First off, I have spent the last few days searching the forum and reading on how to operate the top. While there are a lot of questions and answers on temporary fixes (capping the pump ports) or using the pump to control the top but manually latching it, I haven't found much on stripping the entire system or permanently changing it. I've also seen people on here wanting to change it from a hydraulic to an electric controlled conversion. Before I hear the purists or naysayers come in and ask "Why?" or go into a resale value debate, these are more or less hypothetical questions and open for discussion. I am also looking to see if any have gone completely to a manual system and/or stripped it, and what you like/dislike about it.

From what I understand, when people cap the pump ports, they only cap the two controlling the latch operation. There are a total of six lines (2 to latch and 2 to each ram) from the pump, all with a push type operation. I haven't read anything about disconnecting the rams themselves. I believe this may lead to easier manual top operation due to no fluid or air flowing through it, but it may also have detrimental side effects due to not completely locking. I just drove my newly acquired XK over 1000 miles, and the top pump is inoperative. I have no reason to believe the rams ever locked anything in place before the trip, as I manually lowered the top without having to physically unlock them after I arrived home.


I realize it is better to leave some fluid inside the lines to prevent them drying and cracking. I also think I understand the cons behind leaving fluid or air in the convertible hydraulic lines. It is much the same as disconnecting the power steering pump and running a steering rack with fluid left in it vs bleeding the system...bleeding the system makes it easier to turn from side to side due to not having to fight against any existing fluid by forcing it through small valves.

My questions:

Are there any members here using a completely manual system for the top on a regular basis (manual latch AND manual raising/lowering)? Did you strip the car of all lines and pump, or did you leave them in for later use?

2) To use the top completely manually, are there any side effects from not completely locking the hydraulic rams? From what I've read, one needs to reach behind the top to manually lock them, as they do not lock simply by hand raising the top and latching it. By not reaching back and locking them would you need to worry about play or slop in the top while driving, long term?

3) Would completely bleeding the system and disconnecting the lines be detrimental to the rams holding the top up when not locked into place? For instance, even if you let the lines drip into a bottle, there is still some fluid in the lines and you are potentially still fighting it by pressing it through any lines or valves that may be in place, especially around the hydraulic rams. When you manually raise and lower the top with fluid in there, there is a certain amount of resistance to moving the top due to moving fluid/air inside the lines and valves. Would this fluid inside help keep the rams more rigid when the top is up when the rams are not locked?

4) By disconnecting and bleeding all the lines, would the top not be slightly easier to manually raise/lower?

5) Can you remove the rams and still lock the top? I realize it would be difficult and inconvenient, but I am assuming the rams only push the friction/spring lock into place, and you could hypothetically remove the rams while the top is locked and it would not come unlocked because the rams only push it into place to lock, but do not do any locking on their own.


As a last question, for a manual operation with the pump capped and lines disconected from it, I understand one needs to 1) unlatch the top with the allen key 2) push the top down button 3) roll down the rear windows (if they didn't auto roll down) 4) push the top down.

Is there a way to do away with the need to push the top down button (I am in the process of placing a separate power window switch for the rear windows on mine anyways)? I am not electrically inclined by any means, but is there something you could place in line in order to do away with the need to press the button and a possible dash message lighting up?

I may not have the entire theory pat down on all of this, as I just bought the car. I'm only going off of the little experience I do have and the reading I have done here. Please feel free to correct me if I am misinformed on any of the above.

Thanks all!

 

If you want to manually raise/lower the top you can just open the pressure relief valve on the pump. I did that when I replaced my hoses and I could easily lift the top. I see no detrimental effect on the hydraulics in doing so. I would just leave the system in place.

I would consider that a major PITA if I had to do that all the time. I had an old corvette that required manually lifting the top and I loathed doing it after a short while.

 

Thanks for the reply, rothwell. Perhaps I wasn't making muself clear. I'm not worried about any detrimental effects to the hydraulic system itself. Also, when opening the petcock and releasing pressure, there is still plenty of unnecessary resistance when manually moving the top because you are still pushing fluid around the lines and valves.

I don't plan on having the top open all the time, even in the summer. I'm sure in Florida you get quite a bit more use out of it year round.

 

You can operate the roof manually but you should lock the roof up to prevent any damage to your windows. The rams supply extra pressure to the rams to lock the roof linkage that prevents the roof from bouncing. I do not know for sure that the linkage would lock without the rams it looks like it could but I do not know for sure. I never tried it. Are you asking this because of ram or hose failure to the rams?

 

The pump/motor is out AFAIK. I haven't really done any trouble shooting. When the top down button is pressed, it will chime, rear windows roll down, but nothing else happens. Pressing the top up button doesn't result in anything. I thought maybe it was out of sequence and I tried it a handful of times but couldn't get any of it to work. I had to pull the relays in the trunk and jump them to get the windows back up. I also checked the fluid level and it is fine.

Today I bought the caps to plug the hoses going to the latch. I figured if I did away with those hoses why not the rest? I'm not opposed to raising and lowering the top the way it was done back in the day.

