Hello all my first post on the site. I have a very hard to see oil leak and i don't know what it could possibly be from. It coming from exactly in the center of the engine on the very back. Below the cam/valve cover....even with where the Trans bolts up to. There are two oil lines running across the back of the motor from one side to the other....oil is coming from right below those, in the center. Nearly impossible to see.

It runs down both sides. But more on the passanger side...right on to the exhaust. What a lovely sight and smell.

 

Also....already replaced valve cover gasket, grommets and both half moons.

 

Also....already replaced valve cover gasket, grommets and both half moons.

 

Have you eliminated the possibility the oil might be coming from those oil feed pipes themselves? They use banjo fittings with simple copper washers to seal 'em.

The only other thing I can think of, since you've replaced the cam cover gaskets and half-moon seals, would be the head gasket

Cheers
DD

 

There is also a plate that is held on by six bolts. But i can't tell if us leading from the bottom of that. What is that piece called?

If it is the lower head gasket...and I'll need to partially take apart the top portion of the motor. I may as well replace all gaskets while I'm in there.

Also didn't not mention earlier... I noticed the leak after i switched over from 5w 30 to 10w 30. I'm now using 20w 50 with a gasket sealer you add to your oil...forget the name of it........doormans rear main seal....our something like that...(currently at work)

 

That plate blocks off a coolant passage, so it's out of the picture.

One tip on general principles....might or might not help in your case.

Make sure your breather screen and pipe are clean. If clogged, excessive crankcase pressure can develop and actually force oil past elderly seals and gaskets. I've reduced some major oil leaks reduced to "tolerable" status simply by cleaning the breather.

Unbolt and remove the round breather cover (at the very front of the cylinder head) and remove the screen that fits behind it. Let the screen soak in solvent or gasoline and clean with a brush. Remove and clean the breather pipe as well.

Might wanna order new gaskets for the cover first.

Cheers
DD

 

Just making sure..you're talking about the air intake, right? If so..already done all that. Since were on the subject of pressure....i do have a cel for the heated o2 sensor.

 

CEL? Check Engine Light? On a Ser III XJ6?

Before going any further let's clarify what car you have. A Series I-II-III does not even *have* a check engine light.

Cheers
DD

 

Thank you....i don't know what model i have....i was looking at all the different ones, even the sub models....here's what i know i have

Made in 1/93 England...xj40 body has the aj6 4.0 engine
Rear emblem says xj6 burke. Has alloy wheels and no trays on the back of the front seats..and no pop out lights in the very back corners. All emblems and the cat on the hood is chrome.

 

You belong in the "XJ40" section

Disregard my previous remarks....


Cheers
DD

 

Same engine tho right?

 

Different engine. The series 3 xj6 and all earlier XJ saloons discussed here had the XK6 six cylinder engine. Your 93 XJ40 has an AJ6 engine. Still a twin overhead cam straight six but fundamentally different in engine architecture, combustion chamber and head design. The gents on the XJ40 site will know more about it.