Catastrophic Oil Leak
 

Hello Jaguar brethren,

Happy to say I just bought my first Jaguar, a 1997 XK8 convertible. Chagrined to say that within a week of owning it, the oil pressure light came on while driving-bad news bears! I checked the dipstick and it was bone dry. I emptied a 5Q bottle into the filler and went straight home (2 mi), though the light came back on as I pulled back into the garage. Dipstick was bone dry again, and I had left a trail of oil drippings behind me the whole way!

I pop the hood, and there is oil all over the engine bay--so much that it might be hard to find the source. I figured that's a good thing--rather it be leaking than burning. But I am hoping someone here can help me diagnose what gaskets/etc I need to replace to stop this catastrophic leak.

Additional info: I put a little more oil in it after it cooled down out of curiosity, and the filler cap was loose. Maybe I didn't tighten it all the way, or is it possible back pressure unscrewed it? After I put more in, it continued to leak more oil, with the puddle on the ground centered under the bellhousing, though it seems that's just where gravity took the oil from a leak higher up. Valve cover gaskets look pretty grimy on both sides but especially the driver's side. I plan to replace them and look at the secondary tensioners while I'm at it. But I am concerned about the volume of oil that is leaking--this thing is like a sieve at this point. Could the valve covers have that serious of a leak, or could it be somewhere else?

Note that the whole oil pan was very oily too, including the part above the gasket.

I'd appreciate any ideas on things to check/places to start.

Thank you,
Andy

Is your car equipped with an oil cooler ? Blown oil cooler lines account for many engine disasters .


Z

I would start with the valve covers then clean the engine. Be informed that the 2 knock sensors do like water so when cleaning stay away from them.

Gus
JagRepair.com - Jaguar Repair Information Resource

I see a round heatsink with a bunch of fins in the very front behind the grille, but I think this is for power steering fluid.

I do not see any oil cooler, but I could be missing something. Did all AJ26 have one?

You shouldn't have a cooler. My guess is either the rear main bearing seal or the oil gallery plug just above it came out.

But if the oil is all over the engine, maybe the oil filter is loose.

Thanks for the responses, folks. Damn, no luck on the oil filter. Rear main seal sounds like a huge job. Is there any way to check if it is the oil galley plug without dropping the whole trans?

I'd like to add that there is also oil in the front of the engine bay too. Could that just be a coincidence (maybe a symptom of blow-by creating pressure throughout?)? There were no noticeable leaks when I test drove my jag, or in the first couple days of ownership. When I started engine with my hand over the oil filler opening, I didn't feel any kind of pressure.

It's such a mess that it will be hard to identify the source unless you clean up all the oil first. But don't try using a pressure washer clean an tape the coil covers so you don't short the coils. The coil cover gaskets are probably shot. When you do start the engine again, open the oil filler cap and s]ee if air is being drawn in or out. There should be a vacuum and the engine should start running rough.

reading thru old posts on this forum, it seems "some" XK8's did have an oil cooler, that some insist was factory installed. The criteria for having one is very murky. But agreed, essentially most 8's did not not one.

^^^^^^^^ +1 A missing oil galley plug might be the best case scenario here.......

Z

Big Oil Mess - you need to know where it's leaking
 

Gumbo,

Sorry to hear that you've had such a rough start to your XK8 experience with a really bad oil leak. In the Stickies threads, there is the Jaguar Engine Course for the AJ-V8 engine in your car.

https://www.jaguarforums.com/forum/x...ts-data-29800/

This is a good start to try and find possibilities where your bad leak is from. Of particular interest is the section starting Page 50 of 174 showing the plugs described above, which are present in both the front and rear of the engine block. Excerpts below. (Please note that the engine diagrams are upside down).

https://cimg0.ibsrv.net/gimg/www.jag...5aaeb3390a.jpg

https://cimg1.ibsrv.net/gimg/www.jag...fc7895ce80.jpg


As advised above, clean the engine as best you can and then check what you can see - the usual list - oil cap tightness, oil filter, sump drain plug, integrity of the sump pan, camcover gaskets, front crank, front timing cover, VVT solenoids etc. However the scale of your problem does point to integral cracks, and/or main seals and plugs.

https://cimg4.ibsrv.net/gimg/www.jag...aa7733dc4c.jpg


Unfortunately, if you have a bad leak at the rear crankshaft oil seal, there is no way to fix a problem at the rear of the block without pulling the engine out and apart.

https://cimg5.ibsrv.net/gimg/www.jag...81b66c7d6f.jpg
Good luck and let us know how you get on.

The PO of my car ran up on a side walk and smashed the oil cooler, dumped all the oil on startup. Yes my 03 has a factory oil cooler.

Yes, you'll need to do some cleaning to figure out where the leaks are.

Remember the service position for the hood that you'll find instructions for around the forums. Opening the hood higher will give you much more access for investigating the front of the engine.

I bet you have the same I did, with a few leaks dirtying up the front of the engine plus a massive leak from the rear main seal. Like yours, my car dumped basically its entire load of oil in a few miles once the rear main seal went from a dribble to a complete failure. Fortunately it was less than a grand to have an AAMCO here in south east Virginia drop the transmission, replace the seal, and reinstall.

I still have a leaky front timing cover gasket, so there's oil on the surface of the oil pan, but I can live with that for now.

There is a plastic inspection plug at the bottom of the bell housing that you can remove to see how much oil may or may not be leaking from the rear main seal.