In early September I replaced my convertible top hoses and the latch cylinder. When the job was done I tested the roof operation several times and all was well. (I have the pressure relief valve installed, but I`ve had that on the pump many months prior to the new hose install). Now though, when I push the top down button, the front windows go down an inch, the rear windows go down, I hear the pump and then the pump stops, the front windows go back up an inch (rear windows stay down) and I hear the "ding" sound as if the operation is complete (but the top has not moved at all). If I then push the roof down button again, the top will then go down. It goes back up normally. I guess I don`t mind pushing the button a second time in this two step manner, but I can not figure out why this is occurring and how to fix it. I`ve had folks say it`s air in the lines and will self purge, but after lots of top operation, it is still doing this.
Any ideas? Thanks.....

 

When the front windows go down do they go all the way down or just drop a few inches? When operating the roof is the engine running?

 

Gus...the front windows drop just a few inches and I usually have the engine running. Also, when I raise the top, if I immediately lower it it WILL go down normally with one push of the button. I truly believe this problem is related to air in the system. I do hear a bit of a squishy sound initially when I hit my top down button. I don`t know if opening the fill plug on the pump will have any beneficial effect on purging air or maybe trying to run the pump with the T handle valve open would do anything to help either.

 

I have been told that the system is self purging but I am not sure how that is done. This system is designed so when hyd fluid is pushing the same amount of fluid is returning back into the system. Air will compress but hyd fluid will not but it could aerate the fluid resulting in a small amount of air being purge at the reservoir each time it is used. Now the purging time is dependent on the hose that was installed. The Jaguar hose is smaller in circumference resulting in less air in the system. I am not convinced that it is the problem you are experiencing. You said that the pump stopped in the process of the down operation and that does not sound like a pressure problem but it sounds like a sequence or a latch hanging up problem.