That would make sense with the windows and seals, though I wonder how much it would really affect them. I can't get it to really budge with the top up. I thought I had seen someone post on the board a while back that they, too, were working the top by hand.

 

If the pump appears dead, there may well be a quick easy fix.

Open the big two-pin connector leading to the pump and apply power --- just for an instant --- directly from the battery to the pump using test leads. Either polarity is OK for the test. You'll hear it if it's alive. If not, see "motor repair" in my sig. line below ... likely to be a cheap noise-suppressor component that's bad.

 

Okay, I poked around a little today. First I added a rear window switch and spliced into the wires underneath the arm rest as instructed in this thread (picture also attached)...

https://www.jaguarforums.com/forum/x...n-37826/page3/

Well, the window "down" side of the switch works, but I cannot get the rear windows to go up by the switch. I switched the wires around on the switch terminal to see if the switch was bad, but it's all good. I also took off the quick clamp splice and reseated it in case it did not get a good connection, but still couldn't get the rear windows back up. Infact, I cannot get any sound whatsoever when I click the switch up.

The next thing I did was check the window relays in the luggage compartment. I know I could pull the relay and use a jump wire to roll them up, so I know the window motors are good. I switched the relays around for the "up" and "down" but I still could not work the windows up or to make any sound...while the down continued to work.

I then realized the fuse for the top was only a 30 amp instead of a 40 (also attached picture), plus it was clearly blown. I replaced that with a 40 amp fuse and visually checked all the others. I then checked to see if the windows would roll up by the new switch and they would not. Again checked the 40 amp fuse and it was still good. I then attempted to bring the top down by the switch. I toggled it up and down a few times with no luck and went back and the 40 amp fuse was blown.

What I do not understand is why the rear windows will not roll back up by the freshly installed switch? AFAIK it should be completely independent of the top. I don't think the microswitch in the top (sensing if the rams are not locked) will thwart the rear window switch from being used. I can replace a couple of 20 amp fuses for the window lift system in the trunk and see if that works, but if they go down fine by the switch I don't think that is what it would be.

Also, I'm still supposing there is something wrong with the pump motor, blowing a fuse and all. I will try your check method soon, Dennis07.

Here is what happens (or doesn't happen) when I press the top down button. The chime sounds and the rear windows go down. The front windows go down just a little (as much as when you open the door) and then everything stops. Nothing happens with the top.

When I'm at this point I can then press the top up button and no sound comes from the rear windows or trunk (that I can hear), but it will cause both of the front windows to roll all the way down. I don't know if this last check is a fair assessment as the top is then out of sequence, but it is odd the front windows roll all the way down.

 

The pump motor blowing its 40-amp fuse is a pretty good tell. Very likely you've got a bad transient suppressor in there. Cheap and easy fix.

It's hard to trouble shoot the other bits without confusion while the pump motor is in trouble, and it might just be that nothing else is bad.

 

Good point. I just went ahead and ordered 5 TVS diodes off of Amazon, ended up being almost $13 with shipping. It sounds like some on here were getting them cheaper, but when I checked Ebay they were about the same price, and the other sources I checked were either the same with shipping, or they wanted you to buy in bulk (sorry, I don't think I need 2,500 diodes right now).

I'll try and get the window switches sorted after the top is fixed. Thanks for the help so far, that write up is awesome!

 

You're quite welcome. I think there's a decent chance the window issues will sort themselves out once the pump is working, and the system figures out where it is. May require a hard reset, but maybe we'll be lucky and things will just fall into place.

 

Dennis07, thanks again for your help! Just pulled the top pump motor, disassembled it, and sure enough, the TVS diode inside was split right through the middle. I soldered in a new one outside the motor body (as explained in your how to) and pulled the old TVS diode out. Did some very light cleaning inside, put it all together, and replaced the 40 amp fuse. Voila! Top now goes up and down as it should, along with the windows.

Now I get to trouble shoot the new rear window switch. It still displays the same symptom, which is weird. I will admit I did not play around with it much, as I lost daylight. But with the top up the new switch will roll down the rear windows, but not roll them back up. In order to get them back up I can press the top up button and they'll roll up. I'd still like to figure out why the new switch will not roll them back up. I'll report back with more info when I get a chance to play with it more. In the mean time, if you guys have any input, fire away!

Aaand for the pictures of my TVS diode install....

 

Hello, I am new to this forum... I have enjoyed reading about this post regarding the convertible top. I have a 1997... not sure how different mine is form whats being describe here... I would be happy to just go to a manual operation... my system stopped working and even the dealer could not fix it ....after close to $800 I pulled the plug. If I just open the pressure relief valve on the pump as Rothwell advised.... is that it? I do not care if the rear windows are up all the time... but I did see some talk about getting them to run up and down... my 97 has no rear window switch... its part of the top up/down mechanism. Maybe there is a way to use the top switch to just run the windows :-) Last thing... I assume that I need to latch the top back into place with the alan wrench near the rear-view mirror... which is fine. Thanks so much... I look forward to being a part of the forum....I'm also a 60's era muscle car guy :-)

 

Welcome to the forum Margozzi!

