Need to look at the one you have: two types, one is flat, like the one you show; the other has retention lips on both sides. Gates 36270 lipped on Amazon for 17.04; smooth appears to be Gates 36086, ~$17.00 on either EBay or Amazon with free shipping and two day delivery. Original from dealer exceeds $130.

I bought the Welsh unit, didn't work, too small (smooth type); put the old one back, works fine.

 

Where did you see that?

I can find no reference in Jaguar documents to the tensioner assembly being a time elapsed or mileage replaced item.

Graham

 

The set of four bearings needed to rebuild all the idlers and tensioners on a SC model costs about $20. Half that on a NA model.

 

Do you know of any specific place we can order them? Might you have part numbers for the replacement bearings?

 

I follow the line that the chirping is caused by the protective layer on the belt wearing off, causing the dry belt to slip on the roller.

A cold belt will probably have some memory of the tightest bents it was resting at, and this will cause a very short jitter while cold and passing the tensioner roller.
If the protection layer is gone (in my case after some 6.000 miles), it will start to make the chirp.

I soaked it with some anti-squeak spray while warm, and it has stayed quiet ever since, although I expect it to come back after a while.

Solving the problem by replacing the roller has probably more to do with the material of the roller or its coating then the design.

E.

 

It's in the standard Jaguar servicing schedules.

 

I started my car up with hood open and really listened and visually inspected the belt. Other than the squeak, which didn't last too long this time, everything looks good. I was reading somewhere (I'm pretty sure it was in my PDF shop manual) how to visually determine if the belt is worn and needs to be replaced. The belt looks almost new. I'm thinking it was changed out before I got the car, but I can't be sure of that. While I was inspecting it, I did notice the chirp coming more from the passenger side than the driver side (US). I am reluctant to change out the tensioner and belt at this point - some times I just like to leave well-enough alone.

So, let me ask this -- assuming the belt is okay, as well as the tensioner (since I couldn't hear any chirping coming from the tensioner), and assuming the chirp is coming from the passenger side, what is the "best guess" as to what could be wrong?

I'm thinking it could be the idler pulley, which I don't have a replacement for at this point.

Another question -- if I do take the belt off and run the engine for a minute or two, what can I expect to hear? If the chirp is caused by the water pump or the alternator, for example, and since those things won't be operating without the belt, then I'd hear no chirp, right? But, if the chirp is coming from the idler pully, for example, that I'd also not hear a chirp, right?

So what would be the advantage to running the engine without the belt? What could I learn from doing that?

The only thing that comes to mind at this point is that running the engine without the belt, if the chirp continues, then it's nothing that moves because of the belt. If there is no chirp, I don't see what I've accomplished.

I guess my question is this -- assume I remove the belt and run the engine and I do hear the chirp - what could possibly be causing the chirp at that point?

 

Reread number 16. If you take the belt off and the chirp is still there, the motor is the problem. If the chirp is gone, then the problem is with something being driven by the belt.

If you have the new belt, like you said you ordered, and you take the old belt off then put the new belt on not the old belt. For $10 at advance auto parts, you can buy in the Mechanics stethoscope. If the noise sounds louder, now, on the right side, then it is likely the idler pulley or the alternator.

In fact, if it was me, I would buy the stethoscope and check out the moving parts before I
Removed the belt.

 

Thanks Jim -- I wrote my last post with #16 in mind. Now I get it -- some times I'm a little dense. When you say "motor" what parts could cause a chirp? That's what I was getting at.

If I take the belt off, of course I'll put the new one on.

Also, I have a stethoscope but not sure what moving parts to hit it with.

The best tool is not a substitute for knowledge...

 

That part I can't help you with.

With the stethoscope, touch the block nearest a moving part driven by the belt -- what is toughest here to hear is the noise goes away after a few seconds of running - ne?

 

As with every project I have undertaken on this car, I have to give a huge shout out to all my friends here, in this case especially to Jim, for all the encouragement and advice.

I replaced the tensioner and the belt -- NO MORE CHIRP!!!!

After mulling it over for a little while this afternoon, I decided to bite the bullet and just go for it. As you know, it's not a difficult task, but I'm always overly cautious when undertaking a task that I've never done before. So, it took me ½ hour or so, but it came off without a hitch and went back on easily. I started it up, and what a beautiful, chirpless purr this engine has now!

Thanks for all the help!

Only one thing to note -- I went for a short test drive and had the CEL come on and restricted performance. I didn't notice this until I was pulling into a parking lot to turn around. I put my code reader on it and got three codes P04xx (can't remember the xx!!!), P1642, and P1111 (I know, nothing to worry about here, but wanted to report it for completeness). I erased the codes, turned off the engine, restarted it and drove home with no codes. Hopefully it was just a fluke!

I'll be starting a new thread if I find I have some new problems, but for now I couldn't be happier!!!!

 

Super

 

My wife's car has been chirping for a few months now. So today, I picked up a similar smooth pulley from Auto Zone and a new belt. After a few minutes the old belt and pulley were off. The new pulley went on easily and the belt followed. With fingers crossed, I started the car to chirp less bliss. I am hopeful that this fix will last for a while.

Good luck with your quest.

Jamie

 

My '99 XJR has the cold start chirping of the accessory belt.

Here is the interesting part though, my XJR was stuck in the previous owner's estate for nearly 10 years after he passed away. After that length of time in storage, the family took the car to a Jag dealer and had them go through the entire car, replacing belts rubbers and anything else that might have perished during its time in storage.

So given that I have new belts and the car only has 35'000 km on it or 22'000 miles, can it be the tensioner? Going back to the first post on this thread - did the lube on the flat side of the belt work?

 

I recently replaced the original idler pulley with the metal one shown above and immediately got a loud cold start chirping. I replaced that metal pulley with a plastic one (Gates 38023) and the chirp went away (almost). It's no longer audible from inside the car, and you have to open the hood in order to hear it.