I have 2 original cruise control units that have stopped working - one on my 77 Ramcharger, and one on my 79 Aspen wagon.

These are original units and I have gone the service manual procedure of checking for vacuum and checking the wiring and the fuse and electric / relays seem to be working as per the service manual recommendations.

The problem is they do not hold speed whatsoever when you turn the unit on and set a speed.

I am guessing there is something wrong inside with the diphragham?

Any help is appreciated!

Pics of the Units below. (notice that these have the bolts around the outside unlike the mid 80's up units which appear to be sealed.)









Greg

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http://www.youtube.com/hyperpack

Years ago we had a new 76 Cordoba that after driving a few winters its cruse control would act up. Sometimes it would refuse to engage, or when in use the car’s speed would start increasing aggressively over set speed, and not respond to stock mounted controls.

I discovered corrosion on the plug connections to the unit. Once the connections were cleaned, the device would operate as designed, and respond to control stock. This cleaning became an annual spring event.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

WJAJR,

I have already experienced that problem. all terminals are cleaned and The Unit gets current and info when it's supposed to.


Thanks for the help,

Greg

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http://www.youtube.com/hyperpack

I don't know that I've ever seen rebuild instructions for one of these. Seems to me you're going to have to open one of them up and carefully examine it to see if you can spot obvious points of wear or damage, and proceed from there.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

That's what I thought might have happen; I just wanted to see if i could pick anyone's brain on these before I do the tear down.


My guess is a leak in the diaphraghm that contols the throttle position.


Greg

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http://www.youtube.com/hyperpack

Often there is a small "snap" switch that goes bad. It is the one that regulates the speed (weights press against it). It has two small flat beams on each side of it that break-some times they break off. Carefully open up the diaphragm area over a clean cloth or paper and look to see what falls out.

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50 chrysler,54 Plymouth, 64 Valiant conv 4 speed, 66 Valiant V8 wagon, 70 Challenger R/T 440+6 conv 4 speed,80 Colt, 98 Neon ACR,84 Honda V45 Magna
Taking care of 57 300C conv,48 T&C conv. Missing my 67 GTX and 36 Ply coupe

Cool Thanks 4 speed!

I will giv that a try.

Does anyone have an exploded view of the control unit?


Greg

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http://www.youtube.com/hyperpack

Since I often find myself on the highway, I got to thinking that cruise control would be a nice addition to my Barracuda (once I get the wheels back on).

Recently, I had to replace the cruise control on my 03 Impala and noticed that it is quite self-contained. The controller gets its speed signal electronically instead of from the speedometer cable. I thought it wouldn't be too hard to add a signal generator to the speedometer gear - I'm sure SSDan has some PNs that would work.

Something else to consider if the OEM cruise control isn't practical to repair.

Same Cruise Control servo from 1970 and up. 1969 is a one year only unit.

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50 chrysler,54 Plymouth, 64 Valiant conv 4 speed, 66 Valiant V8 wagon, 70 Challenger R/T 440+6 conv 4 speed,80 Colt, 98 Neon ACR,84 Honda V45 Magna
Taking care of 57 300C conv,48 T&C conv. Missing my 67 GTX and 36 Ply coupe

So have you opened up the servo? Did you find anything? Update please

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50 chrysler,54 Plymouth, 64 Valiant conv 4 speed, 66 Valiant V8 wagon, 70 Challenger R/T 440+6 conv 4 speed,80 Colt, 98 Neon ACR,84 Honda V45 Magna
Taking care of 57 300C conv,48 T&C conv. Missing my 67 GTX and 36 Ply coupe

Not yet, Other Projects a bit more Urgent now;

This problem is jsut more of a nuisance, I will post updates when I dig into this one.

thanks,

Greg

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http://www.youtube.com/hyperpack

How far up?
Is a 1987 unit form, fit, and function replacement for a 1970 unit?



Robert

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Robert Troy
69 slant 6 OD4 Barracuda conv
68 383-S 4 speed convertible