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MG Midget and Sprite Technical - Engine oil leak front cover

Hi Guys I just purchased a 61 midget to go with my YB and notice a decent oil leak from the front of the engine. It leaks even when parked up cold so needs addressed.
I would like to have all possible gaskets on hand before I start so any advice plus what tools might I need, puller etc?

Thanks
K Weeds

You will need a timing cover gasket and the front cover oil seal. While its off it may be worth replacing the timing chain and rubbers tensioners and check the condition of the water pump. You will also need a front pulley nut tab washer.

You have to remove the radiator and front pulley. The radiator is held by 4 1/4" bolts (7/16af spanner size)
They can be a challenge to remove, soak them liberally with Plus Gas or other penetrating fluid. (not WD40!).
The lower radiator hose is also a challenge to get to and remove.

Once the radiator is out of the way you can get to the
front pulley. This can be tight and access is limited by the cross member. It may be necessary to lift the front of the engine so you can get a socket on the pulley nut. To do this you will have to release the front engine mountings. Put a trolley jack or similar under the sump (with a wooden block)to lift. Only raise it enough to get to the nut. Ideally remove it with an air gun or similar.
Once off the pulley should just pull off. Remove the bolts around the timing cover and remove it.

When replacing the cover with the new oil seal, fit the cover and then the pulley temporarily so the oil seal is centred on the pulley before replacing the securing bolts.
Bob Beaumont

Very neatly described Bob!☺
Jeremy MkIII

The chances are it is the pulley seal that has failed. As Bob explains it isn't too dificult to replace this and the cover gasket. But check the stub on the pulley that the lip seal runs on. There is often a wear groove in this which prevents the new seal working properly. Another problem can be a crack in the stub under the key way. If there is wear you can get a machine shop to cean up the surface in a lathe. An original seal won't be of use but I managed to buy a suitably sized metric one from a bearing supplier. If you don't have a lathe or a friendly machine shop a new pulley is about £70. It is also important to check the flange on the cover for flatness. If the bolts have been over tightened in the past there may be distortion. This easilly be corrected whith a hammer and a flat surface.

Just as an after thaught check the sump at the front. Originally there was an asbestos seal here which has been superceeded with a composite rubber one. This is a known leak point and oil will appear to be dripping from the front cover. Again the sump gaskets and seals can be changed without removing the engine but if you don't have a car lift you will be spending time on your back with oil dripping into your face! Lifting the sump as you replace the bolts can be tricky an a couple of temporary, long studs helps with alignment

Good luck


Jan T

Jan T
J Targosz

A speedy sleeve will rectify the wear groove if need be, instead of a different size seal. Easy fit and not too expensive. I've done it to the rear seal on my ford engine.

Otherwise, can you buy a new crank pully?
anamnesis

There's an even simpler solution if the wear groove is smooth.

Increase the pressure of the seal, by increasing the spring tension, by shortening the coil spring.

Remove the coil spring from the new seal. Find the joint. Untwist the ends (anticlock wise probably, but maybe clock). Clip 5/6 coils off. Twist ends together again. Refit to seal.

anamnesis

Being a Mk1, if it has the original 948cc engine, the oil seal will probably be of the felt variety.
Dave O'Neill 2

At least the felt ones are much less prone to wearing a groove in the pulley stub.
GuyW

Yes it is still the 948cc.
Thanks so much for the feedback guys, very helpful.

Kevin
K Weeds

If it's leaking when 'parked up cold' it'd be more likely to be the timing cover gasket leaking ,letting the welled up oil in the bottom of the cover drain out through the leakhole.
A good washdown and a short run should highlight where the oil is coming from-
William Revit

I think I have that problem Willy. Been meaning to do as you suggest to mine. I'll wait for a nice warm spring day.😁
anamnesis

I usually put a socket on the crank pulley bolt, with a long extension braced against the damper, and hit the starter. Comes off a treat. Of course, doing it up again is another matter....

If you are really unlucky the leak might be from behind the front plate, but that's still removable without taking the lump out. So make sure you know exactly where the leak is.

These front plates strip their threads easily, when they get to this age, which is another cause of leaks. I have a Helicoil kit but it doesn't work for such thin metal, so I had to make steel inserts on the lathe, with new threads in them.
Les Rose

Thanks again guys, good info
K Weeds

Another possible is that the timing cover has been bolted up without centering it to the crank-
If you have the cover off , fit your seal to the cover and fit the gasket/cover to the plate but leave it loose enough so that it can move about, push the pulley home, this will centre the seal/cover up on the pulley then while being carefull not to push the cover off centre, tighten the bolts up securing the cover and it should run nice and central----and hopefully dry
William Revit

This thread was discussed between 23/02/2023 and 01/03/2023

MG Midget and Sprite Technical index

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