M20 blowing rocker gaskets

[E34-520iSE]

OK, so my latest cam-cover gasket has blown within 800 miles. That's the fourth one in 3 years. The latest one blew out nearly an inch of itself at the back of the block near no.6 spark plug. The others blew at the front. What's going on? Is it not possible to have an M20 with no oil leaks? Do we really have to live with the (un)fresh smell of hot oil occasionally? If I fill the engine with up with horse dung will that help seal the gasket?

Cheers,

Shaun M

[Blitzkrieg Bob]

do you have a lot of exhaust gases in the crankcase and valve cover?

The higher pressures could push out the gasket.

or it's just an under torqued valve cover.

[E34-520iSE]

do you have a lot of exhaust gases in the crankcase and valve cover?

The higher pressures could push out the gasket.

or it's just an under torqued valve cover.

Hmm the thing did backfire once, shortly after fitting the head. I wonder if that, combined with under torqued nuts has done it? The previous head had snapped studs, stripped threads here and there, so a poor fitting rocker cover was the obvious symptom. After fitting this new & refreshed E30 head I thought that would be end of the oil leaks..... oh well!

Cheers,

Shaun M

[Blitzkrieg Bob]

Hmm the thing did backfire once, shortly after fitting the head. I wonder if that, combined with under torqued nuts has done it?

Cheers,

Shaun M

My gaskets last forever

[632 Regal]

maybe the cover is warped?

[E34-520iSE]

I never even thought that it could be warped Jeff. As I said before, that cover was on a head that had three missing bolts. I suppose it would have to twist somewhere. I'll clean & paint the E30 rocker cover that was fitted to the 'new' head originally, and see what happens then.

Cheers,

Shaun M

[632 Regal]

the missing bolts rang a loud buzzer in my head, I hate when that happens...gonna go deaf

[Ross]

When you reinstall the new gasket you might want to use an old trick to keep gaskets in place.
Using a sharp punch make a couple rows of dimples in the sealing surface.
The raised metal around the dimples grips the gasket when clamped down.
EDIT Check for excessive blowby also

[E34-520iSE]

Check for excessive blowby also
There's no smoke coming out of the oil filler hole - I checked yesterday just in case. It seems to be running really clean. I thought the oil filler cap was designed to 'vent' excess blowby gasses, or is that just on Fords?

Cheers,

Shaun M

[Ross]

Sounds OK then. Hold your hand over the oil filler with it running, you'll notice if pressure builds up.