My last convertible top hydraulic pump lasted only about 4 months (bought used on EBay) so I can either buy another used pump and try my luck or, if available, buy a rebuild kit. Any ideas? I hurts to keep the top up on sunny days here!

 

Are you sure it is the pump? They should not fail that often. Is it blowing the fuse? What color is your fluid?

 

To my memory there has never been a reported pump failure here.

Motors have failed due to brushes that can be replaced and there is a special diode internal to the motor that has been reported as failed a couple times. Also replaceable.

Be very, very careful working on the electrical connections on the pump. Disconnect the pump a foot or so away from the solenoid connectors. Those connectors are very fragile and irreplaceable.

 

There is a link in my sig. line below with instructions on trouble-shooting the pump motor. At this point think repair, not replacement.

 

The top gets about half way up or down and just kind of peters out. I've got to reach up and help it down or up. Fluid level is o.k.

 

That would be great if I could rebuild a unit as I have the old one out already. Any links to these spare parts you speak of would be appreciated!

 

If the pump runs it is unlikely it is the problem and likely does not need to be replaced or rebuilt.

Is your fluid yellowish brown or dark green? The old yellowish-brown fluid gels up with age and must be replaced. It can definitely cause this problem.

 

Thanks for all the links to the top mods! I use my top several times a day year round. It's depressing when the weather is great and the top stays up!

 

I'll have to check the fluid but the motor was swapped out with a used EBay unit and only the fluid in the reservoir was replenished. Is there a way to purge the system of old hydraulic fluid?

 

Motorcarman discusses the issue here:

https://www.jaguarforums.com/forum/x...27/#post192550

The Jaguar TSB 501-33AM describing the flush procedure can be found here: https://www.jaguarforums.com/forum/x...27/#post198097

 

You mentioned having to help the top along manually. It's OK to continue using it that way until you get the problem sorted. No need to put up with a closed top! Just don't force anything.

I agree that what you're describing does not sound like a pump/motor problem. You mentioned replacing the pump recently. Do I understand correctly that the top worked normally for a period of four months after that? This would indicate the problem might be something other than old fluid (though can't rule that out).

Feel around all of the hose fittings at the pump ... including the four hoses hidden behind the pump ... for any fluid leakage.

 

And just make sure the petcock on the side of the pump is fully turned in clockwise?

 

Check the fluid level to the top embossed line and the petcock closed. If they are all good take WD40 and spray the left and right ram shafts. At times the shafts will be dry and need lubrication.

Another question do you have a pressure reduction system installed fluid or voltage?

Gus
WWW.jagrepair.com

 

Thanks for the advice, now the top goes up twice as fast after replenishing the fluid!

 

Truth. I wasn't careful and snapped my solenoids while working with the pump a couple years ago. Top Hydraulics luckily were able to rebuild those parts (pump was fine), but for about $400 IIRC. Be careful in there!

 

Hey, your lucky! I got very little help when I had top problems. I still have a pump with a snapped off solenoid electrical connector. Have you checked your fluid level? Has it been changed from the brown, to the green fluid? Above is the question is the pump valve open? There may be hidden leaks in the hydrolics, such as a seal in the lift cylinders, as mine had. I pulled out the back seat (ha ha) and there was a puddle of fluid there. The foam of the bottom of the seat was soaked also. The system is expensive, dealer (*******) ship (Jaguar) wanted $4500.00 for a new pump. They hate I disparage the great company that builds Jaguars with the Fiat acronym (F=fix I=it A=again, T=Tony).

I found a used one for about $300! The hoses are too weak really for the pump, or actually the pump may be too strong. This sight talks about a valve assembly that reduces the pressure, I have not tried. Another is to put a large resister on the pumps power supply. Which I have tried. It makes a burning amount of heat, so be careful! Some reading had it the hose connections are at fault. Or the O rings were damaged. In any case, there could be a lot of issues. Check it out, go slow, be verrrry careful. I did my rear window regulator, and the cylinder slipped out from its pivot mount. I failed to notice. I ran the top up and down, then started having problems again. The right side cylinders movement had sheered off the upper electrical connector, so it lost control of the tops position. I am getting used to fix one thing break two! I will help all I can! I am learning too... my friends ask what is wrong with Chevy?