Just purchased an 02 XKR. After I bought it I discovered that my engine had the old plastic cam chain tensioners that need to be replaced. They stopped putting the suspect tensioners in these motors in 01, but many of the 01 motors were installed in 02's. A Jaguar dealer has the data base to confirm this. The senior Jag mechanic talked me out of doing this repair. He is doing it as comunicate. 11 hours of shop labor. I still love this car. I should have dug a little deeper before the purchase.

 

Your mechanic is being a little disingenuous, no doubt he is under orders to get lots of workshop revenue in. Lots of V8-engined XJ8 and XK8 owners here in the UK have had the important tensioners replaced, (the ones that can wreck the engine if not attended to). These are the two exhaust camchain tensioners, one tensioner for the chain on each cylinder bank. The other tensioners are not so critical. It probably does take 11 hours for doing the lot, including the main chain, but you don't have to do this. The reason these tensioners fail is because of the heat on the plastic body, and also the cyclic loads placed on them by the peculiar nature of the cam timing on a V8 DOHC engine.

You can even replace the top tensioners yourself, and if you really want to save money, one of the Lincolns has the same engine but Ford sell the tensioners for these at a lot less money - see other posts on this forum !

 

I also have an '02 with the plastic tensioners. Replaced them with the Ford (Lincoln) tensioners from an '02 Lincoln LS for about half the cost of Jaguar parts. The Ford parts came in a box marked 'JAG' along with the part number. Changing the secondary tensioners solves the critical failure issue. Here is a link to a great pictorial on the work. Remember that only the secondary tensioners are critical unless you suspect that the car has significantly over heated.

http://www.mediafire.com/?mijhydngtog

If you can replace the spark plugs you can replace the tensioners. You will need to obtain the Jaguar tool set which is available for loan plus a $10 set of sockets and a 10mm Allen wrench. Four hours later you can brag that you changed your own tensioners.

 

Does anyone have the exact vin # or the changeover data from old to new? I have a 2002 xkr as well, and assumed it had the newer tensioners. Is there anyway to tell without getting into the engine? Thanks, DaleD

 

Sure! The conversion to metal tensioners occurred supposedly at the start of '02 model production but that is not absolutely true. The conversion date was August 13, 2001 at the engine plant. Since the engine serial number encodes its production date the first upgraded engines had a serial number of 010813hhmm. The 'hhmm' has not been reliably reported.

There is no direct relationship between engine manufacturer date and vehicle assembly so a car with a September '01 manufacture date cannot be guaranteed to have the metal tensioners.

The engine serial number really cannot be read in place but can be obtained by asking a dealer to look it up based on the VIN.

 

Thanks Test - Good information. I have an assembly date of 11/01/2001 - Should I feel safe that it has the new tensioners, or should I investigate more? There are no issues or sounds from the engine at the moment, and with only 30K miles, they may not be bad even tho it is 9 years. I'm not losing sleep over this, but if there is a chance, I'll look into it. DaleD XKR

 

Hey Gray - what is the assembly date for your 02 XKR? Mine is 11/1/01, and I've been assuming the tensioners were the newer ones - perhaps not... Thanks, DaleD

 

Just got my Jag back from the shop. End result: Frozen lower tensioners on cam chains replaced. Stretched upper (transfer) chains replaced. Upper tensioners replaced. Leaky water pump replaced. New seals here and there and it's ready to roll. Not only have I fixed the only Achilles Heel on this car but I managed to wade through the conficting advice I was picking up on the blogs. My advice is don't do anything unless you are willing to do it right. I feel so good about all the money it didn't cost me that I ordered a Mina Gallery fresh air, overdrive supercharger pulley and exhaust kit for my special ride. I've built several drag engines from the block up but the best move I've made in quite a while was to let the dealer's senior mechanic handle this one. Take your Vin # to a dealer if you are not sure about the tensioners. Their data base will pull it up with just a few key strokes.

 

I agree,too many times I worry about things after reading the blogs.Keep us updated on the Mina upgrades,I have done the air intake and the pulley,and have been thinking about the exhaust.Let us know you like the new sounds your cat makes.