Cruise Control Problems

[RS23VOA]

Hey guys.
1970 Challenger
Trying to figure out why my cruise control isn’t working. The solenoid clicks when I turn it on and clicks when I hit the “set” button but it won’t hold. I have a new diaphragm and have good vacuum. I’ve run a ground wire from the - on the battery to the CC unit and it didn’t help Anyone had this experience they can help shed some light on ?

 

[sixpactogo]

If the cruise kicks in but slowly loses speed, the diaphragm is losing vacuum somewhere. If it won't start at all, it could be any number of reasons. Even a brake light out or a bad connection.

 

[EV2RTSE]

New diaphragm for the servo? Would be interested in hearing more about that. Sorry no help on your problem but following along as my car is N88 equipped as well. Hopefully when the time comes I have a good working servo out of the ones I've accumulated over the years. So far I've done the click test on them too but actually using one on a running car is another matter.

 

[Challenger RTA]

I seen this a few days ago. I forgot to look if there is a filter under the cover. Bad or blocked. That will keep it from working.

 

[Ronbo73]

Hey guys.
1970 Challenger
Trying to figure out why my cruise control isn’t working. The solenoid clicks when I turn it on and clicks when I hit the “set” button but it won’t hold. I have a new diaphragm and have good vacuum. I’ve run a ground wire from the - on the battery to the CC unit and it didn’t help Anyone had this experience they can help shed some light on ?

I am in the process of troubleshooting my cruise unit also. I am retrofitting mine onto my 6 barrel setup. Where did you get a new diaphragm?

 

[Old Mopar]

cruise works on a six pak only if you install a lost motion link at the carb - I have only ever seen one ctr 6 pk carb with the hole for the lost motion link. I have seen cruise on a six pak where the hole for the lost motion link was added - carefully.

As for the OP those servos are pretty reliable - they typically work or they don't. You can check the integrity of the servo diaphragm using a vacuum pump.

 

[Ronbo73]

cruise works on a six pak only if you install a lost motion link at the carb - I have only ever seen one ctr 6 pk carb with the hole for the lost motion link. I have seen cruise on a six pak where the hole for the lost motion link was added - carefully.

As for the OP those servos are pretty reliable - they typically work or they don't. You can check the integrity of the servo diaphragm using a vacuum pump.

Hello Old Mopar. My car was originally a 318 2 barrel w/cruise. I saved the carburetor with all linkage from the manifold and I do have the lost motion link. I made a bracket to connect the cruise cable to the throttle linkage. I'll post a picture of it on the carburetor tomorrow.

 

[Ronbo73]

Cruise unit with lost motion link on attached to the center carburetor.

 

[RS23VOA]

I am in the process of troubleshooting my cruise unit also. I am retrofitting mine onto my 6 barrel setup. Where did you get a new diaphragm?

Email this guy. Bought two from him but my original looked fine when I pulled it out. They were $50 each.
nooalf@aol.com

 

[Old Mopar]

That is an interesting adaptation of the lost motion link.
Does the cruise control "control" the speed properly?