Am putting a new bellows in (URO, which won’t air seal without some ‘help’!) and would like to know if the cable is hooked up with the bellows at rest–or extended?
Thanks.
Thon
87 XJ6
Thon,
I have removed more than a few cruise control actuators from my Jaguars, removed and replaced the cracked rubber bellows, reinstalled the rebuilt actuators in the cars, and restored their proper operation. I use cruise control regularly and fix it right away when I discover that it isn’t working.
I seal the metal plates at the ends by putting a bead of clear silicone sealant in the grooves at the ends of the rubber bellows, inserting the metal plates (remember to install the spring before doing the second plate), and rotating the plates into their proper orientation. Then I wait overnight for the sealant to cure before installing the actuator in the car.
When I reinstall the actuator assembly back in the car I first attach the ferrule and screw to the cable with the bellows extended before attaching the actuator to it’s mount with the bolt. When mounted back in the car I make sure there is a small amount of slack in the cable when tightening up the cable adjusting ferrule and screw. If the cable is too tight you will notice that your engine RPM is too high because the rubber bellows will be pulling on the accelerator. Once the bellows has been exposed to engine bay temperatures for a while the rubber softens and extends a bit and you might find that the cable is too loose and in need of a little adjusment.
I hope this answers your questions. If not, let me know.
Paul
I’d offer up some help, but all I know is that out of the 7 Jag’s I own, only 1 (the XJR) has a functional cruise control.
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No vacuum, fully extended, Thon - Paul’s description to be followed. And don’t lose that ferrule…
Frank
xkj6 85 Sov Europe (UK/NZ)
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Thanks Paul.
Frank–you’re confusing me. 
“fully extended” would not be ‘at rest’, which is how I read Paul’s instructions, i.e. some slack in cable.
You mean the ferrule and screw I had to buy, as they were missing on this car? 
Thon
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Indeed, Thon - I should have said ‘with the actuator fully extended’; the actuator is fully extended ‘at rest’…
I usually work on the actuator in-car, but however you put the bellows on; the actuator will settle ‘at rest’ when assembled properly. Incidentally, no sealing was used ex-factory with new bellows…
And the ferrule, clamping the wire with the screw, ‘usually’ is lost by the unwary - as nothing is holding it when the wire is released…
Frank
xj6 85 Sov Europe (UK/NZ)
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Hello Paul. I’m in the process of getting my CC working in both my 1990 Series 3 V12 Vanden Plas and my 1991 XJ-S Classic Collection. I see that you also own both cars, as well as a couple of older classics.
In your post, you mention that the end plates must be oriented correctly when you seal the bellows with silicone. I’m wondering what you mean as I’m not sure it matters. I’ve sealed the bellows, but the CC is still inoperative. It could be a number of things of course, but I just want to make sure I have the bellows set up properly as a starting point.
Any help would be much appreciated!
Thanks.
Steve
My guess is that was just with respect to putting the cables/connections in the best orientation for hook-up.
It would occur to me. Apply vacuum, bellows pulls the cable. Cable pulls gas pedal down.
My Jaguar’s bellows never got reinstalled. I am not a fan of CC.
Frvades ago, i installed an after market unit in my 79 IHC scout II. A metal can with a diaphram as the bellows. And a small chain to pull the throttle linkage.
Other cars use a step motor to pull the linkage…