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Newbie535i
04-07-2008, 06:51 AM
I've been pretty lucky that my bimmer hasn't had a lot of issues, but most of them I've been able to handle with the insight of the members of this forum. I think I have checked all the posts regarding cruise control actuators, even downloaded the cruise control actuator technical spec pdf from another website, and checked out pingu's post on actuator repair. The issue is: I took my actuator off to clean the contacts and lube the gears, when I put it back together, it doesn't work. I am under the impression that the strap should pull out at far as possible (based on how far I was able to pull the strap to disengage the throttle cable from the clevis). But the control belt drum gear has a "lip" that acts as a stop when the retraction spring holder is in place. So when it's re-assembled, the strap can only be pulled out about 2 inches prior to retracting. How much tension is the right amount of tension for the spring? And how much slack should the strap have under no load? I have the clevis right up against the edge of the actuator, yet the pdf shows it with a little more slack.
I'm pretty sure I re-assembled it wrong, but I'm at a loss to figure out how. I'm enclosing a picture, and thanks in advance for your help.

5473

Newbie535i
04-07-2008, 01:56 PM
I tried a few variations of pre-load in the spring, so far it's been too much slack or not nearly enough. Is it possible I stretched or damaged the cruise control cable, when I pulled the actuator from it to release the clevis? I am going to try removing the cruise control cable from the throttle and reattach it to the actuator outside the engine compartment, then try re-installing the entire unit. I am going to reduce the load on the spring as you suggest and cross my fingers, thank you very much pingu

pingu
04-07-2008, 04:00 PM
Hi, it's good to see that you found my post from a while ago (a year?) useful.

I wonder if you've pre-wound the spring too much? My (somewhat) distant memory thinks the spiral spring only needed to be pre-wound about a turn and a half. But that might be wrong.

Do you mean that the clevis is right up against the actuator due to the spiral spring retracting the clevis until the clevis comes comes to a stop? This is tighter than I remember, which would seem to agree with the PDF. I do remember it being a right p*in in the arse to reassemble.

Have you tried measuring all the resistances? If they're OK, have you tried reassembling it with a bit less pre-load in the spiral spring?

Newbie535i
04-07-2008, 07:58 PM
Pingu, I replied to your post incorrectly, I apologize.

I tried a few variations of pre-load in the spring, so far it's been too much slack or not nearly enough. Is it possible I stretched or damaged the cruise control cable, when I pulled the actuator from it to release the clevis? I am going to try removing the cruise control cable from the throttle and reattach it to the actuator outside the engine compartment, then try re-installing the entire unit. I am going to reduce the load on the spring as you suggest and cross my fingers, thank you very much for your feedback Pingu

pingu
04-08-2008, 03:35 PM
I think you'll soon know more than I do about this (it was a year ago!) but the cruise control cable is like a bicycle Bowden cable and I can't see how you'd stretch it. Similarly, I thought that inside the actuator, the clevis is attached to the drum by a plastic webbing that won't stretch.

I think that once you try to engage the cruise control cable with the cruise control actuator, you'll soon find out what the appropriate amount of slack is.

Feel free to ask if you've got any more questions but I think you're about to become the cruise control main man!

t.wak
04-08-2008, 07:24 PM
I'm glad I haven't dived into this one yet :)

nk530
07-17-2008, 09:06 PM
I am having some problems with my cruise, but I haven't gotten to tearing the actuator apart yet. I'm just wondering if you figured anything out yet.
Also, I missed the whole discussion of symptoms. Mine does all kinds of crazy ****. I'll be going down the highway, and the thing will just take off! Other times, it will just keep the same pedal position for, well forever, until I interfere. Actuator? am I right?