I have only owned the car four days. I operated the top with no problems the first two days with one exception. The latch in the windshield header did not retract when the top was fully down (I just think it should) and I had the error message that the hood was unlocked. The previous owner said that was normal, the top couldn’t be locked because it was down.
Other than the latch sticking up everything was normal. I operated the top from the console button, the door key and even while traveling at low speed.
Now it fails to work, the rear quarter windows drop and I hear a hum from the trunk area that I assume is the pump operating for about 10 seconds, it shuts down and then nothing. The rear windows operate normally with one touch of the button.
The hydraulic fluid is just slightly low, maybe an 1/8" below the low line. I have un-latched and re-latched the top manually, I get the proper “hood not latched” which clears upon re-latching. I have tried unhooking the battery for ten seconds.
Any suggestions will be greatly appreciated.

 

If you give a slight push manually while operating the button does anything happen?

Doug

 

The system is quite sensitive to having the correct fluid level. Fill it up so the level is between the two embossed lines.

 

Check the fluid level.

 

Check the weblink below Gus' signature in post #4.

You'll learn a lot about the XK8 convertible top there.

Graham

 

Fluid level is critical, even a little low will not allow enough hydraulic pressure to operate the system. The fact that you stated that the actuator was not retracting would lead me to believe that low fluid is the culprit. Fill it up and then operate a few times to bleed system. Then check whole system for leaks.

 

I’ll certainly try topping off the reservoir. I have a question about the correct hydraulic fluid to use. What I see on the forum is Pentosin CHF-11S but I also hear about the leaks being green. Mine looks yellow through the plastic reservoir.
If I can get that straightened out, I’ll fill it up and report back.

Thanks for the quick replies.

 

Also, do not run the pump for a long time because it can easiily burn out on low fluid level. The top pump is inside the cover near the 6 disc CD in the trunk near the Nav CD. The start/run capacitor on top gets hot if the fluid is low. Also, it is not uncommon to burn out the fuse. I had the pleasure of burning out my top pump and discovering JAG and its supplier were having a renegotiation, and it took me 3 months before my top was down again (yes, I know about the Allen Key method of operation, but couldn' bear the humiility of it if any Porsches were around).

 

Mine is doing exactly the same, but mine is due to the latch mechanism being almost siezed, once everything is released as it says on Gus's website I can barely undo the catch.

Not a 100% sure why this has happened as of yet as I have not had a chance to pull it all apart, not a usual case!

 

The very early cars used a yellow fluid, but it was revised to the green Pentosin well before 2002. It is possible someone replaced your fluid with the incorrect one. It may be best to change it out completely and put in the Pentosin CHF-115. One liter should be all you need.

 

I seem to forget the proper fill procedure. Is it up to the second line in the reservoir with the convertible top closed or open?

 

Upper line, top down ... lower line, top up.

Also ... For Gary Jackson ... another usual suspect is the petcock located on the pump body. Make sure it is completely closed ... i.e. turned clockwise.

 

Sorry to mislead everyone with the "yellow" fluid. That was the way I remembered it. So much for my memory! I removed the cover today, I can't say that it is green but it is dark and I assume green. I'll have to order the fluid so it will be awhile before I know if that helped. I will let you know.
I appreciate everyone joining in this thread.

 

Your local NAPA auto parts may have the fluid in stock.

 

I've moved all the posts discussing the reservoir level to a separate thread so as not to hijack Garys thread.
Anyone interested can find it here https://www.jaguarforums.com/forum/x...cussion-77944/

 

Along with AutoZone, PepBoys & Advanced Auto

 

Well, I have the fluid level topped off and still have exactly the same problem.

I have found a problem that I wish I hadn't. I lowered the top manually and found out that it doesn't make any difference whether the by-pass valve is open or closed! IF the pump is moving fluid, it is bypassing somehow and I can't believe the by-pass valve is leaking through. I see no evidence of a leak anywhere in the system.

Help please.

JFI, Auto Zone and Advanced Auto did not have the fluid and couldn't order it, Napa didn't have it in stock but did order it for me.

 

Check your PM.

 

Go to info@justanswer.com and you can ask Richard, and request him- he is an ex-Jaguar mechanic and shop manager with 13 year's of experience and he has been very helpful to me. His questions cost $29.00 or so, but are thorough, and he has all the manuals.

 

Does he give you a refund if he's wrong?