My nice clean engine has two oil leaks. One, near the distributor, I fear is a head gasket. The other, quite minor, is just annoying to see. Is there supposed to be a grommet or gasket of some sort around the valve cover bolt? Or is it the hose that's leaking? I suppose I'll just clean it off and keep an eye on it to determine which it is. Input is appreciated.

 

My 88 had both of those leaks.

After a good cleaning of the crankcase vent hose and small orifice which provides vaccuum to the crankcase at idle, both leaks stopped. The small orifice, which is fed by the small hose off the main one, was totally plugged, took a good bit of carb cleaner to open it up.

 

An updated cylinder head gasket will fix the leak near the distributor.

Most people don't replace the 7 washers (EBC1294) when they replace the cam cover gaskets. They crush/crack and leak oil when they get old.

Get a set of sealing washers for the fasteners!!!!

bob gauff

 

I read somewhere the head gasket is notorious in these cars for leaking in that corner. I had a leak there which turned out to be the timing chain tensioner. I also replaced the distributor o-rings as I think it had a slow leak as well.

The best way to find the leak is get some good cleaner(I use gun cleaner) and clean up the whole area from top down: valve cover, tensioner, head, distributor; untill it is dirt and oil free. Then start the car and carefully watch where the oil is comming from. Hard to see under the tensioner and thus it may appear to be the head gasket. Get a mirror to differentiate between the two.

If it is coming from neither check the distributor it may be your culprit.

 

I'll clean it all up with some carb cleaner and see if I can spot the leak, thanks.

 

First of all, I wish Muleears luck in fixing his leak.

I, too, have an oil leak, that is driving me crazy. It's on the lower, left side of the engine and I can't find where it's coming from! It's dripping off of the crossmember beneath the engine and although I have jacked the car up and crawled under with a drop light, I can't see where it's leaking. A co-worker who has a '93 XJ6 said he had a similar experience and it turned out to be the oil pan gasket, but how do you tell? There are so many tubes and hoses around the engine that I can't get a clear view. Any thoughts as to what it might be would be appreciated.

 

Here is some info for oil leaks from the 4.0 engine.

bob gauff

 

Left side of the engine has the oil cooler hoses comming from the filter to the oil cooler. The gasket behind the oil filter is currently leaking on mine. Jaguar recomends you buy the oil cooler bypass kit and eliminate the oil cooler all together to eliminate chance for leaks. So check up in that area. Start from the top down and sometimes it is useful for me to put a quart or 2 of clean oil in so I can see acontrast when it is leaking out.

 

The X300 4.0 normally aspirated (And maybe the 1994MY XJ40) did not have an oil cooler but had a 'U' shaped aluminum casting with steel barrels and 'O'rings. You can buy the parts to eliminate the cooler and lines but you will still have the cooler adapter (EBC8168).

The cooler bypass pipe (EBC4124), 2 Steel connectors (EBC4244) and 4 'O'rings (CAC5118) can be installed if the cooler lines are leaking and you don't want to replace them.

The oil filter mount flange can be installed directly to the engine (with short bolts) but you will lose the bypass valve feature in the cooler adapter.

I don't remember any gaskets used in the assembly so I think sealant was used.

bob gauff