[xj] 1985 XJ6 cruise control

XJ
1

I started to troubleshoot my non-functioning cruise control yesterday, beginning with the actuator. I applied 12V to one yellow wire going into one of the coils, and that appeared to let engine vacuum go to the bellows, so that seems to be OK. Does the other coil let atmospheric pressure into the bellows? Its hard to tell if that’s working or not, but I’ll assume that it is.

I noticed, however that the bellows does not seem to seal tightly to the stationary end plate; you can spin the bellows on the plate with some ease. Is this significant? Does the bellows need a tight seal to work properly? (I assume so since one wouldn’t want a big vacuum leak during cruise operation.)

Thanks for any advice you can offer.

Dirk Roorda

2

Dirk:

“Does the other coil let atmospheric pressure into the bellows? Its
hard to tell if that’s working or not, but I’ll assume that it is.”

I determined that one controls vacuum and the other vents to atmosphere.
One of mine was stuck so I used a little WD40. Presto!

“the bellows does not seem to seal tightly to the stationary end plate”

Apparently, this is normal. However, seems like it would work better if
sealed. So I used silicone adhesive and selaed her up. Now, it holds rock
steady. Of course, if I need to lubricate the solenoids again I’ll have to
scrape off silicone.

Mark Revels
85 XJ6