Cruise Actuator inop. - PeachParts Mercedes-Benz Forum

snookwhaler · #1 03-04-2010, 09:39 AM

I have been searching for a thread on this and I cannot find it. Has anyone taken a Cruise control actuator apart?

I ran some tests that are posted over on GDL's site and it basically failed all of them. I figure if it is this bad, a "tune up" is out of the question and it will need to be completely rebuilt or replaced. Why not open it and see what I got? Would it be as obvious as a burnt armature, or magnets that have fallen off.... Or something more sinister and not as obvious?

Jeremy5848 · #2 03-04-2010, 12:19 PM

Doesn't Diesel Giant have a DIY on his web site to overhaul the actuator?

snookwhaler · #3 03-04-2010, 12:27 PM

Quote:

Originally Posted by Jeremy5848

Doesn't Diesel Giant have a DIY on his web site to overhaul the actuator?

Thanks... I looked over there and did not see one.

I took it apart and found the motor seal was pinched. At some point water got in there because of the pinched seal and rusted the armature to the magnets. It had never been apart before, so this is a factory/assembly line screw up.

The circuit board, potentiometer and all the traces look good. But I'm worried about the solenoid. It looks pretty rough.

I got it all cleaned up, regreased, etc... Everything tested good when I had it apart. The gears are fine, etc... I'm going to run the GDL tests again when I get it put back together. Here in about 15 min.

snookwhaler · #4 03-04-2010, 01:52 PM

Ok... This thing works. The motor and the solenoid both work.

Only problem is that the rust beneath the magnets has pushed them too close to the armature. I'm soaking the housing in some solvent so I can remove the magnets, clean the rust out of the housing and re-attach the magnets. I'll run GDL's tests after I get the magnets glued back in there.

I'm pretty sure that after some reading that this particular actuator probably fried the amp inside the car.

snookwhaler · #5 03-04-2010, 04:06 PM

Here are some pics of the cruise actuator taken apart (for those that are interested). This actuator was seized up and the motor was not turning. Upon removing the actuator from the car and opening it up, I found rust was the reason for the actuator not operating.

The actuator is currently partially assembled. I had to remove the magnets from the motor housing because the rust had pushed them out too far and they were contacting the rotor.

My goal is to get the motor within the specs listed over at GDL's website. 120 to 180 mADC with the motor running.

Pics below:

Bracket removed from car
http://i247.photobucket.com/albums/gg133/litespeed58/actuatorinbracket.jpg

Actuator removed from bracket
http://i247.photobucket.com/albums/gg133/litespeed58/removedfrombracket.jpg

Arm removed
http://i247.photobucket.com/albums/gg133/litespeed58/armremoved.jpg

Cover screws removed
http://i247.photobucket.com/albums/gg133/litespeed58/coverscrewsremoved.jpg

Cover removed
http://i247.photobucket.com/albums/gg133/litespeed58/coverremoved.jpg

Big gear removed
http://i247.photobucket.com/albums/gg133/litespeed58/biggearremoved.jpg

Crescent gear removed and potentiometer traces
http://i247.photobucket.com/albums/gg133/litespeed58/crescentgearremoved.jpg

Potentiometer brushes
http://i247.photobucket.com/albums/gg133/litespeed58/Potentiometertraces.jpg

Rusted rotor and pinched seal
http://i247.photobucket.com/albums/gg133/litespeed58/rustandpinchedseal.jpg

Pinched seal
http://i247.photobucket.com/albums/gg133/litespeed58/pinchedseal.jpg

Rusted housing
http://i247.photobucket.com/albums/gg133/litespeed58/rustedhousing.jpg

Edit: More below

Cleaned rotor/armature, greased bearings, gears, etc.. and re-assembled
http://i247.photobucket.com/albums/gg133/litespeed58/Rotorcleaned.jpg

Cleaned housing and gluing the magnets back in
http://i247.photobucket.com/albums/gg133/litespeed58/Gluingmagnets.jpg

andrewjtx · #6 03-04-2010, 04:29 PM

Quote:

Originally Posted by snookwhaler

I took it apart and found the motor seal was pinched. At some point water got in there because of the pinched seal and rusted the armature to the magnets. It had never been apart before, so this is a factory/assembly line screw up.

Take it into an MB dealer, see if you can get it warrantied...

compress ignite · #7 03-04-2010, 05:12 PM

SN,
Thanks!

HammerWerfer · #8 11-25-2010, 04:17 PM

AJ,

I am working on my spare Acctuator before I go digging into my working on that is on the car. When I got down to the traces on the circuit board, I found the traced covered in a black grease like material. Looking at your pictures, it appears that your trace was also covered. would this be di-electric grease, or contamination from the gears?

Also, Did you figure out what grease was used on the gears? Looks to me to be chassis grease.

Thanks for the guidance

Hammerwerfer

snookwhaler · #9 11-25-2010, 06:56 PM

Quote:

Originally Posted by HammerWerfer

AJ,

I am working on my spare Acctuator before I go digging into my working on that is on the car. When I got down to the traces on the circuit board, I found the traced covered in a black grease like material. Looking at your pictures, it appears that your trace was also covered. would this be di-electric grease, or contamination from the gears?

Also, Did you figure out what grease was used on the gears? Looks to me to be chassis grease.

Thanks for the guidance

Hammerwerfer

I think that the black stuff you are seeing is residue in the grease from the brushes. There are small brushes attached to a spring that ride across those traces. The grease might have been clear at one time? But with those black brushes running across them over time.... What ever it was, turned very black.

Have you pulled the amp or run any of the tests on GDL's website? I would start there. If your actuator can pull at or less than the rated amperage in their test, I would just clean and grease the parts on the "gear side". Use a good synthetic like Super Lube. If it is drawing more than advertised you can play with the motor side. It is a fairly simple device. Once you have it apart, you will see.

My main problem with this particular actuator was water damage from a factory defect (water intrusion due to a pinched seal). This in turn eventually damaged the cruise amp.

Mine finally gave up the ghost a few months ago and instead of forking out all the $$$ to replace both components I just replaced the whole system with a Rostra Electronic unit and wired it into the factory stalk. It works VERY good!

If all else fails and if you are interested... Rostra Thread:

Rostra Global Cruise Install Thread