Covertible pump large o-ring for oil reservoir 1995 xjs

My convertible pump seems to be leaking from the oil reservoir housing. There are many threads on repairing the main small rubber shaft seal on the pump motor but I am seeing the oil leak from the housing itself, so I am thinking my leak is form the large diameter o-ring on the plastic housing. I searched and found no clues on where to find the replacement part for this…anybody know where I can purchase a new o-ring? thanks!

This looks relevant.

yes i saw that thread and many others, but nothing that discussed the large o-ring. I think i will have to just measure it with a calipers and buy a replacement…maybe slightly larger to make sure there is proper seal.

I have a drawer full of new O rings.
Give me the measurements and I’m sure I can find a match.


Thank you for the kind offer! I fully disassembled the pump and I gotta be honest it is in pristine condition. I can find no fault in either the main seal or the larger reservoir o-ring, yet it seems to be leaking from the reservoir case, so I think what I’m going to try is to refit a thicker gauge reservoir o-ring to help make sure its really fully sealed. I still need to dig out my calipers and take the measure and will let you know in case you have something thicker and the same size I will gladly take it! thanks

Happy to be of assistance.

i measured 71.2mm ID x 2.55mm CC

I will go through my o-rings and see what I can find.
Is 2.55mm CC the diameter of the section?

yes, so maybe my measurement is slightly off… i’m guessing it’s probably really 71mm ID x 2.5mm CC

maybe i need something a little thicker like 3mm section. im thinking i probably need to custom order something so specific.

1 Like

I’ll edit my notes and get back to you.

I found a Viton one about 70mm ID and 3.5 mm dia.

wonderful! I’ll pm you

Hi Rubin

I recently replaced the loaded U-cup on the central shaft of the hydraulic pump, (PN UL125-0.375-125) from the oring store. The main lesson I learnt was to ensure the orientation of the wires (and hence polarity of the brushes) was correct during re-assembly

This shows the correct position of the wires.

Incorrect orientation causes the roof to lower when you want it to go up and vice versa.


1 Like

i received replacement o-rings and it looks like i measured wrong!!! dohhhh!!! and i somehow lost the original o-ring, double doh!!! feeling like such an idiot right now! also i ordered a replacement main seal in case, which i received but it is encased in metal, unlike the orignal which is all rubber, so the replacement doesn’t fit!! doh again! doh doh doh!!! this is the new metal clad one i bought, any way to take off the metal?