As promised, here my seat-adjust DIY Guide:

https://www.jaguarforums.com/forum/x...4/#post2630273

Btw.: When I wrote above that the spindle of the seat height-adjust motor is 11cm long, that is only half-true. I realized meanwhile, that there are TWO motors, which are doing the "heavy" lifting (height): One lifts the front of the seat, the other the back of the seat. The motor, which lifts the front needs a 11cm spindle, the other one most probably a 14cm spindle...

 

Update, job done.
Agree, one is 11cm, one is 14 cm.
I tried both options, buying just the gear, grinding the plastic gear off, then the knurled part of the shaft, then thinned the shaft, then cross drilled for the pin to hold the new one.
Also bought an 11 cm version with gear attached and trimmed the head off the old one, pried out the kinda C clip and moved the hardware to the new shaft.
Not sure which was easier, but perhaps the gear on shaft kit meant less concern about drilling the hole in the correct location/straight through the middle of the shaft.
Seats seem to work fine now, front and back lift on both passenger and driver sides.

 

Yes, there are the two options of either replacing the plastic gear only (with a metal gear) or replacing the complete part with the spindle attached (of course all metal). I figured as the cost-difference is not that great I swapped the complete part.

 

So now the forward/backward movement has ceased working on the driver's side.
The motor runs fine and the flexible drive shafts from the motor to, what I assume is, a gear box turn, so it looks like another broken cog type issue.

I also note that on the right hand side of the seat, on the runner assembly, there appears to be a sensor that detects the forward/backward movement. This was not mounted on its bracket. Looks like a couple of rivets should be holding it, those are in the bracket still, but the sensor is free.
Could also see that the position of the gear on the frame was different between the two sides of the seat, suggesting one side ran for slightly longer than the other and the seat was therefore slightly twisted because of that.

I guess I will see how much I can remove and dismantle, then see what replacement parts are available. Hopefully it is the same cogs as the up/down motors, although the gear box looks pretty small.

Update, yup, broken cog, seems to be slightly smaller diameter than the metal gears bought on eBay. The two parts of the gear box will not mate with the cog from up/down nestling inside. I guess I need to look for new assemblies or a seat.
'Tis not good weather for wandering around pick n pull though.

 

A quick trip to the scrapyard (pick n pull as they are known locally) yielded a pair of threaded rods from the passenger seat of a 2003. I removed them in the yard, and then opened the gear casing to confirm the plastic cogs were good.

Took 35 mins to install in the drivers seat of my car and all is back to full functionality.

I did get a response from eBay seller "ld-parts-service" who said they did have the appropriate sized cogs in stock, presumably in brass as for the height adjusters, just in case someone else wants to go down that road.

 

I saw your renewed threads above a few days ago, initially thought, I should remind you of my link I gave you already, but then decided against it - I did not want to repeat the obvious.
But since you are buying now plastic gears from the scrap-yard, it looks like you may never have had a look at my link above...
Hence, while your new old plastic gears may last now a little while longer, seriously have a look at the metal gears next time your plastic gears have disintegrated...:

https://www.jaguarforums.com/forum/x...4/#post2630273

 

Hi Peter,
Thank you for the reminder on the brass cogs for the seat height adjusters, which as you mention, was a little obvious.

If you read my posts, #44 and #45, you can see that I was talking not about the height, but forward/backward motion and that I detailed that the broken cog is not the same size as those readily available on ebay, etc. that are designed for height adjustment. This cog is much wider, and of marginally smaller diameter than those. If it was to come already attached to the drive shaft, that would have to be 28 cm long, not the 11-16 cm that typically are offered.

You might also note, that as guidance for those that might follow after us, I did mention a seller that replied, from the UK, to say they believe they have this different sized cog in stock. I have not confirmed the accuracy of that, and the cost looks to be around $90 for a pair if someone were prepared to gamble and confirm if they would fit.

My pressing need was to get the car back on the road asap, else my daughter might come after one of my cars, so a quick trip to the scrapyard was much preferable to waiting on international shipping. and as a bonus, produced a saving of 78% on the cost.
Being an optimist, I hope that these plastic cogs, that seem to work well for most X-type and Mondeo owners, last long enough for someone else to prove if there are brass cogs available that fit and work well.
I am sure it will take longer than 35 minutes to swap out both sides though :-)

 

Different electric seat variants and adjust functions on different X-Types feature - according to what I found - gears of 11, 14 and 16cm length.
If your problem-part is indeed 28cm long, I did not come across that one yet.
I saw however those gears on their own, but if the size you require is indeed different to that one, too, then I am currently out of ideas - i.e. ideas what to do, when the plastic breaks again...

 

Hi Peter,
perhaps these will aid your memory, fron the first and last photographs in your set at https://www.jaguarforums.com/forum/x...4/#post2630273

These were the details of the cog that I noted.
20 teeth
25.9 mm diameter
12.7 mm width across the teeth but 24.0 mm for "axle" length
shaft is 8.67 mm

The ebay seller has replied to say that there are only 2 sizes of gears (which I think we agree with, all the height adjusters are the same size cog, then a wider cog for forward/backward) and they sell them both.

from the first photo, the zoomed out location of the 28 cm threaded rod



and with your ruler close by for length estimations

 

I see. And that 28cm long rod is powered by a motor? Then I can only hope, my plastic-gears on that one will never break, as this would be a problem...