Could one or more of the experts out there please tell me the recommended interval between serpentine belt changes.
My 2005 4.2 has the dreaded front end "chirp" on start up which continues for about 10 minutes. If I lightly spray only the belt with water or WD40 the chirp disappears immediately. The car has done 60500 miles and according to service records the belt was changed at 43k around Jan 09; 47.7k Feb 12 and just before I got the car at 58.9k in Apr 15.
To my inexperienced eye the belt looks good and feels OK.
Any information or advice will be very gratefully received.
Mike

 

Our 2006 owners manual shows a serpentine belt change interval of 150,000 miles. But real-life conditions will certainly shorten that. My wife's XK8 is approaching 110,000 miles on its factory belt with no issues. No question that these belts are high quality, but 150,000 miles is asking a lot from them....

 

Typically, noisy belt is due to contamination. Spraying WD40 is not going to help as it will attract more dirt. I would recommend you figure out what is contaminating it. Typically, it is a weeping water pump, but it could be a number of things.

You can remove the belt very easily. The tensioner has a 3/8" square made for a breaker bar. Release the tension and pop the belt off the alternator. Then remove the belt entirely. Do a nice cleaning with a strong degreaser (detergent, or Simple Green). Check the bearings of all the accessories, including the idler and tensioner for play and anything other than completely smooth rotation. In my opinion, put a new belt in. They run something like $15. If a part needs more than 15 min to get to, and is cheap enough, don't inspect it, just change it.

Best of luck, keep us posted.

 

I had over 150,000 miles before I changed my belt. I saw cracks which was why I did it. If the belt is chattering on starting for 10 min it may be the idler pulley, not the belt. Typical symptoms, especially in cold, is a noisy or chatter, then goes away once warm. There are 2 pulleys so do both and get the right one.

 

IMHO spraying WD40 on your belt will cause it to rapidly soften and deteriorate, it'll need replacement right away.
Regards,

 

Agreed. If you are going to apply something to the belt, get a proper can of belt dressing....

 

Good chance the chirp isn't necessarily your belt, but one of the two pulleys.

If the tensioner pulley or idler pulley are tight, the belt will chirp until the pulley loosens up...

Ask me how I know this.... Because both pulleys on my car were on the way out and ultimately froze up and snapped the belt.

My advice is to not only have the belt looked at, but I would immediately rule out the pulleys as well.
A belt is under 50 USD and a worthy investment.

 

Changed on my 2005MY at 52,000 miles was a 20mins job & not worth putting off !!

 

If the belt looks good then it will be. Lateral splits on the outside from drying out or sections breaking off the inside are usually easy to spot. The squeal on startup is usually due to a contaminated belt. Once either coolant or oil gets onto them, the only satisfactory solution is replacement as cleaning is rarely effective.

That does seem an excessive number of replacements. It's worth checking the tensioner as has been suggested above.

Graham

 

Thanks to all for such a quick response.
For the record I can see no contamination or leaks, my application of WD40/water was once and only briefly following a YouTube video (ChrisFix) advising on how to investigate the noisy belt.
Have now booked the car in with my local Independent for belt change and proper investigation.
I will let you know what happens. Thanks again.
Mike

 

I really would investigate any leakage or those pulleys as suggested . . . I'm not really grumpy, but IMHO, although not overly expensive items, 4 belts in 4 moths is just plain ridiculous . . . and suggests you are just shooting the messenger rather than identifying and solving the real cause.

Best wishes,

Ken

 

Howdy Folks:
My thinking in general is, if you do not have a spare belt, replace your good old belt as a spare with a new one. Also carry the tools to change it. (see this link, post # 9 for my XKR double ended tool as a regular breaker bar is not slim enough)
https://www.jaguarforums.com/forum/x...engine-169919/

 

I can go one better than that. The belt on my XK was squealing on startup Winter before last. I bought a new one but the squealing just stopped before I had the chance to fit it. Old belt is still quiet eighteen months later and new one is still on the garage shelf. Got to show these Jaguars who is the boss.

Graham

 

Ken I think you miss read my post; it's only three replacements (so far), and they were in January 2009, February 2012 and April 2015. Still excessive even so considering the low mileage between changes.


Cheers to you.
Mike

 

So that's the answer/fix - buy a new belt, shove it in the boot or garage - problem solved.
Thanks for the heads up on that one.

 

Well, you can try, but in my experience, it only works if the replacement part is really expensive, and not returnable.

 

Just as a last resort, if it's not the pulleys giving out clean out the grooves where the belt sits in the pulleys - over time rubber can build up in the vee section causing the belt to sit higher than it should causing a squeak. I had the same problem on a LR Discovery years ago - tried everything until a tech at the dealership tipped me off.

 

In my experience of 30 some years as a service adviser/ manager, I never saw a serpentine belt fail on its own. They either came in contact with something or a pulley seized destroying the belt.

 

Aha!!! My comment, and perhaps that of GGG nearby, were based on what you wrote in your original post - January, February, April and now in May you are fitting a 4th!!! After 50 years around these cars, I'm getting good at the tech stuff, but still woefull on mind-reading (LOL).

Now that you insert the years as well as months, it makes a lot more sense to see you changing them every 3 years rather than every month, but I stand by my experience that this is still an excessive turnover, viewed against your mileages. Of course it's smart to have a spare, but these items are not considered routine replacements like fluids, filters and the like. When in doubt, IMHO, Jaguar's replacement intervals suffice.

Cheers,

Ken

 

OK Guys here's the result; belt changed - chirp/squeek gone.

My independent Jagiar specialist reported that the old belt was in good condition, so that is now in the boot/trunk as a spare. Secondly the pulley bearings are in excellent condition but the running surfaces were highly polished and that was the cause of the noise. Apparently he, very carefully, applied some emery paper whilst rotating to roughen up the surface. Job done in one hour; local dealer needed the car all day and wanted silly money.

Thanks to all that replied to my initial question.
Mike