Leak: Gasket between head and timing chain cover


(Andrew Waugh) #1

On a SI 4.2 E-Type, it looks like oil is coming out between the bottom of the head and the top of the timing chain cover on the Right hand side BUT:

  1. I can see a bit of paper gasket (about 0.75mm thick) sticking out by the front corner - Is there an additional paper gasket in there, or should it just be head gasket material.

  2. If leave it overnight it forms a spot about 15cm in dia, if we raise the front wheels by about 20 cm and leave it overnight then it does not drip.

Power washed the engine yesterday, hopefully the source will be a bit clearer on Monday.

A bit of weeping, sure fair enough, but this much oil when the car is standing, cold - even after a few days says to me that the leak should be down lower.

The bonnet is off, do taking the front cover off without the head is no big deal, I’d rather leave the head on, as the car runs fine.

Opinions? Was the block decked with the timing cover off, and Bubba trimmed the head gasket so he could fit thinner (paper) gaskets in the problem area?


(PhilW) #2

2 of the 4 front head studs need copper washers to seal as oil can sometimes follow down the stud - it’s open to oil on the top. I can’t remember if it’s the front or rear studs. An easy check and fix with sealer. If on a re-build engine, some machine shops forget to bolt on the timing cover when they deck (grind flat) the top of the block and the cover might be higher than the block. The original head gaskets were a paper composite and if it’s showing on the side it might have had the timing cover removed with the head in place to do the chains and a little of the paper was displaced. It’s easy to check if the head was decked. The factory didn’t make the entire head surface flat. They left little nubs on the outside edge. A modern head deck makes the entire surface flat and the original raised nubs are cut flat with the entire surface.

Phil.


(Andrew Waugh) #3

Even a week after the last time the engine was run?


(PhilW) #4

With the covers off, you can see the coarse tapped hole and there’s always a small puddle of oil inside as the stud threads are shorter than the hole length. Double nut the stud to extract it and a bit of oil will follow.

Phil.


(JAMES FAIRMAN) #5

I once had a drip like that.

When I attacked the front studs with a half inch spanner and ratchet, half of them were loose! After a bit of tightening the oil leak went away.