My 99 XK8 broke down on the side of the highway. Turns out out it was the belt tensioner.(Hopefully it won't be an expensive repair, my wife has been trying to get me to to sell it pretty much since I bought it) Wouldn't you know ur it, I am having a hell of a time finding a belt tensioner. Does anyone any suggestions? Where to find one, are there any parts that are interchangeable that I could get off another car that would fit on a Jaguar 4.0 V8 ? Any ideas would be appreciated.
Also, it is a convertible and one day, I lowered the top & the little back quarter windows did not roll up when I put the top back up & they haven't rolled up since. Once again, any suggestions would be welcome. Thanks in advance!!

 

Forum sponsor S N G Barratt list the tensioner assembly:

SNG Barratt - The Ultimate Jaguar Parts Specialist


(click on the image to enlarge it)

I live in England so can't give you any advice about convertible tops!
Graham

 

The tensioner is easy to replace and should take 1/2 hr for the novice I did mine and used the above part.
The windows could be several things, there are a few members quite knowledgeable in the roof functions and will chime in, sounds like your not getting the trip of fully closed relay which tells the windows to go up. Dennis will probably give you details OR do a search most of this information has been discussed previously.

 

If the tensioner still spring action and only the idler roller bearing went out you disassemble it and change just the bearing. The auto parts houses can match the bearing numbers. It isn't any harder than changing the tensioner, I did the bearing repair because of the delivery time for the new tensioner.

I buy a lot of parts from JAGBITS one of our forum sponsors. Great service, fast ship and usually good prices.

 

+1 on an easy replace for the tensioner assembly. However, if you are not the mechanic type, any competent shop can do this fix. It is a bolt-on replacement.

Any of the forum sponsors should have this part.

As to the rear windows, you have gotten the raise/lower electrics confused. Gus's repair site has this info: JagRepair.com - Jaguar Repair Information Resource but search the forum too. Many threads on the trials of the convertible top (hood).

 

More than likely the spring tensioner itself is still good. You can buy a metal (instead of the original plastic) replacement pulley made by Dayton at most auto part stores.

See my post here


While your at it replace the stationary idler also as it will likely fail soon also. Do not reuse the old belt because if it has a kink in it from being thrown off it won't stay on long.


Dave