This Site is a tremendous help to me so want to post thisin hopes it will help another . What happened was I was rolling with top down,hit roof up button half way through this I stop car , stopped movement of roofby taking finger off button ( this was the mistake ) , put car in park andcontinued to close roof , roof cycled 90% closed to the point where the latchedgrabbed the hook on roof but never pulled it fully closed and rear windowswould not go up . I tried many fixes , manually locked roof , checked all fuses, fluid , check open and close switch on console , tried to disconnect batteryto reset , all with no luck . I tried to manually open the top but feltresistance and couldn’t figure out why although I had the petcock open todisengage the hydraulic system, Than sent Gus an email and he suggested maybeone of the rams never fully lock and bingo that was it , one was fully extendedlocked (reason I could not manually open roof ) and one almost there but notfully locked causing the system to shut down . Fix- manually unlock latchedwith hex key , open petcock ( counter clock wise ) climb into back seat reachinto the compartment between roof , wheel well and inside roof liner , you cansee the pistons and rams , I applied pressure to the top of ram with my handwhere it meets the rams hinge and I felt it give . folded roof back to fullyopen position , locked latched with hex key , closed petcock ( clockwise).Disconnected negative battery terminal, put key in ignition turn car onpressed horn to bleed any electricity left in system lit it sit a few minutes ,reconnected battery and pressed roof up button and Viola roof closed and rearwindows shut ! Thanks a million Gus !

 

Thank you forum informers & collective intellect.

I have never heard of petcock before and i just was alarmed at the latch not latching in this 99 xk8.

I have torque wrenches and am going to google & youtube for where the petcock is located to manually make adjustment for this to be correct.

Level of danger & damage to driving at speeds of 40 mph with latch not latched despite the top seemingly meeting roofline & A-pillar.

Any help is greatly appreciated.

Genuinely - thank you Gus as well,
-Nick

 

The petcock is located on the pump it is the T handle on the side. What exactly is you roof not doing?

 

Hi Gus,

Thank you very much for response to my question & asking.

The roof appears to be closed & latched but the sensor alerted that the roof hasnt latched.

Thanks again!

Genuinely,
Nick

 

Take your Allen wrench and try to close the roof latch manually if that does not clear the problem you might have a switch out of adjustment or a bad switch.

 

Gus, I was replacing the rear window regulator on my 04 XK8 convertible when I was sufficiently along to put the top up and see how the rear window closed in preparation for adjusting.
During R&R of the Rear window/Regulator I had the battery ground removed, the hydraulic pump petcock open and the roof partially opened in order to get the top attaching arm loose to aid in getting the regulator out.
Regulator installed and the top attaching bolts replaced, top manually down. I connected the regulator electrical connector, closed the petcock, attached the battery ground, key on, nothing out of the ordinary, started engine. Let it warm a bit then pressed the top up switch. The top came up but would not latch and I got the warning light for it. Shut it down, looked at latch. It appeared the top's metal loop hit the outer arm of of the latching mechanism on the outside edge versus in between the two arms.
I disconnected the battery ground, opened the hydraulic petcock and tried to open the roof manually...no joy, but got it up enough to put the top's metal loop into the right portion of the latching mechanism. Closed petcock and connected ground. Started car, pressed top up...nothing, waited, then pressed top down...nothing.
Do you think I have an issue with one of the hydraulic rams latched and the other open?
Thanks, Frank

 

I manually latched the roof with the allen key and still nothing from the switch, either up or down with the light still on in the dash.
Put the front windows up and hit the down switch and both front windows go down.
Cheers, Frank

 

Was the regulator that you replaced on the right side facing forward if it was I would be checking the connection on the right roof ram. The roof not opening with the petcock open and the latch not engaged tells me that the roof rams are fully extended and may not be getting the signal from the rams.

 

Yes, the passenger side regulator was replaced. The Hyd Ranon that side is up and "locked." The driver side Hyd Ram I can compress slightly by hand (roof latch unlocked as far as I can move it). The Hyd Pump petcock release is fully counter clockwise. The battery is connected.

