One of mine started playing up. I found a fix which worked for me. A small piece of rubber hose wedged into the bottom of the runner. I thinks it’s the middle slot. This stops the regulator bottoming out and the rubber gives the motor a a helping start on the way up. Mine only ever stuck in the down position. I accessed mine through the air vent in the door opening.
Rob.

 

I had thought about measuring the gap below the window assembly when down and thought about finding a foam rubber, or just plain soft rubber ball that was just a little bigger to give it a little "boost" up. Of course my luck it would end up stripping something and completely destroying it. Smh

 

My 93 has had the windows up for years now since I gave up banging on the panels to get them to move. It's another Jag quirk we live with, but in the up position I get a little less wind buffering and I don't worry about running the A/C with the top up or getting caught in the rare Monsoon rain storm with 1/4 windows down.

Question here: I'd try the 40amp relays if someone has a source, or part #. I'm assuming they replace the "pink-purple" color relays, yes?

I feel everyone's pain...
Dave in AZ

 

The window drive motors draw roughly 3 amps when moving the window, and 10 amps when stalled at the end of travel.
If they lock up at end of travle more likely it is the rubber "spider" in the gearbox that is not functioning as it should.
Lots of discussion about the subject both on this forum and Jag-lovers forums.

 

I think it's the purple ones, but I can't remember the original colour. I used Panasonic ones from Digikey: https://www.digikey.com/en/products/...1-R-12V/646987 They were showing out of stock when I checked, but also look at Mouser.

 

It is important to make sure that the motors have the 2 small spacers under their mounting screws or the motor is misaligned with the regulator causing it to bind when it gets to the limit. Most people lose them when they dismantle.

 

Yes I've been lucky in that mine are all still there lol

 

Is it just me,,, or is the XJS ALLLLLLL about, the spacers...
Jeeeeeeze Louise.

 

Interesting info on the current draw, Richard. Any info on where to get a replacement rubber “spider”? I’m reassembling my motor mechanisms since I now have them operational but broken bits of the spider came out when I initially opened up the gearbox. Now would be the time to replace them if they are available.

 

I think that "spider" is essential to make sure the worm wheel does not bind at end of travel.
It was not put there for fun, it has a purpose.
For sure when I had window trouble I found the spider in the gearbox was distorted and not doing the job it was intended for.
After I repositioned it and coated it with rubber grease it has worked without trouble for the last 2 years.

I am not sure you can buy a spare spider, it is not the sort of thing the motor/gearbox manufacturer would offer as a spare.
There may be a specialist repairer someplace has managed to buy a stock of them.
I have a 3D printer in my factory and I asked the expert if there was a suitable rubber could be printed to make the small rubber seal that engages the pin at the top of the windscreen corner on my convertible. He said there was but I have not tried it so far.
A better bet might be laser cutting the spider shape from a sheet of rubber.
If there were a reasonable market for that item a form tool to cut the rubber would work, it should be quite cheap.
I found that with my window raise motor/gearbox on the convertible they could be cleaned up and made workable quite easily.
The spider being rubber might not last as long as the other parts involved, so it would always be worth putting a new one in if available.

I suggest you try an industrial rubber supplier in your area

 

Good information and I agree, the spider is not there just to fill up space. My problem is that the original piece has been chewed up and is effectively useless. No chance of making a copy. It seems to work ok on the bench and stops at the end of each way travel so I think I am just going to put it back in as is until I can find a good used unit.

 

So I opened up my right motor and it looks like there was enough play in the shaft (I think from wear in the black plastic cap type thing with a hole in it) that one of the brushes actually was able to come out and jam itself between. I remembered someone making new plastic washers for theirs and I did the same. It still didn't work, so I checked continuity and sure enough the one brush read really high. I figured the thermal safety or whatever it's called had blown out so I decided to try bridging it to see if it would work. It spun great in both directions! Yay! I thought. So then I put it back on the regulator and tried it a couple more times! Yay! Then I fought and fought to get it back in, and finally got it to go in. Hooked everything back up and...... ARGH! it didn't work ARGH! I knew my solder job was pretty bad, and knew I should have redone it, but it was ninety few degrees and I just wanted to be done. Oh well looks like I'll be keeping an eye on ebay, and trying to convince the wife I need them lol. Smh. I'll probably just open them up again and try doing it properly first. Oh well

 

I know this issue is a little old, but it is ongoing for me. My 1993 has the same problem, has anyone tried the Dorman Power Window Motor from a Mustang Convertible. Its hard to tell the diminition, but the photos are close. May be able to use the armeture or other parts to fix the Jag window. Any thoughts?

My motor has a sticker with an "Delco Products / Made in England". Anyone know where to get a Part Number?

 

I think I saw those at one point and thought the same thing. I have thought several times about just ordering new motors thay look close and see if i could even "make something work". I just haven't yet. I did see someone from the uk is selling refurbished motors on ebay and say that they are brand new motors, but I kinda figured they wouldn't just tell people what they were using since they're making profit off of it. As for the delco part number, I dont remember what mine says, but there is a number stamped in the case.

 

My experience with the Delco motors mounted on the window regulator is that they can usually be made workable. The thing many people probably miss, or don't understand, is that the rubber spider in the gearbox has to be functional or the motor will drive to end of travel and jam.
Apart from that problem everything might be working well.
The rubber spiders are not a spare part you can buy.
Maybe it would be possible to jury rig the thing and squirt silastic into it so that you form a spider.

 

Just to add to this thread, this question has been asked for the late convertibles over on the Jag-Lovers forums:

https://forums.jag-lovers.com/t/is-t...ative/382279/4

One owner sent me his broken internals, and I tried to create a CAD model of them for recreation through one of several methods: FDM, Molding, SLA Resin & then a recast in something durable, etc.
Link to Thingaverse Files is in the thread above. AFAIK no one has yet tried to make the files work to confirm that they do.
~Paul K

~Paul K