I just had a major oil leak in the oil sump fixed. The mechanic dropped the steering, sump, replaced gaskets, seals, changed bushings and other worn parts that one might find on a 32 yr old series 2 XJL. The oil leak was an old problem that I decided to have fixed. All was well, I was very happy with the repairs. My mechanic even replaced a clogged injector,cam cover gaskets and spark plugs my old 78 had not run so well in a while. About three weeks later as my wife and I sipped on a morning cup of coffee in the kitchen she detected a petrol smell. I rushed out to our attached garage to find petrol all over the floor. That was pretty scary. The hose between the change valve and the fuel pump in the trunk had sprung a serious leak. I fixed that and carefully got the spilled gas from the floor, a lot of the gas was soaked up by the cardboard that I had under the car when it had the oil leak.
Well I decided that I would change the rest of the fuel hoses after which I found that the fuel pump had failed. I put a pump on yesterday, got everything back together, test drove it a short distance, man I was smiling she was finally running good.
I just came from the garage where I started it up with a smile on my face all along saying that's the way it should be. I notice an unusal amount of steam in my exaust, I shut it down, check the oil to find that dreaded milky condition. Oh no--What in the world could cause this other than the head gasket and why? Do you think that the car back firing while I was trying to start it with the old fuel pump on the car may have blown the head gasket?.
Is there a Jaguar mechanic in Southern Maryland that can help me?
The mechanic that fixed the leak said that he would not be able to get to it for a while.
There was a time that I would have jumped right in and started pulling it apart, but not now.

Help

Oledude

 

You may want to give these guys a call:



7718 Lee Highway
Falls Church, VA 22042-7734

Get Directions
(703) 560-6975

They are in VA though.

 

Sounds like a head-off job to me, but there is another avenue for water to get into the oil.

The front timing cover is made of aluminium alloy, and covers the timing chain and also forms the chamber for the water pump and a passage for the water (or coolant) into the block. Over the years the wall of this passage can corrode away until water can leak out into the chain chamber, and hence into the oil. I have actually seen one almost corroded through, so I assume it can go all the way and leak. Also, of course, the timing cover gasket itself could leak as well at this point.

 

Thank you much for that info, I will pull the spark plugs to see if there is anything unusual about their appearence. Is there a test other than the disassembly of the timing cover to diagnose a potential problem with it? I have talked to a couple of shops about the repairs, we talked about the head R&R as well as some other related service.

This is a surprise, the car has not overheated in the past 31 years, I have been pretty good with my PM like oil, anti-freeze and the like. I can't imagine what caused this. Very puzzled I am....I don't think that the timing cover was disturbed when the sump gasket was changed.

 

I found when I had HG failure between cylinder and waterjacket, (the normal failure mode), that the oil remained perfectly OK. There are a couple of oil drains at the back of the engine, (opposite end to timing chains). I suppose the gasket could fail between the coolant passages and one or both of these drain passages.

As regards the cam chain cover, it is just a matter of time, plus previous owners not keeping the coolant up to strength with anti-freeze. The corrosion inhibitors in the anti-freeze prevent, or at least slow down the aluminium from corroding. 32 years is plenty of time for corrosion to work its way through. As a matter of interest, the wall thickness for the coolant passage is about 3/16" but can be less, as it is not a particularly precise casting.

 

If the cause of this situation turns out to be the timing chain cover the sump R&R is necessary and the money spent on the orig repair will have to be spent again. I think this problem is more than I can handle myself, I will be turning it over to a pro. I will keep you posted.

Thanks a bunch

Oledude
1978 XJ6L

 

i recommend a change in coolant type, waterless coolant does not corrode any internal parts.

something like EVANS waterless coolant , has been in one of my cars for 11yrs, absolutly no corrosion, drained a cup out and still color of beer, yellow, just poured it back in.

a good thing about it ,it dont boil and cause hot spots, and soften gaskets etc.
plus lubes water pump seals, all around an excellant product.

and NO im not a sales person.

 

I've always appreciated the good points about that EVANS product. I have never tried it, but was always intrigued. I think it is a bit expensive at first, but sounds like it has definitely paid off. Not having to worry about coolant flushes, not having to dump coolant when changed, engine protection, maybe someday I will try it on a long-term car.

 

Oledude

If you do find you need a new timing cover, don't forget to have it checked on your existing block ,because the top face may be proud or sunk. In a lot of cases, the block witht he new cover bolted on will have to be faced off to make a flat face for the head to bolt onto. The blocks were faced off with these covers in place, because the front of the head bolts down onto the cover using 4 5/16 studs and nuts.

I am trying to think of other potential paths for water into the engine oil but so far cannot think of any more, maybe Doug knows of something.