Edit: Had not yet seen Sam's post when I wrote this. Much redundancy here.

The thing is ... our rag tops go up and down by way of hydraulics. Either the pump makes too much pressure or the hoses were not designed to handle the pressure which the pump creates (take your pick). In any case, said hoses have a habit of exploding in the worst possible spot ... at the latch above the windshield. A shower of hydraulic fluid follows.

This gizmo, and an alternate hydraulic-based solution keep the pressure in the system from getting so high as to let the hose explosion happen.

There you go.

Now the bad news: since this device has not been granted CENELEC certification, you can't have one. Lucky for you that you have a coupe, huh? It may actually be illegal for you to read about it, so best destroy your computer after reading this post.

 

Sam,
Keep in mind it does not prevent the hose from bursting that is already weakened by the stress of the previous factory pressure of 1600psi. It will, however, extend the life of the hose and seals.

 

Sam,

Please don't forget to order a few extra connectors and pins for those of us that had already installed a resistor.

 

Yep... they are on the way.

 

Hi Ivan,

Glad to see you here! I have learned a lot here and though you have more car knowledge than most, this retro-fix seems to be a good solution for now. Please stay here and offer your Jaguar expert knowledge! A great group of guys(and gals) here!!

 

This seems to be the consensus--that a significant contributing factor is the heat the builds up in the header near the latch. But how hot is hot? I am in SoCal where it is not unusual to get temps in the 90s to 100s during the summer. However, my car is rarely sitting out baking in the sun. At home it is in the garage and during the day at work it is in subterranean parking. Does being in the sun even for short durations cause a problem, or is it really more an issue with cars that sit out all day in the hot sun?


Doug

 

I'm just guessing here, but I think the effect of heat on the hoses is probably cumulative. If you're keeping the car in a cooler environment most of the time, I would bet that the hose would last longer than one that spent all of its time in the Arizona sun.

On the other hand, maybe I'm wrong. You should at least raise and lower the top with the engine off. No sense in taking unnecessary chances.

 

Sam,
I'd like to buy your electric "kit" if you're getting enough parts in for another one. I can send you PayPal payment right away if you send me your account info (I tried to PM you and it acted like it worked - my first attempt as a new member - but when I checked "sent", it didn't show and no surprise, no response from you!).
I discovered the forum through your headrest video, which worked great for me (actually, one still to do). Watched your other videos and my wife came in to see why I was LOL'ing so much. I told her, "There are other people like me out there!". She said, "You're kidding, right?" I especially loved the foul language countdown and the "30 minutes later" and "another 30 minutes later" cue cards (and the fact you could see it getting progressively darker in the garage!).

 

Thanks for the info, Dennis.

 

Hope my clumsy attempt at humor did not come across the wrong way. Sometimes on this side of the pond we poke fun at EU regulation, when there's plenty of amunition for comedy right under our noses.

 

What you said. At the end of the day, we really have no reliable way to predict which particular hoses may fail, or at what pressure. I think it's pretty encouraging though that there have been no reported failures with either form of pressure reduction in place. (Have there?)

 

Just for the time savings of buying the connectors and resistor, and it's the way I'd do it with the proper connectors rather than cutting the existing wiring, I'm well up for it. Thanks to Dennis for engineering this solution and Reverend Sam for offering this premade solution at a bargain basement price.

PM Sent!

 

Thanks for the kind words. An FYI: even for those who might want to "roll their own" there is no need to cut a wire. Test_point developed a method which gets around this. It's shown in the latest version of the system description ... www.scorekeeper.com/jaguar/jaguar01.htm

 

Here is what I think should have been developed--either by Jaguar once they discovered the problem or by a team like Gus/Walt/Sam/Dennis, etc. The latch mechanism/assemblage should have been modified so that a solid metal tube was braised to the latch. This tube could extend to the A-pillar and attach via some fitting to another solid tube that extended down the A-Pillar. The actual connection of the hose could then have been somewhere in the kick-panel below the A-pillar. In other words, no actual hose would be in an area where it would be subject to heat. Also, if the hose needed to be changed out it would be a bit easier since it would only need to extend to the kick-panel and not up the pillar and over the header.


Just a thought.


Doug

 

Hi Sam,

I'd like to get the Voltage Reduction Kit to Reduce Hydraulic Pressure. Please PM me where to send payment. Thanks.

Bassmania

 

Got mine about noon today. Looks good and great workmanship. Fast Ship, Weekend Project coming up, though it should only really take about an hour at the most... Thanks - Reverend Sam

 

Hi Rev Sam,

I too am fairly new to this forum but would definitely like to purchase a harness.
Is this possible?
Thanks much,

Dave

 

An hour! 10 minutes at the most using the Rev's pre-assembled harness. The hardest part is getting the side panel off, which is really simple. I "rolled my own" a few months ago.

 

Actually, pulling the existing connector apart can be pretty tough. At first I thought the plastic connector was just tight, but it's actually the pins themselves. They are like normal spade connectors, and if you've ever tired to pull spade connectors apart you might have noticed how tight they can be. When you're unplugging the connector in the trunk you're disconnecting two spade connectors at the same time. The key is to just jiggle, jiggle, jiggle. You won't be able to pull the connector straight apart. You have to move it from sided to side, pulling it apart as you jiggle it.

Having said that, yeah... it's a ten minute job.

I learned some stuff making this first batch, so the next batch is going to look a little different. Instead of having an 18 inch pair of wires with the resistor soldered a few inches from one end, I'm going to Make the white wire only 2 or three inches long. There will be two black wires, one from each connector down to the resistor. The two black wires will be shrink-wrapped securely. The kit will include a strip of double-sided thermal tape, which will be used to fasten the resistor to the top of the metal rack that holds the CD changer, nav system, amplifier, and hydraulic pump. The rack will act as a heat sink, keeping the resistor cooler. The tape is specifically designed to hold heat sinks to the device that is generating heat, so it's supposed to be able to withstand high temperatures and conduct heat efficiently. I'll post a picture of one before I start making them, and if you are one of the TWELVE people who are on the list to buy one, You can pick between the old style and the new style.

Speaking of the twelve... I originally bought enough parts to make 10 units (it was supposed to be 20, but I screwed up. That's another story) Those 10 were all spoken for in the first day or two. I then ordered enough parts to finish the next ten. I already have 12 people on the waiting list, so I went ahead and ordered parts to make a third batch of ten. If you're one of the people on the waiting list you should have your resistor next week.

Here's the waiting list. If I left your name off please let me know. I've gotten a little confused between user names, real names, email addresses, and in some cases, business names.

JPHAR123
rjag
pophen
DrPerlJam
CatMan
Silverstone
Platinummaker
80sRule
bassmania
and three non-members who emailed me

 

"double-sided thermal tape"

Rev, I ordered one of the first batch. Where might I be likely to find something like this thermal tape locally? A hardware store? An electrician's supply outlet? Radio Shack?