Anyone have any idea if the oil pump on the 98 jag 4.0 v8 is the same as on the Lincoln ls? Does anyone know of any precautions I should take when doing the change, or have any tips?

Additionally,
What about the pickup tube?
The oil pan?
the serpentine belt?
head gaskets?
and for the hell of it, the water pump.

 

I assume by your question that you decided you had a blown head gasket (?).

Your '98 is the AJ26 engine, the Lincoln is a modified AJ27. This may take some research but would become a valuable addition to our collective knowledge base.

 

Do you intend to replace the head gaskets on this engine? Has it ever been overheated?

 

Yes, and Yes.

 

Sigh, I just want to drive my car

 

Speaking from personal, professional experience I haven't seen many Jaguar v8 engines recover from overheating if taken to the point of blowing head gaskets. The problem I normally run into is when removing the head bolts pretty much all the threads come out of the block with the bolts. Attempts to helicoil prove futile due to the depth of the threads in the block. The actual threaded portion of the block doesn't begin for at least 8mm below the deck height and the threads are VERY deep requiring special order helicoil inserts. The couple of attempts that have actually left the shop(several others the techs cried "mercy" and changed their diagnosis to "engine replacement") were back within 6 months with the heads blown off again. I think what happens is that when the engine is overheated to a high enough temperature to blow the gaskets, the gaskets blow because the stress pulls the threads from the block. The only thing left holding the bolts in is friction.

On the other hand you don't have anything to lose except time if you are doing this yourself. Try to remove the head bolts and see how it goes. If any come out with the threads from the block I would call it a deal breaker.

I'm not trying to burst your bubble, just trying to avoid a lot of money spent on a repair that may not last long enough to pull out of the shop.

 

Thank you for that insight. I have never encountered that kind of issue before and would have had heart failure if I went blowing a ton of dough on oil pumps and water pumps and what not for no good reason

And on that note, I'm going to go hook everything back up and take her for a spin and be sure it's the head gaskets before i get too crazy. Thanks again.