First timer here!

Recently inherited my late father’s ‘04 XJR and evaluating whether to fix a shredded supercharger belt (and potentially keep the car for a while) or try to sell it as and save myself some pain/suffering. I have been quoted by two different local mechanics who work on old luxury imports $1500-3000 to fix the belt, but both have said they don’t know what caused the first one to fail and are reluctant to even try replacing for fear the new one quickly gets shredded because we didn’t diagnose the cause the first time.

These guys have also mentioned that Jaguar recommends an adaptor kit that is pricey and a bear to instal. On the other hand I’ve read something like this can be installed without the kit and it works fine: https://www.autozone.com/cooling-hea...377/317412_0_0

Anyone have experience here? Would love to get her back to full strength but don’t want to spend thousands without knowing what is causing the issue!

 

put new bearings in the idlers and send it…it’s a 2 hour job max even if you’re a sloth that’s blackout drunk

 

If it still was the original belt, then it has lasted a long time and it could simply be shredded because of age fatigue.
Jaguar has changed the belt completely, the old version was ribbed on ones side only, whereas the new version is ribbed on both sides. The old type of belt is officially not available anymore, and it seems that the new belt cannot be fitted with the old tensioner and pulleys, apart from the supercharger itself where everything remains as is.
I do not know where you live, but here in Germany I have paid around 300 EUR for the kit, and the installation was not much worse than only replacing the belt itself.

Best regards,
Thomas

 

As you used an AutoZone link, I'm assuming you're in the US. I replaced the SC belt on my '06 with this one from Rockauto:

More Information for CONTINENTAL 4080521 (rockauto.com)

That was about 60,000 miles ago, no issues since. The other guys may well be right that you need to change the bearings in the idler pulley - never a bad idea although I didn't, even though my car has over 200,000 miles on it now. A good way to check it is before you replace the old belt, watch the idler pulley with the engine running and see if there's any wobble. If there is, definitely replace it.

There's a few good YouTube videos on how to do the job (look at S-Type R as well - same engine). Can the belt be changed without draining the coolant and removing the expansion tank - not easily. Most will recommend the easy way.

Good luck!

Chris.

 

Like others have said, the SC belt is a relatively easy job if you're willing to drain and remove the expansion tank. Insane that a shop would charge $1500 to do this job.

While you're in there you can change your accessory belt and SC idler pulley bearing as well, SKF EXPLORER 6303-2RSJEM should be an exact fit.

Make sure to have 1/2" and 3/8" breaker bars at the ready as the tensioner arms have a decent amount of tension on them.

 

Thanks all, v helpful.

It sounds like consensus is that replacing the original belt that was shredded with a new (one sided) alternative should work fine, assuming it was a faulty/old belt that disintegrated. If we can do it without taking everything apart, that seems like a low risk maneuver.

If we’re taking everything apart and I’d rather be safe than sorry, sounds like replacing some old parts (just hit 120k miles) would be prudent — ie bearings in the idlers.

Any verdict on the adaptor package requiring the new two-sided belt? If the labor isn’t much more once everything is apart, should I go for that or just update the old setup?

 

Cheers — I’m going with this option and will find someone who is willing to give it a go. Seemed rich to me as well!

 

Depends on whether you can source the old version of the belt, or not. I would go for it, as it would also solve the matter of replacing old bearings...

Have you tried to spin the supercharger and the rollers by hand? If they spin freely, I would say that it was the belt, if they don't, then further investigation is necessary.

Here's a picture of the kit I bought:

Best regards,

Thomas

 

Hello, Thomas. Do you have a part number for that kit and a source? Not sure it would help me here in the US, but it might. I bought the Jag parts years ago, over $500US at that time. Probably NLA now. I know there was one bracket, LH side of the engine I think, that I did not use. Way too much trouble to access and change. That was 6 years and 50,000 miles ago and no ill effects from not using the complete set up. The kit you picture seems much simpler and would be good to have on hand.
Thanks,
Dale

 

Hi Dale,

I think that the kit was put together by the dealer who sells them here in Germany (Jaguar Hermann, www.jaguar-shop.com), but I also found this in the catalogue from SNG Barratt, which looks like the kit I bought:

As far as I know, SNG Barratt also sells in the US.

Best regards,

Thomas

 

Perfect. Thank you, Thomas.