How do I get the passenger Hyd Ram to "unlock"?

Thanks Gus. Cheers, Frank

 

Be sure that the petcock is open then push down on the ram linkage from the top of the ram piston. Once that is released you should be able to open the roof with 2 fingers, whatever you do do not force the roof open. Once you do that check that the 2 leads to the ram on the right side are attached to the ram.

Check your PM

 

Gus, peacock is full counterclockwise, has been for 6 hours, Ram piston will not budge. Can I use a rubber mallet or is there a way to release the pressure by loosening a Hyd line covered with rags?

I'm quite familiar with high pressure hyd systems having been a pilot/maintenance officer on Army Attack Helicopters for most of my 30 year mil career. The Apache's system is 3000 PSI.
Cheers, Frank

 

The ram is attached to the roof linkage and when the ram is fully extended it locks the roof linkage so that it does not spring or move with road obstructions what you want to do is unlock the linkage.

This photo should help http://jagrepair.com/images/AutoRepa...oof%20Rams.jpg

Do not force or bend the linkage you will not be pleased with the results.

 

Thanks for the photo Gus.
Since the rear seat and all the panels were still out I removed the three 10mm bolts that secure the top's rotating arm mechanism and then pushed the ram up the piston and then pushed down on the top per the diagram you sent and it released with very light pressure.
I lowered the top by hand, stopping midway to re-install the 3 bolts. Lowered the top completely, pushed the latching mechanism back into the upper windshield rail, closed the Hyd Pump pressure release valve and started the car. I let it think a bit, noticed that the red light was out and the caution on top not latched was gone also. Pressed and held the top up side of the switch and the top functioned like normal.
However, the driver's rear window came up fine but the passenger side did not. This is the regulator that I had rebuilt and installed a week ago. I will check fuses today and make a couple electric pigtails to use a 12 volt batter to induce the window to raise. Should have done that prior to putting the top up. Too happy to get that issue out of the way. The electric connector was together. My better half is not here so I'll got it alone until she comes back. If it works w/an external battery (electric connector apart) then I will see if I can find out why it isn't going up with the car's electrical command, if it is at the connector at all. I hope it is just a fuse. Will let you know. Cheers, Frank

 

I am having a related problem, I think. My 2003 XK8 convertible in the last couple of days will not finish closing the top. The header latch will not pull the top down all the way to the windshield header. It stops about a half inch from closing. If I push the top up side of the switch again, the roof will finish closing. I also noticed that, while on the way up, the roof seems to be closing slower than I am used to. I have owned this car for a little over two years, and until now, the top was about the only thing that hasn't given any trouble. Any thoughts?

 

A few preliminary checks ...
- Be sure the petcock in the pump body is fully closed (turned clockwise until you feel it bottom).
- Be sure the fluid level in the pump is OK. Referring to the two hash marks on the reservoir ... level should be at or above the lower line with the top up; at or below the upper line with the top down.

Do you know if there is any pressure-reducing device (a resistor or a relief valve) installed on the pump?

 

I'm certainly no expert on this car yet, but I would also check the battery and its charging circuit.
Let us know what the fix ends up being.
Cheers, Frank

 

Hey Dennis sorry it took so long to reply. The fluid level only changes around the lower level mark, with the top up the fluid is just below the lower mark, and with the top down it is just above the lower mark. The fluid never hits the upper mark. As far as I can tell there is not a pressure regulator installed. I also don't know if the fluid has always been like this, since I never thought to check it when I bought the car. Should I add fluid to the reservoir?

 

The two hash marks on the reservoir represent upper and lower bounds. We want the fluid level to stay between these marks under all conditions ... top up or down. (The amount your fluid level moves between top up and down sounds normal.)

Since your level is sometimes (top up) below the lower mark, you should add some fluid. Filling to the midpoint between the marks, top up or down, would be OK.

I don't know if this is the source of your problem, but just maybe. This system is famous for being fussy about fluid level. Let's get the level right for starters and see what happens.