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MG Midget and Sprite Technical - Rocker cover gasket

I am about to fit a second hand aluminium rocker cover using a cork gasket to my 1275 engine.
Should I use a sealing compound on the gasket to rocker cover surface. -there seems to be a variety of options in the archives, and I wonder what is the current thinking.
Also what toque should I use securing it?

Many thanks,
Nick
J.N. Williams

I use blue Hylomar but I have equal success with grease applied to both sides of the gasket. The torque is very low 4ft lbs
Bob Beaumont

I've only ever used grease so the gasket isn't damaged when removing rocker cover. Just nip up the two bolts. Bit of oil seepage doesn't matter imv.
Bill B

I use Blue Hylomar to attach, and hold in place, the gasket to the rocker cover but nothing between gasket and cylinder head.
Les Robinson

I have a steel rocker cover screwed onto the garage wall. I keep spare cork rocker cover gaskets slid over its outside to maintain their shape. It appears to help when it comes to fitting the gasket. The Old fashioned method of fitting is to apply grease to the mating faces of the gasket when fitting.

Alan Anstead

Many thanks for your help. I've used blue Hylomar to the gasket-rocker cover and a slight smear of grease on the head surface.
Nick
J.N. Williams

I use a cork gasket stuck to the cover with silicone. Just a smear of oil on the underside. Oddly I have an alloy cover that came cheaply from Sussex Classic Car when they closed down, and it has always leaked. I have checked it on a surface plate and can't see anything wrong with it. I tried various thicknesses of washer and still it leaked. So I gave up, it was only a vanity item.
Les Rose

I had loads of issues with leaking rocker gaskets, so decided to blue hylomar the gasket on the bottom and left it dry on the top, then tightened the alloy rocker box down hard, now the gasket is stuck to the head and retains the oil, even if the rocker box comes off - so far has been my most successful and reusable rocker gasket
Malc Gilliver

Les - I have an alloy cover too, but mine's an Ashley GT one. I'd rather have a proper one actually, though I think the alloy ones are quieter.
Nick and Cherry Scoop

Nick
Alloy covers are not quiet if you have roller rockers hammering away like a sewing machine.
Alan Anstead

I bought a set of bright purple 1.5 ratio roller rockers from Nick Veuger - remember him? and had them on my AAN10 Sprite, but they made such a racket and changed the feel of the car so much that I took them off again. I couldn't find any scuff marks on the alloy cover but from the noise I am pretty sure they were having an argument in there! Nick took them back and gave me a nice 1098 engine instead which is now in my Frogeye. 😁
GuyW

This thread was discussed between 02/07/2026 and 11/07/2026

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