Head oil leak

Post by **winger300** » Sun Sep 16, 2007 11:12 pm

I've started to notice some oil around the top of the bell housing where the engine is bolted. It's certainly not coming from the rocker cover gasket as that part of the head is clean.

It looks like its coming from between the engine block and cylinder head, on the rear corner (Dizzy side, where the heater tap is fitted).

When the engine is running it doesn't appear to be leaking, but after an hour of driving, there is a smear of oil down the bell housing and engine block.

Sound like a blown Head gasket? There's no oil in the water, or mayonaise in the rocker cover, what's the deal?

Post by **MoggyTech** » Mon Sep 17, 2007 1:01 am

Fairly unusual to get an oil leak from the head gasket at the rear. They normaly weep a little at the front right hand corner just above the bypass hose location.

You could check the cyl head nuts torque.

Is the head gasket the multi layer 'Payne' type with a copper top?

You could do a compression test to be on the safe side. If #4 reads ok, I would suspect the leak (if tiny) might just be a bit of seepage.

No big deal to replace the gasket, 40 minutes on a good day

Post by **winger300** » Mon Sep 17, 2007 9:18 am

No. 2,3,4 was reading 180psi when I checked last week, and No. 1 was slightly higher than the rest.

Post by **bmcecosse** » Mon Sep 17, 2007 9:27 am

Very high pressures for a standard engine ! If you have increased the CR then the head nut torque should also have been increased to match. With the standard studs you can safely go up to 44 ftlbs (put thick washers under the nuts) - with the later Y studs - 50 ftlbs is ok. I suspect oil is leaking along - I have had this on high comp Mini engines - get a spare gasket in stock just in case.