I'm curious as to what the symptoms are to your top not working? What happens (or doesn't) when you press the roof up/down switch? The nice thing about these cars is how "rebuildable" they are. Instead of thowing new disposable parts in, many times you can disassemble and replace just the small part that may be broken or malfunctioning.

You can raise and lower the top manually with all the lines in place, but it requires you to open and close the petcock, which gets a little annoying after a while. My original questions and intent of this thread was the feasability of complete manual operation by doing away with the hydraulic lines.

As for instructions on the rear window switch operation, here is an excellent thread on the topic...

https://www.jaguarforums.com/forum/x...op-down-37826/

 

chillyphilly,

Paul Margozzi here... Thanks for the reply....

ok, so the story on this is that one day the top went down like normal....but when I went to put it up using the switch.... the top did not move and the rear windows stay down.... no sound ... nothing. I checked the fuses etc, but no joy. I manually raised the top and latched it. Took it to my local shop and they fussed with it for days...I finally said... look... just get the windows up and we will call it a day. Its been this way for a couple years now. I don't dare open the top because I assume I'll have the same issue.

I am fine to just manually open and close the top like the C3 corvette... I don't need the pump to work. Actually when I purchased the car I just knew that this would be the first thing to die... and it almost was ;-)

So is it possible to just leave the pet **** open all the time and call it a day? Or do you need to do more... why open/close all the time? I would assume I need to drain the lines first ;-)

I'll check out the thread you sent on the windows... that will be great to get working isolated from the top functioning with the top switch.

Thanks so much,

Paul

 

If the pump did not operate when you attempted to put the top up and the fuses and relays were good then I would check to see if the pump motor has a problem like ChillyPhilly. Just know that that the windows will not operate closed until the rams for the roof are fully extended and locked. The roof fully closed and locked prevents the roof from bouncing adding stress on the windows and linkage for the windows.

 

My top showed similar symptoms, with the exception that my 40 amp trunk fuse kept blowing. When I'd push top up, nothing would happen. I agree with Gus, it is worth looking into your pump motor. It is simple to take out and open up. My TVS diode fix only cost $2, and everything works as it should now. Before you do that, obviously check if your hydraulic fluid is low. That can stop the top from operating if low enough.

Here is another thread regarding raising and lowering the top manually. I believe in order to eliminate the possibility of frame damage to your roof and any error messages on your dash ("roof not latched"), you must open and close the petcock at different times to keep the system in sequence. If I am not mistaken you can disconnect and cap the latch hoses and then you may be able to bypass opening and closing the petcock each time...I'd have to re-read it though, I've been busy sorting through other issues so I don't fully remember.

https://www.jaguarforums.com/forum/x...eration-89085/

As an aside, I managed to fix the window switch. One of my crimps on the connector was not any good. I re-ran wire and a new connector and now I have rear windows that work independent of the top!

 

Take one step at a time.

It is my understanding that the roof operation was looked at by a mechanic and that the pump/motor is not working. If that is the situation then be looking at it and power to it. Capping the hoses is a process to eliminate the hoses to the latch for manual operation and allowing the pump to control the roof rams. The petcock will redirect the fluid in the entire system to free flow in other words to allow you to move the roof and latch manually if the pump fails. Attached are links from my page that might help you better understand the system.

Link JagRepair.com - Jaguar Repair Information Resource

Link JagRepair.com - Jaguar Repair Information Resource

 

Gus, I read the docs you posted... very cool...thank you for having the drive to do this for us and taking the time. I'm an engineer as well so I enjoyed the data. I generally work on older cars and use many tools...however I have never used a lap top to fix my car :-)

Luckily my XK8 has never had the green shower... no hyd issues. I also was told the same BS about the gelling of the fluid in the lines...in any case. I think what I need to do is check the system now that I have a road map of the hyd and electrical systems in play and make sure its all as it should be and go form there. I wanted to go to full manual because there did not seem to be a better solution. Too much in play and no information.... now I have the information ... and I love to fix things :-) Thanks so much Gus and thanks to you ChillyPhilly

 

While I decide on what investment I want to make in terms of new hoses, I decided to use the manual method Dennis07 links to.
I printed the instructions (easy) and put in te glove box for easy reference.
I capped the hose ports in the back using the fittings that dennis suggests. A local hydraulic shop had them for just a few bucks.
I didnt like the look of the hole near the visor so I purchased a small plasic trim insert with a hole in the middle from the hardware store. I then cut a short section off an allen wrench and glued it in the mechanism using rtv (removable in the future). The allen section sticks out 3/8 of an inch.
I keep a long 8mm wrench in the glove box to use on the allen segment. It gives more leverage and it has a more finished look than just a hole.

 

Nice touch!

And surely easier to use than fishing the Allen key in there every time to find the latch mechanism.

If you don't mind, I'll add this to the write-up you referenced (with attribution of course).