Over the last few weeks my '97 3.2 Sport has developed a screeching noise on start up, it lasts for about 2-3 secs immediately after firing. It's pretty loud (turn heads for the wrong reason!!) and happens on about 95% of starts. I thought of starter motor, or water pump or drive belt as possible culprits, but I am suspecting its the starter motor releasing since the noise doesn't appear at any other time except on starting.

Can't find any posted comments on this problem but would appreciate hearing if anyone else has had this experience, or any ideas??

Cheers,
Tony.

 

It sounds like your start motor drive. The overrun clutch is failing to withdraw the starter motor pinion from engagement with the ring gear once the engine has started.

 

Replace it now or there is a tow in your future. Same thing happened to me in my '95 XJS in November.

Good luck

 

I also found this on another forum - seems to be a common issue.

Might try the strip and clean approach this spring

 

Update: Last week I had the starter replaced with a reco unit by a respected Jag specialist (not dealer). Seemed fine for a couple of days, now the noise is back but less often, seems to happen mainly when hot and been running for a while, then stopped and re-started an hour or so later. Seldom if ever happened when cold. I suppose the reco unit could be suspect, but by leaning under the bonnet and reaching back through the window to start up, I'm now getting the impression the sound is coming from the front of the engine around the pulleys area. Who knows, sound travels! Anyway its going back to the mechanic next week for further investigation. Unlike some who can evidently live with it, it bothers me and I want to find out what it is. Will report the findings, if any.

 

I know this is an older thread, but I am experiencing the same infrequent but present starter "run on" that I've had happen on other vehicles where the gear isn't fully disengaging after the starting cycle.

There is a link in the thread above to some apparent maintenance suggestions to avoid replacment of the starter, but the link is no longer good.

Does anyone have any maintenance/cleaning/other tips on repairing the proper function of the starter to avoid just letting it wear out and then replacing the whole starter?

.

 

Al, I know this doesn't directly answer your question as my starter wasn't over running, but FWIW my problem turned out to be the TC upper tensioner causing the screeching. I had been so convinced the starter was the cause that I replaced it with a reco unit before finding the real culprit!

 

"TC" ??

Thanks,
Al

 

TC - Timing Chain. The upper tensioner is something of a weakness apparently, mine just needed adjusting (now at it's max. adjustment) so in future it may need replacing. The screeching sound lasted for 2-3 secs after releasing the starter which is why I was sure the starter was as fault, but not so. And yes, the noise did turn heads!

 

Ah, thanks. How many miles did you have on the car when your upper tensioner started making the noise?

.

 

Had done only 130,000km (around 81,000 mi). I believe the timing chain stretches over time and may ultimately need replacing. Since my tensioner is at max adjustment now, if the "noise" symptom ever reappears I guess that'll be the time to do it.

 

From what I have read on these forums, a screech on start up can be the rubber delaminating in the crank pulley. Putting a couple of chalk marks on the outer and inner parts of the pulley and the seeing if they do not line up after a few starts and screeching will tell you if the pulley is separating. Have you also checked drive belt condition and tension?

 

Mine really sounds like the starter engagement "run on" I've had on other cars, but we'll see.

I'll check on the harmonic balancer as well.

.

 

Balancer noise is more prevalent on cold starts and lingers after the start until you get up to optemp. At least in the beginning throes of failure. (speaking as one who has had 3 fail on 3 different vehicles...)


Still, given the complexity & cost of the verification test....can't hurt to check it!

 

My starter would make a horrible noise for a second, just after cranking as the engine fired up and the key was released. It sounded to me like a dry starter bearing. Ideally I would like to remove the starter for service but it is very inaccessible on the XJR. I put a bit of oil on the starter bearing at the ring gear end and this has cured the horrible noise.
The torque converter cover is a steel pressed part attached under the bellhousing with small bolts. I removed it and reached up into the bellhousing with a screwdriver with a bit of oil-soaked rag tied to the end and carefully daubed some oil onto the starter bearing. It is quite hard to see the starter up there so a good light was necessary.

 

Did anyone ever figure out what this problem is? I have had it on my car since I bought it 6+ years ago, and have never suffered any ill-effects or been left stranded by it.

I had to replace my harmonic balancer (crankshaft pulley) about a year ago because it had completely de-laminated.

The related problems (crappy running, scary noises at idle) were resolved, but the 1-3 second screech on startup didn't change at all. Sounds to me like the started solenoid isn't disengaging quite quickly enough.

So... anyone have a conclusive diagnosis? Solution?

 

Well, my clatter at startup turned out to the timing chain upper tensioner.

.

 

After reading up on it some more, I'm now convinced it's the tensioner, I have other things to fix first but that's now high on the list given the cost and ease of replacement.

 

Hi John,
The topic of upper timing chain tensioner noise is a very well ploughed furrow on the forum! See for example the thread currently on page 2 " note: the upgraded tensioner on X300 can also fail", with a mere 9500 posts! As a fellow sufferer, who has been trying to resolve said rattle for some time, let me summarise: The bad news is that there is not as yet a definitive cure, the good news is that there are no reported cases of problems extending beyond the annoying rattle at startup.
My own homespun current theory is that a longer and/or stiffer spring is required, but I am still waiting feedback on that from those with greater knowledge.

 

I've found there are two types of "newer" tensioners, I've both on the work bench and the ratchet on one is different then the other. ( larger more spaced rachet teeth) I ended up extending my spring with a little prompting then I ground down the ears that hold it in the retracted position to where it would just hold it and all that is required is a light "Tap" on the back to get it to fire. The current ears are pretty hard to get it to fire and in some cases it has been pulled out on cars with many miles on them in the non-fired/extended position.