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MG Midget and Sprite Technical - Gasket sealant

Just about to refit the bell housing on my Type9 gearbox.
There is a paper gasket between the bell housing and gearbox, should I fit it dry or use Hylomar Blue on both sides of the gasket.
Previously have used Hylomar but just interested in peoples thoughts.
Wouldn’t use it on cork gaskets as in my experience it makes the gasket extrude from the joint.
Can you tell I’m bored!!
Les
Les Robinson

I used blue hylomar on that gasket too.
anamnesis

Longtime fanboy for Blue Hylomar but lately I've been a bit of a convert to black Wellseal.
Good stuff. Tolerant of high temperatures too, and it separates easily next time.
Greybeard

Since that joint isn't containing any oil or other liquid I don't think a sealant is really necessary. Sureky the paper gasket is only there to prevent a bi-metal reaction between the alloy bell housing and the CI gearbox casing.
GuyW

The selector shaft needs to be sealed against any water ingress via the joint between the bell housing and gbox.

anamnesis

Bathed in oil. I think a dry compressed paper gasket is sufficient. There's no pressure forcing water in, just capillary action which the gasket will deal with.
I put mine together dry at that joint. Just be careful tightening the 4 bolts progressively and evenly, the lugs on the gearbox casing can shear.
GuyW

Guess there is no downside to using Hylomar on this gasket.
Guy, I will be careful tightening the bolts, thanks. I have got a manual with the torque settings.
Les Robinson

I've gone off using Hylomar, I know it's supposed to be good, but my stuff of choice now is a spraycan of coppercote, seals great and easy to use---no waste. just spray the gasket, wait 'till it's dry/gone sticky and bolt it up---easy cleanup if it has to come apart.
willy
William Revit

I do remember smearing grease onto paper gaskets, but can't remember the application where that was supposed to be the procedure. Probably not even on Spridgets! Might have been old british motorbikes. Or Austin 7's.
GuyW

A search on Ford forums, reveals plenty of Ford gear boxes had water in them courtesy of not sealing around the selector shaft. It was known in Cortina and Capris etc, and my earlier Consul Capri, that rain water made its way down the back of the engine, and into the box via the paper gasket/selector shaft.

A smear of sealant there does no harm, and has a specific benefit.


anamnesis

A thin smear of Hylomar it is then.
Will put a smear on the gasket prior to fitting to the gearbox and a smear on the bell housing face prior to fitting.
All I need now is the gasket, hopefully coming today.
Les Robinson

My top tip of the day.
If you're stuck for a paper gasket nip down to your local yacht club/LifeBoat station/ship chandlers and cadge an out of date or redundant Admiralty sea chart.
Best gasket paper ever.

(Or message me and I'll send you something from my collection of useless charts that I can't bear to throw away. Just in case...)

Bit off-topic. As you were...
Greybeard

Bit of an odd question, when fitting the starter motor bolts does the nut go on the gearbox side or starter side? Does it matter?
Les Robinson

Been a while since I had mine out. But I think my nuts are gearbox side. I think it only matters for ease of fitting, which is why mine are fitted that way.

I'll have to go and look now though, to see if I'm right. 😂.

Just in time to edit.

Lol. I was wrong. My nuts are engine side; must be easier that way. I can't think of any other reason. 😅

anamnesis

I have now fitted mine with nuts on gearbox side.
I’ve never removed the starter while in the car so not sure which way would be easier.
Anyway, engine is back in the car now.
Les Robinson

Picture is of my exhibition bellhousing.
The lower nut for the starter motor being awkward to get at the bolt hole has been enlarged and a stepped threaded sleeve inserted so that just a bolt is required for the lower starter motor fixing.
Bellhousing showcases one of my roller release bearings for 1275 when using a stock clutch. ‘Quick fit’ clutch slave cylinder with a remote bleed.

Alan Anstead

This thread was discussed between 11/04/2025 and 14/04/2025

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