I have a 1999 xk8 convertible. when putting the top down the motor wines but not when it comes up. any thoughts

 

I've never seen this, does it take longer for either cycle? Is the whine continuous (not just priming the pressure)? Is there any chance you can just plain hear it better from the cabin with the roof up? IOW, is it the same noise issues outside the car opening / closing with the key in the driver door?

If you are going to check the fluid levels don't forget you will see a very different level with top up vs. top down.

 

all the doors and locks work fine it just the hydraulic motor makes a winning sound when the top first unlatches and starts to go down after it get about half way down the sound go's away, every now an then the motor will just wine and nothing will happen. Then If I wait a minute or two it will start to work but still with the wine.

 

What colour is the fluid?

Please post an intro in the new members section when you can.

 

Check the fluid level in the reservoir it should be at the top embossed line on the tank. Your being a 1999 you should have the new fluid in it and it should look a little green in color.

Link JagRepair.com - Jaguar Repair Information Resource
Link http://jagrepair.com/images/AutoRepa.../IMG_1316w.jpg

 

My car has the same whine and for the same time. I hear it as I stand outside the car, engine off, and using the key in the door. It does not make noise when top is raised. I haven't checked the fluid yet, as the top seems to be operating correctly.

 

Here's a couple of thoughts. Mine whines in the same manner as most describe but is really different with temperature.
I live in Canada and the top latch won't open below 15deg C (60F). I don't know if this the fluid or a safety feature but it won't open till it warms up. The colder it is the louder it is.
Here are the noise patterns, opening roof, latches and initial raise louder, half way when the weight is off the lift rack it goes quiet.
Closing roof, initial raise to half way louder, then quietens down until latches move to lock then a little louder again.
Hope this helps.
BTW, I would recommend you get out the manual and actually unlatch and lower your roof by hand and raise it again and lock it. May come in handy one day and it's easy to do.

 

Skooba,

There's no temperature cut-off for operating the latch. It should work even around freezing temperatures. If you have the old "brown" fluid in there, that would cause what you're seeing. Or things could need lubing.

I believe the whining that people are describing is probably the sound made by fluid flowing through the pump's internal pressure control valves (if not caused by low fluid). Long story short, pressure rises when the pump is having to work hardest in moving the latch or top mechanisms ... pretty much at the times you described. The pump has internal valves which open as needed to keep pressure below certain limits: about 1600 PSI during latch operations, 1200 PSI during top operations. These valves, when open, spit fluid directly back into the reservoir and there is a sound associated with that.

The two valves are visible as the little cylindrical thingys mounted on the pump body in the photo below.

 

Thanks Dennis,
What is the name or type of the green fluid?
I would like to get some.
Mine is the brown.

 

Pentosin CHF-11S, about $20-$25 for a litre (more than enough)

 

Skooba, a search here should turn up procedures for purging the old fluid, which you'll want to do when switching over to the CHF-11S. This newer fluid flows much better than the old stuff at low temps.

 

Post #5 has a link for the type fluid. Unless your car is a 1996 to 1998 you should have the correct green fluid.

Gus
www.jagrepair.com

 

Dennis and Gus,
I just chimed in on this post thinking I might help out a little and in turn received more help than I offered. I love this forum. New rule: read all the posts!
Thanks guys.
Gus, mine is a 1998. Should I still change to green? I should flush it anyway as it is probably the original fluid.

 

Yes change to green the older fluid can gel.

 

Thanks!

Gus
www.jagrepair.com

 

Yes I would recommend replacing the old fluid. If you elect to invert the tank to drain it I would recommend that you use caution in doing so you do not want to bend or pinch the hoses. If it were me I would siphon the old fluid out of the tank refill it and operate the roof a few times then remove that fluid and refill the tank. After another few operations change the fluid again and you should be good to go.

 

Roger wilco
Thanks all

BTW
got one month tops...then snow...summer jaggin is the best!