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Richard, Jaguar Technician
Category: Jaguar
Satisfied Customers: 15492
Experience:  12 years at a Ford/Lincoln Mercury and Jaguar dealer as technician and shop foreman.
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Jaguar XJR: Hello, 2001 XJR 144k I am trying to gauge the

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2001 XJR 144k
I am trying to gauge the approximate cost of replacing one head as well as timing components. It seems this Jag may have "jumped a tooth"

Perhaps I am better off swapping engines with a lower mile recycled 4.0 SC?
Also, what year motors will work? Can a 2001 XJR receive a 2004-2006 4.2 SC engine?
Thx much!
Hello and welcome to

Did you take the engine apart to see if the secondary chain jumped or broke?
Customer: replied 4 years ago.



No, This is a Jag I am considering buying and fixing myself if the price plus cost of repair make sense.

I was told by owner that car is in "limp mode" and runs but that some kind of smoke is coming from one tailpipe only.

Owner was told by Jag aficionados that it was likely a "jumped tooth" (bent valve(s) scenario?) type of issue but it has not been professionally diagnosed.

This is all I have to go by.


My "guess" is that since it still runs it might well be worth repairing but I have no clue as to typical costs for parts etc. before I dig into it.

At 144K miles, if I buy it right, a good boneyard engine may still make sense.

I want to learn about these Jags. At the right price, this one could be a good platform from which to learn.

Thanks for responding.

It could very well be a problem with the timing but the smoking and limp mode it could be something more even another major mechanical failure like a head gasket. At this mileage your best bet would be to install a used engine. The problem is finding one. A 4.2 liter will not work as everything is different. For example wire harness, ECM, transmission and piping so this is not a possible option. Your best bet would be a 2001-2003 XJR engine. Here is an example of what is available. I personally also like the 1998-2003 XJR and also look to see if I can find one for a good price but have come up empty.


Click here



Customer: replied 4 years ago.



One last question. Are Jag specific tools required to do this job? (head/timing replacement...even engine swap, and if so, are they available in the after market?)


I'm in south florida and I see the XJRs on craigslist regularly...they sold a bunch here I'm guessing. the 98 to 03s seem to range from $5k to $10k.

I track the Manheim sales as well.

I have seen a few XKs with GM LS engines installed (nice fit too), but from what Ive read so far, the 4.0 SC is a fairly solid engine...i dont see the need to install a GM conversion.

Thanks again

If you were to swap in a new engine there really is no specialty tools needed. However I would install the new timing components (tensioners, guides and chains). This you will need special tools but you can actually rent them.



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