I have a 1995 Jaguar XJ6 VDP with 159,500 miles on it. For months, it makes a loud (embarrassing), screeching sound when it is first cranked. The sound continues until I begin to drive. I do not live close to a dealership and the independent shops have replaced the water pump, belts, etc. but the screech comes back. Does anyone have an idea about what the problem could be? I would greatly appreciate any suggestions.

 

I've moved your question from the Jaguar Forums Advice / Feedback & Suggestion Center section to the X300 section. The Advice/Feedback section is for posts about the forum and not for technical questions.

You've already hit the regular screech culprits of water pump and belts.

To help with suggestions, please confirm this only happens during cold crank and not on a restart with a warm or hot engine.

Graham

 

Get someone else to cold crank it, whilst you listen very closely to where in the engine the noise seems to be coming from.

Check your power steering fluid as well.

It could also be the harmonic balancer, we have many threads on this.

Simple question, but the replaced belts are the correct profile for the pulleys and are at the correct tension?

(oh and yeah, check that the neighbour's cat is not having a quiet kip overnight as your engine cools down, they can't half make a racket in the morning start up).

And finally a very long over due WELCOME TO THE FORUM, where have you been hiding.

 

Yeah we heard a squealing noise from a friend's Honda once but it continued after the engine was turned off so we popped the hood and a very unhappy cat jumped out and ran away

 

I bet the pulleys on the car have never been changed, the do make funny noises when worn. At least that was it in my case.

 

Graham,

The sound is worse in the morning - first crank. Sometimes during the day, after it has been parked for 5 hours.

Thanks,
Shelia

 

Richard,

Thanks for the welcome. I wish I knew about the belt tension, but I am unable to determine this. I will have that checked.


Thanks for the response.

Shelia

 

Be prepared for the possibility that the balancer is delaminating

Cheers
DD

 

+1

to Doug's suggestion about the harmonic balancer (crankshaft damper) delaminating.

See this thread for info on checking it:

https://www.jaguarforums.com/forum/x...alancer-84531/

Graham

 

Yes, please do the test of the harmonic balancer before you get carried away. I was all set to take the car to Motor Man and leave it there while he removed it and sent it in for overhaul. He then told me how to check it. I did. Still running with the same balancer and the three dots still line up.

Have fun.

 

Mine displayed all the same symptoms except that the noise occurred ONLY during cold cranking first thing in the morning and after standing for several hours. The noise disappeared as soon as the engine fired (you say the noise continues until you drive, does that mean it continues to screech whilst idling, before you move off?). I eliminated belts, water pump, starter motor etc and in my case the culprit was the timing chain upper tensioner. The problem went when the tensioner was adjusted. Yours may be a different issue and this may not help you, but I wouldn't rule out having the tensioner adjustment checked, they're a common X300 fault.

 

Welcome to the forum Sam. You should check the damper as EZ Driver said. But I'm betting whether good or bad, that is not the source of your squeal. I've spent the last 3-4 months and 5000 miles living with exactly the noise and circumstances you describe. "Cold starts" could be in the afternoon when it sat in the TX sun at 100 deg F 8-10 hours at work - still makes the noise until it comes up to temperature. Worse on first start in the morning and worse still if it's a cool morning - have I got that about right?

I'd probably be a li'l bit sick to my stomache about now had I not done the damper check and confirmed it as bad already - because I'm pretty sure I've discovered the source of the noise AFTER I bought $200 tools to remove it and sent it off to the Damper Doctor in CA. (I have reason to believe it has been rebuilt and is on its way back as I write, though I have no tracking info) I jacked around a couple of weeks getting the damper off sandwiched around a vacation trip and stuff...but didn't pull the belts off until I had a tool in-hand that I had some confidence would remove the bolt. So in the evening after I'd packaged and shipped my damper off, I got all giddy out in the shop regressing into childhood and spinning my a/c idler pulley with the compressed air hose. I've just got my index finger through the bearing race and it is spinning free, but I thought I heard the same pitch whine although very faint. No belt and load this time, as I say, spinning freely and no bolt and mounting bracket to amplify it through. Next morning, the pulley bearing was nearly seized. I broke it free but could feel much roughness in rotating it. I've had the dampers delaminate on the 3.0L S-type and the 7.3L Excursion, both made EXACTLY the same noise - a short sharp hi-pitched "chirp" on cold start for a few minutes. My XJ noise was nothing like that. Now, it could've also been making that chirp, but I wouldn't have heard it with the cacaphony emanating from the FEAD. Knowing what I know now, I'd change that A/C idler pulley and mark the harmonic balancer. If it is bad, you have some time to plan, that failure is not immediate. The aforementioned failures made the little chirping sound a good 6 mo to a year before they started tossing belts off. I'm not even yet persuaded the 4.0L AJ16 pulley will shed the belts. The damped pulley is the middle one - it is sandwiched in there pretty good - may only lose drive when it fully goes, rather than get a wobble.

Best of luck in getting it sorted, be sure and post back on your progress.

Some pics and part numbers can be found in this thread:
https://www.jaguarforums.com/forum/x...roject-100618/
The Jag plastic wheel can be a bit pricey...

 

Jagent, How do you adjust the upper tensioner? I have the same problem.

 

Working on the tensioners is a tedious process and I realised it required more confidence (and possibly skill) than I had at the time! I had mine done at the local Jag workshop. I needed it done fast and right. The upper tensioner was removed and new O rings fitted. Lower tensioner not touched. There are several postings on this forum, one in particular by "Christian" which goes into great detail if you want to DIY.