Cruise control actuator
 

Anyone have a pic or discription of the return spring on the half moon gear? This is the electric unit, obviously. Mine is together and working, but it fell out and I did not get a good look at where it came from.

And the reason I had this apart..

Is there a good reason the motor cover on the actuator is attached in such a way as the screws do not allow it's removal?
There is a little nub that is pressed to mushroom it out a little and act as a rivit to keep it on. I'm assuming this means there is no way to insert the armature back in with the brushes in the corret spot, and this is Mercedes way of telling me so?

I'd really like to look at and clean up that motor internaly.

Cleaning the contacts inside the actuator and re-greasing the gears smoothed out it's operation for reference. I'd hoped to clean up that motor and maybe source brushes for it and drop it's amp draw further into spec.

Thanks..

Wolf_Walker,

The same answer to you as I posted on an other thread concerning the CC.
Look in the members list for "Tasma". He had a thread about this and he opened up the servo motor for repair. So if there is someone able to help you
it's certainly him.
Good luck,

Danny

Thanks, will do. I searched a good but, but you can still miss things somehow.

:)

All right I know this is an old post but I was searching for some info on doing this on the 83 SD cruise control actuator. Has anyone had any success with opening one up and cleaning up the contacts etc? Can you explain how the process went after you had it off the car? Mine sort of works but was wondering about the cleaning. Thanks.

Anyone?

OUCH!!! come on here!!!! OK! OK! I'll be the gennypig and tear one apart for you guys!!

I just replaced mine at the same time I replaced the amp. I sent the old one back to GDL with the old amp so they can play with it.

how does that work.. I noticed they have a core price and then the price to repair one..


how much did it cost to get the amp fixed? mine has been sitting on my desk for two years now

For the amp, they do an exchange for about $215, if you don't send them the core (or if it's trashed) they charge another $115. The also rebuild the actuators if you send them in (not sure of the cost), I just bought a new actuator (about $330, I think) because I didn't want to mess with it:

http://www.gdl-online.com/price1.html

I pulled one apart to see what I could see.There is a set of brushes that could be replaced, a gear that should be replaced, some solder joints that would probably benefit from being reheated. Also there are some rivets that hold everthing together that will need to be replaced, some sort of soft metal that snapped pretty easy. There really isn't much to these, if you can get your hands on some of the rivets and gears this could probably be a fix at home job. I think I'll try this one out just to see what it does now that I cleaned it up some what.

Sounds like a lot of work for a relatively cheap part. If you don't want to buy a new one, try a junk yard. There are probably plenty around that haven't seen much service since the amp died.

I just had two of the units apart today.

My advice would be to not mess with the motor - if it is drawing too much current, or is seized get a new one from the junkyard. The motor and solenoid can be tested easily (12v across pins 4 and 5 for the motor, vice versa to reverse - 12v across pins 6 and 7 for the solenoid)

Those traces have a resistive value, so resoldering them or cleaning them with sandpaper would be a bad idea.

Well sometimes I like to see how things work and since it was an extra no harm done. Besides I get a kick out of taking something apart, fixing it and making it work. Although that is not always the case it can still be interesting. Thanks for the discussion on these.

I took mine apart as the current draw was just slightly above spec,cleaned everything up with brake cleaner oiled the bearings for the motor the best i could without removing the armature put lubriplate on the gears and reassembled.The current draw dropped from195ma before cleaning to 150ma after which is mid range in spec.the "rivets" are actually part of the casting just squashed over on the end,i was able to cut the head off them with a sharp wood chisel and there is no reason to be concerned about putting them back as i seems their only purpose was to discourage disassembly and perhaps for alignment which they still do with the heads trimmed off. My $.02 Don

Cruise control actuator spring
 

Carefully cleaning the old grease from the carbon traces on the circuit board as well as cleaning and lubricating everything else seems to have helped on the bench. The problem is that I can't figure out how the spring goes back in either and have searched high and low for the answer. Can anyone provide an explanation or, even better, a picture or diagram of how the spring gets installed with the output shaft and gear?

For anyone who has yet to do this, make sure that when you pull the case apart you also push on the output shaft so that it doesn't pull out with the cover. This way you'll be able to see how it all goes together and not end up in my predicament.