Changing the rocker cover gasket on a BMC 1.5

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SimonA

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Anyone done it?

Mine is leaking oil down the side of the engine so I'm keen to get a new gasket. They are only a couple of pounds to buy but I'm wondering how easy they are to replace.
 
Undo the two bolts on the top of the cover and bingo, off it comes. You usually have to push the gasket into the groove around the cover, a little gasket sealant will probably help too, drop it back on and hopefully problem solved.

Probably only take 15 mins if access to your engine isnt too bad.

Other causes of BMC leaking oil down the side are blocked or ill fitting breather pipes, and tappet side covers leaking, all easy and cheap to fix.
 
Just a little refinement (because I just did this on a BMC car engine)

Completely clean the surface of the cover flange/groove of every scrap of old gasket and wash with meths to remove any old sealant.

Then very carefully coat this surface with Red Hermetite and leave to evaporate for half an hour or so to thicken it from the original runniness - less time needed in hot climates. After this, apply the gasket to the sealant making sure that the goo spreads fully over the face of the gasket. Invert the cover onto a hard flat surface (like a sheet of glass or a smooth hard workbench top) and leave overnight. Work neatly to avoid the Hermetite running down and glueing your gasket to the bench and subsequently your engine!

Following day, you will find the gasket nicely glued to the cover. You should then coat the other face with silicone grease to prevent permanent adhesion to the cylinder head and re-fit the cover with the original socket screws but if the seals on these are perished - another source of leaks - replace them.

All BMC rocker covers are prone to leakage, A, B, or C series but I've found the above method best to address this.

Steve Cronin
 
Re: Just a little refinement (because I just did this on a BMC car engine)

I prefer Blue Hylomar.....it's easier to get off next time. I can't remember seeing hermatite for years.
 
Re: Just a little refinement (because I just did this on a BMC car engine)

Good advice steve, glueing the gasket to the cover with sealant certainly helps get the blighter back on in one piece! Can be fiddly to keep the gasket within its goove.
 
Re: Just a little refinement (because I just did this on a BMC car engine)

Bought a tube of Hylomar once but never got on with it. For cork it won't wet the surface properly.

Anyway, each to his own.

No problem getting Hermetite, it's readily available at most engineering & motor factor outlets. I think i saw it at Halfords the other day too.

Sreve Cronin
 
Re: Just a little refinement (because I just did this on a BMC car eng

I go along with Blue Hylomar. I've built leak-free Mini engines with it, so it must be good. /forums/images/graemlins/cool.gif
 
Re: Just a little refinement (because I just did this on a BMC car eng

I got round the leak problem when I fitted a new gasket by taking the rocker cover off again and smearing the inside vertical face of the cork with grease. I was told about this by someone who learned the hard way that you cannot always get them to seal by over-tightening the bolts. I was also told they very rarely seal properly with the correct torque because of the porosity of the cork.
 
Re: Just a little refinement (because I just did this on a BMC car eng

Red hermetite can wreck an engine if its not used carefully. If its allowed to ooze out inside the engine then bits tend to break off and get into the oilways. I have seen more than one engine badly damaged by oil starvation directly caused by lumps of hermetite blocking the oil sump pick up strainer almost completely. Blue Hylomar doesnt break up the same way. Any sealant needs to be use with care, as if too much gets inside the engine it can cause problems and blockages.
 
Allinson\'s Brown Bread...

...can "wreck an engine" too if you drop great blobs of it into a cylinder. But then you wouldn't, would you?

Didn't you notice that I told the guy to work tidily!

What is it about this site that...

aw forget it!

Steve Cronin
 
Re: Allinson\'s Brown Bread...

Carry on, you were going to say----- "if theres a hair left to split, someone will split it."
Or something like that.
 
Re: Allinson\'s Brown Bread...

Never mind. If it works on Landrover engines I`ll believe all of you
Alex
 
Re: Just a little refinement (because I just did this on a BMC car engine)

Seems unnecessarily complicated. When I had one of these little BMCs I used to smear BOTH sides of the rocker cover gasket with grease. Certainly held it in place and never experienced any leaks. In fact, there are good reasons for not using a hard-setting sealant with any 'soft' gasket
 
I used to have a BMC 1.5 in my first car, an Austin A50, oops! showing my age now! I always used a bit of high melting point grease to seal that gasket.

The trick is to gently tighten down the two bolts evenly and check for a few days after installation and gently tighten the bolts until leakage ceases.

Never had any problem with that.

The car rusted to pieces! Positive earth! What idiot designed that ?!!!


Regards.

Alan.
 
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