When I start my 95 X300 in the mornings I get a loud squeeling sound and the amp meter show little to no charge. A few blocks down the street the noise stops and the charge is at the 13+ amp mark. The local guy first thought belts so we replaced them but the noise was back the next day. Took her back and he thought tensioner pulley was bad but changed his mind because of the drop in charging; he now says its a bad alternator. Spraying belt dressing on the belts stops the noise and the charge returns to normal. So is it a bad altenator or a bad belt tensioner?

 

The best thing to do is remove the belt. Turn each by hand and feel for roughness. Or listen carefully to determine source location.

 

Sounds like the belt needs a little more tension

 

I don't think your alternator is bad but your belt and tensioner might need to be replaced . I sprayed WD40 in my Jag to stop sqeaks but that annoying noise came back after a while .
Belt and tensioner were replaced and no more idiot noises at all lol

 

Check the crank damper and I'll bet you find your problem.
The cheapest fix is to send it to a damper reconditioner.

Damper Doctor and others can rebuild it.

bob gauff

 

I have the same problem!!!! idk what to do ether

 

Hey, Sean, since we saw you at your grandma's house, my 95 XJ6 A/C belt has started squealing. I bought new belts and am getting ready to replace them. Haven't found any info on how tight to adjust them, but it seems like A/C belt self tightens with the idler pulley. Don't know about alternator belt tightening. I'll try just tightening to the same spot as old belt, but may not work with new one, because of slight stretching with age. (tried to edit title to correct typo: problem )

 

What are we all in the same boat? Mine just started to squeel in the morning. My crank damper has been replaced and all the belts. It just started this too, just like you people. Change in temperature? Just in the morning?

Doesn't go to the top of the repair list as my PO713 code is preventing driveability. Same mentioned in a previous post. I'm afraid a trans shop is going to rip me off.

 

The required tension for each belt is listed in the service manual on the Jaguar Heritage CD. The tensions are expressed in Newtons and can be measured with a Burroughs gauge. If you have access to a Burroughs gauge but its calibrated in lbs force, then 1lbforce = 4.448Newtons. The belt tension is also expressed as its natural frequency, but unless you have a Clavis Meter you won't be able to measure its frequency. The tension in all the drive belts needs to be set manually. No auto-tensions are used.

BTW, if you need to remove a component and want to refit it with the same tension, then I would suggest counting the number of screw turns used to relax the tension to remove the belt, and then reapplying the same tension when the belt is refitted. However, this approach cannot be used when replacing an old belt with a new one because the old belt will have stretched. Adjusting the tensioner to the old position will resulting in a higher tension, even if the replacement belt is "nominally" the same length as the old one.

 

I think my burroughs gauge and clavis meter must be buried under my crow bars.

 

Now that's funny. Mine must be in the same place..

 

Afollowup to my problem. The local garage first determined my problem was the belts so replaced all of them. A few days later the same problem was back. The garage then determined it was not the tensioner and belts but the alternator so a new one was installed. I questioned the need to replace the idler pulley and new belts and was told the previous belts had been stretched and the replacement was necessary to insure alignment with the new alternator pulley. Not much I could do but pay up. I took the old alternator to an auto electrical shop and they found the internal voltage regulator was defective but everything else was fine. So I now have a spare alternator and a new garage on my 'black list' of places to avoid.

 

I have a 1996 xjr and the compressor belt just blew apart while driving. At the same time, the alternator belt has been slipping. I now get to replace all three belts. I was checking to see why the compressor belt would have blown apart, but I don't see anything wrong. I don't know how to take off the alt belt, is there a tensioner? I just see it around the alternator, a pulley near my supercharger, and the engine pulley. I just wonder why the alternator belt was slipping and why the brand new compressor belt broke apart. Any thoughts?

 

I bought an old school belt tensioner at a garage sale in Gilroy for five dollars a few years back. Just checked, and yup it's a Burroughs gauge... As for the Clavis Meter, well, the missus is using it to determine her fertility cycles. You see she wants a big family. I just wish she would use the former on me and just give it a whirl, boy or girl...

 

Oops, double shot. Sorry...

 

You can use a cell phone with a suitable app to measure the frequency the belt resonates at.

 

I have posted a similar question "annoying noise" . So what fixed your problems?

 

I forgot to post after I solved my belt noise and alternator charging issue. It turns out that my harmonic balancer had come apart (the rubber damping components). I removed it, sent it to Damper Doctor in Oregon, I think it is, and got it back within 48 hours. Reinstalled it and it works like a charm; noise gone and alternator charging fine. I had to come up with a way to remove the old and torque the new, so I made a tool out of wood and used the harmonic balance removal tool rented from Autozone along with it. I took pictures of my tool, but basically it is a piece of 3/4" plywood long enough to seat against the engine frame to the drivers side of the damper with a fabricated round piece screwed onto it that fits inside the damper and the 2 bolts from the rented tool run though 2 holes in the wood and screwed into the damper holes. I braced it against the frame and bumped the engine. The whole thing flew off and I thought I might have broken something, but it flew off because it worked and loosed the damper bolt. I used it and a breaker bar to reinstall and manually tension the bolt afterwards. Cheap fix, but worked. I had to remove the fan shroud to get space, but that is super easy to remove and reinstall. Had to do it to replace alternator too, because the damn bolt at bottom is too long to get out without removing fans.

 

motorcarman right again.

 

Hey motorcarman can you visually see if the damper is bad? In other words how can I diagnose the crank damper. Your help would be appreciated. I am fairly new to Jaguar and in my spare time enjoy working on my XJ6. Problem is I currently have none.