Window regulator/motor mechanism failure
 

Recently the front driver's window closing mechanism on my 1995 X300 has been getting slower and slower to reach full closure (going down is okay). In the last week, the window only gets to about two thirds closing before in stops. I can close it completely by pressing the close button in the door panel and pushing the window up with my other hand. Not a long term solution!
I was thinking whether the problem might be with the motor or the mechanism, but looking on ebay I see that it seems the mechanism and motor are offered either combined in one whole part, or just the mechanism.
As I don't know whether fault is with the motor or mechanism (suspect motor!) could someone please advise that I would be better buying the complete regulator mechanism? Would it probably would be wiser anyway to replace the whole mechanism in view of the car's age even if they were available separately?
Finally, I've accessed inside the door on several occasions so this would not be a problem. but is replacing the window regulator mechanism a job for the amateur or should I put it in to a garage to do the job?
Thanks.

Let's not jump to conclusions just yet. Have you lubed the rails that the windows slide on? I suspect once you do that, everything will get better.

You'll have to open up the door, but you said you've done it before. Just make sure you get your hands on some silicone paste. Then use your hands to apply it, liberally. Operate the window a few times, back and forth, and youre back in business!

If your window assembly is similar to the XJS, then you'll be applying the paste not only to the rails on either side of the window, but most importantly, there is a bottom rail, where some weird plastic piece slides back and forth as the window assembly moves up and down.


That's the product I use. If this doesn't completely solve your problem, and it will, then we can discuss window regulator replacement, which is something you can do yourself.

Thanks Vee, wise advice I think. No I haven't checked. And yes I should have! Did think about lubrication, but didn't know what best to use.
I was jumping to conclusions.
Will source the product you suggest and give it a go.
Thanks again.

I found one of the wires on the window control unit pushed out of the connector causing intermittent operation . They push back in and lock . You can verify mechanism operation before removing it by bringing the motor wires out of the forward opening and powering them up with a battery charger , just swap polarity for up or down . High current arcing hazard .

Thanks for that, coincidentally when I have removed and re-fitted the door panel on previous occasions, which necessitates unplugging the connector to the door window switches I have found on a couple of occasions, the window wouldn't work and it was because of a connector problem.
Worth a check I think.
Thanks again.

Update. Product recommended by Vee has just been delivered (import from USA). In the next day or so I will be tackling the job using it!
Fingers crossed. Hardest part is removing door panel!!

Well, followed advice and applied grease to all necessary areas. Pleased to report it seems to have done the trick, at least for now!
Thanks Vee for your advice.

Sounds like making new bushings & lube worked. My 1988 XJSC has a different problem: The ring gears are mage of a white plastic which has now worn out. Tried "flipping" the gears as recommended in another thread & it worked for a few weeks, but soon they broke again. Does anyone know if these worm/ring gears were used on any other vehicle? Will look for some pictures.