at the usual suspects (auto zone, oriellys, ect) is not very doable anymore and it takes a week for reg delivery or ungodly expensive over nighted...this way you always have the right gasket... now if there is a place 5 miles away that sells.the needed.gsskets... then screw this comment... haha

Something else I do with the sump gaskets that works really well... learned from a local dirt track racer, RTV one side of the gasket to the sump pan for a permant seal, on the opposite side aka the mating side of the gasket coat a good librial amount of white lithium grease...not the spray on but the goopy grease in a can and bolt togather and retorque in the sump screws in 50 miles or so... the white lithium will seal up and shrink down a bit to fill most voids, but its easy to remove the pan with a minor thump of a rubber mallet thus making the gasket completely reuseable ...just apply another coat of white lithium grease and its ready to go agian and agian.and.agian...and.it never leaks unless you forget to retorqe after reinstalling

I do the same thing with the valve cover ive had that valve.cover.off and on 1000 times overbthe past 6 years and still the same cork gasket

Prop
Prop and the Blackhole Midget

Dont use RTV in place of hylmar... its not the same stuff

Just a suggestion of something ive found very useful... dont use the gaskets in your bottom end kit,

Buy a sheet of gasket material and use the new gasket set as templetes, ... the reason I do this, is getting these gaskets at the usual suspects (auto zone, oriellys, ect) is not very doable anymore and it takes a week for reg delivery or ungodly expensive over nighted...this way you always have the right gasket... now if there is a place 5 miles away that sells.the needed.gsskets... then screw this comment... haha

Something else I do with the sump gaskets that works really well... learned from a local dirt track racer, RTV one side of the gasket to the sump pan for a permant seal, on the mating side of the gasket coat a good librial amount of white lithium grease...not the spray on but the goopy grease in a can and bolt togather and retorque in 50 miles or so... the white lithium with seal up and shrink down a bit to fill most voids, but its easy to remove the pan thus making the gasket completely reuseable ...just apply another coat of white lithium grease and its ready to go agian and agian.and.agian...and.it never leaks unless you forget to retorqe after reinstalling

I do the same thing with the valve cover ive had that valve.cover.off and on 1000 times overbthe past 6 years and still the same cork gasket

Prop
Prop and the Blackhole Midget

I am still stuck on this problem and need to fit the sump so any thoughts on this?

The 2 cork seals I have are 9mm x 4mm in cross section. The groove in the sump is 5mm across.

So what way round are you meant to fit the cork seal into the sump groove?

I find it impossible to squeeze a 9mm seal into the 5mm groove, and if I turn the seal on edge it just too loose surely this cannot be correct.

Either I am being a complete idiot or is it possible the gasket set has got the wrong seals?

Anybody got a spare 1275 cork seal that they can measure the profile please.

All the workshop manuals I have none show sump and seal fitment
.

HELP , Thanks Roy
R Mcknight

Roy,
to save me looking in three different places which cork seals, the straight or the semi-circle

on my engine the back seal is a black plastic thing and front cork but I think I could fit cork at both ends (not sure mind)
Nigel Atkins

Roy

The cork seal is a little thinner than the slot in the sump. When you bolt it up the cork is squashed and expands into the slot in the sump. You still needs to leave the ends slightly proud. What you have is normal.
Bob Beaumont

Roy,
even the much overrated Haynes mentions the sump seals, I know because I followed it's instruction before and still had leaks 1980 Haynes, section 41, page 44 and 1974 Haynes (that doesn't cover the 1973 cars fully let alone 1974) page 37

I can't be bothered to look at the factory Workshop Manual as it's on a very clonky DVD but will if you want me to

1974 Haynes says to leave 1/16th of an inch (1.6mm approx)

whereas 1980 Haynes has it as "After removing the old seals fit the new ones making sure that they bed well down in the housings and, if necessary, trim off any surplus protruding above the sump flange gasket lever" and has a photo above text
Nigel Atkins

Hi Nigel . The cork seals I have are straight but when fitted take on a semi circle profile . Yes when genuine stuff was available I think the cork seal came already shaped and sized, then it was replaced by plasticy seals.
Bob , so you fit the seals edge on and they expand to the correct width when bolted down. That makes a lot of sense. The fact they are so loose is whats thrown me. Fitting them edge on and they constantly try to straighten out and fall out of the groove.
I have ordered another gskt kit and will see if the corks seals are the same in that.
R Mcknight

I never remember them being that loose in the grooves.
It must make it very difficult to fit the sump, particularly if the engine is upside-down.

What make is your gasket kit? I always used Payen, which I'm pretty sure were a good fit.

At one point, I did buy some pre-shaped seals from Rover/Unipart, but one end was cork and the other rubber/plastic.
Dave O'Neill 2

Roy,
(note, all below refers to 1275cc engine)

the eight straight cork seals I have all appear to be about the same size
10mm wide
5.5-6mm deep
156mm long

the preformed semi-circle cork seal is -
9mm wide
5mm deep

the rubber type semi-circle seal is -
9mm wide
about 5.5mm deep
(and is longer than the semi-circle cork)


semi-circle cork seal (front) -
MGOC Spares part number - LBZ10005
Sussex Classic Parts number - CAM6270

Moss Europe - rubber type! - TAM1171


semi-circle rubber seal (rear) -
MGOC Spares part number - TAM1089
Sussex Classic Parts number - CAM6271
Moss Europe part number - TAM1089

so always clear as mud - I wonder if we'd be better off fitting the straight cork seals and leaving 1.6mm-3mm above sump flange gasket
Nigel Atkins

Peter May sells a sump gasket set with rubber seals.
Chris Hasluck

Nigel , That would explain a lot my cork seals are 4mm wide so would be loose fitting in the groove . Will wait and see when my new gskt set arrives and that will confirm if they are Duff parts.
Dave the sump gskt set was from Moss and its no name, and the engine is upside down so you can see the problem with the seal dropping out of place.
Chris , last resort will be Peter May gskt set , should have been my first, although the rubber seals would not be my first choice. Ideally would like some pre formed semi circular cork gskt but cant seem to find any. Anybody know a stockist.

Thanks Guys
R Mcknight

Roy,
if you want I could post you 2, 4, or 6 straight cork seals!

as for semi-circle cork seals, from my previous post -

semi-circle cork seal (front) -
MGOC Spares part number - LBZ10005
Sussex Classic Parts number - CAM6270

would these also fit the rear as after all the straight cork seals are both the same size

not that I want to promote Toss or some of their 'er' management they also sell the front and rear rubber seals as does Brown & Gammons
Nigel Atkins

I put the rubber seals in the car we are finishing, and the engine is not leaking oil anywhere. really, really, we have done a number of runs and the garage floor is clean, as is the underside of the car. And for the sceptics, yes, it is showing oil on the dipstick and oil pressure on the gauge!
dominic clancy

Dominic,
I'm glad to hear that as I've just ordered the other rubber seal to the one I've already got

did you also use blue Hylomar on the rubber end seals and the paper gaskets?

my engine didn't leak until I removed the sump, I can't remember what seals were originally in it but I've changed the seals a couple of times since and still leaks
Nigel Atkins

Finally got to the bottom of the problem. The cheaper of 2 different option sump gasket sets offered by Mo** has undersize cork seals . They are too thin . Bought another gasket set from a different dealer and the corks are wider. Problem solved .

Many thanks for all your help .. Roy
R Mcknight

This thread was discussed between 17/07/2014 and 11/08/2014

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