I just purchased my 1989 XJS and the top is not working properly. It is a low miles car but has not been driven in a number of years. I purchased a disc that has all of the manuals. I specifically found the section that explains the convertible top system, pump and cylinders. I do not see anything about bleeding the system other than using JLM 10153 fluid. I have not checked on availability of that fluid. My question is on bleeding the system. I do not see instructions on specifically how to do this. I am assuming that this can be performed as all convertible tops are done. I see the filler plug on the pump. I have a kit with a one gallon jug and plastic lines that I use on convertible tops. That being said, I find it difficult to believe that this procedure is not in the manuals. Questions:


1) Does anyone know if bleeding the hydraulic top procedure is in the manuals?


2) If not, has anyone flushed out the system, re-filled it and then bleed the hydraulics? Any tips on how it is done?


3) Is JLM 10153 fluid available? If not, what is the substitute?


Thanks for the help

 

Just make sure you use Royco - 756 Hydraulic Fluid, Mil-PRF-5606H

 

thanks

 

There are 2 versions of the 5606 fluid: A and H. H is the current spec designed for "super clean" aircraft hydraulic systems, and A is the older spec. A is often cheaper and will work for our applications.

I got a gallon can from Aircraft Spruce for a reasonable price. https://www.aircraftspruce.ca/pages/...ps08-13851.php
They have US outlets too.

For bleeding, just run the top up and down a few times and it should self bleed. However, the reason you need fluid is there is probably a leak, so be prepared for that. The rams on each side do leak occasionally, if you see a puddle coming out the rear seatbelt mounting bolts then it's the rams!

 

Are you talking about the cylinders or the pump? Can these two fluids be miked with what is in there now or should it be flushed?

 

Cylinders. That's what's currently leaking on mine. The fluids are compatible and do not need to be flushed.

They are light hydraulic oils, spec is a viscosity of ISO 13. Most oils are heavier than that, ATF is about ISO 35 for instance, and very common hydraulic fluids are 46 and 68. All too heavy.

 

thanks

 

On mine, someone had put power steering fluid in it. I had to remove the pump, cylinders, and lines to clean it all out. Using the correct fluid, it works like a charm. Wrong fluid puts too much load on the fuses due to AMP draw. But I also replaced the seal inside the pump. But even that requires paying close attention to these little ball bearings in there, that are part of the check valve. Lose those, pump won't work at all. There is a thread on here on it.

 

I think the remaining fluid in mine is original but who knows? I think that I will flush mine out and start fresh

 

From what I understand, that seal in the pump is very common to go bad. If this system is low on fluid, and the pump seal is bad, adding fluid is futile. I got the seal on eBay for about 14.00 I think.

 

I have removed my top pump from my 89 xjs. There is no fluid remaining. Fluid is on the floor all around the pump. Can't see exactly where it is leaking but no it is coming from the pump. I do not see any fluid by the cylinders so I suspect that they do not leak. I cannot find anyone that sells the seals for the existing pump. If someone knows of a supplier or has part numbers for seals, please advise.


If I cannot find the parts, I found an aftermarket pump that should work if I use my existing by pass valve. The pump comes from Hydro Electric. Has anyone used one of these before?


Also, my guess is that if I use this pump, I would no longer need the special aviation grade hydraulic fluid. I am just guessing on that one but the pump manufacturer recommends ATF trans fluid. Not sure how that affects the cylinders.

 

This is the seal I purchased. I used the correct fluid, (also purchased on eBay for about 8.00 I think). The repair manual says the top should fully retract in 6 seconds. Mine does now. Maybe 8 seconds to go up. I highly recommend this repair and fluid.

NEW JAGUAR XJS CONVERTIBLE TOP HYDRAULIC PUMP MOTOR SHAFT SEAL

 

ROYCO PETROLEUM BASE HYDRAULIC FLUID ~~~ FULL METAL CAN

 

I have the correct seals for my pump and the correct hydraulic fluid. I believe that I may have a leak at the driver side cylinder.


I looked in the manual. I have the disk with all years, parts, etc and cannot specifically find where it talks about pump and cylinder removal. I would also think that there would be a section on bleeding the system. The section that I found on convertible tops is more general and not specific as to this issue.


Can anyone tell me specifically where to find this information in the manual? What section, etc?


Thank you

 

It's under the body section, under Convertible Hood and the Hood Hydraulic system. Section 76.86.00 and onward. The rams are 76.86.03.

 

Thank you. I found the section that you mentioned? I have the pump out. That was not a problem. Seems like access to the cylinders is the hard part. If I am reading this correctly, only the stowage compartment needs to be removed. Correct?
Does the side interior panels have to be removed?