Cruise Control Actuator Issue

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Griphish
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Joined: Sat Nov 21, 2020 3:56 am
Location: Charlotte NC

Cruise Control Actuator Issue

Post by Griphish »

Hello Gents,

I have an '88 M6 that I've been working on restoring for the last year. I'm in the middle of overhauling the brakes and while I have everything out I decided to change both throttle cables. When I took out the cruise control actuator I thought I had to open the cover to change the cable.

Man was that a stupid decision...

As I'm sure most of you guys know the result was not pretty. Everything unwound and I'm not sure how to put it all back together. I'm really kicking myself because I usually research everything that needs to be done on this car so something like this doesn't happen but today I was not thinking.

Has anyone had any success in rebuilding these actuators after opening them up or is my best bet to buy a new one or a used unit?

Thanks in advanced. I have been lurking on the site for over a year now and y'all have been an ENORMOUS help with this project so far!
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hornhospital
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Re: Cruise Control Actuator Issue

Post by hornhospital »

Griphish wrote: Sun Nov 21, 2021 10:47 pm Hello Gents,

I have an '88 M6 that I've been working on restoring for the last year. I'm in the middle of overhauling the brakes and while I have everything out I decided to change both throttle cables. When I took out the cruise control actuator I thought I had to open the cover to change the cable.

Man was that a stupid decision...

As I'm sure most of you guys know the result was not pretty. Everything unwound and I'm not sure how to put it all back together. I'm really kicking myself because I usually research everything that needs to be done on this car so something like this doesn't happen but today I was not thinking.

Has anyone had any success in rebuilding these actuators after opening them up or is my best bet to buy a new one or a used one?
I've successfully opened up and reassembled ONE (1) cruise control actuator. I swore I'd never do that again. Be aware with patience you can put it back together. It just takes time and some considerable forethought in how to keep it wound up while you put the cover back on. I know that's more of a "you can do it" than actual help. Sorry I can't be more specific. By the way, my actuator didn't actually need to be disassembled. It was the cruise control computer that was bad. Wish I'd thought of swapping that out before unnecessarily disassembling the actuator.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
Griphish
Posts: 15
Joined: Sat Nov 21, 2020 3:56 am
Location: Charlotte NC

Re: Cruise Control Actuator Issue

Post by Griphish »

Hey at this point any moral support is appreciated!

Is there a drawing somewhere showing how the pieces fit together and how many turns the spring needs for pre tension?

Thanks!
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hornhospital
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Re: Cruise Control Actuator Issue

Post by hornhospital »

If I recall, the tension had to be enough to pull the entire cable back into the housing. I'm sorry, it was years ago when I had mine apart.

It would be well worth spending some time figuring it out, because a used replacement is really pricy, and the shipping on this one is ridiculously expensive.

https://www.ebay.com/itm/BMW-E24-635CSi ... 632-2357-0

I'm looking for a how-to for repairing one. There used to be
a BMW rebuild kit, which is now NLA, of course.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
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hornhospital
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Re: Cruise Control Actuator Issue

Post by hornhospital »

I found what might be a schematic or exploded view of an actuator, but it's on Google drive. I've asked for access, which may or may not be forthcoming.

viewtopic.php?f=11&t=23155&p=163864&hil ... or#p163864

Scroll down until you see "cruise control actuator". It is apparently a valid link, but you have to ask for access. ](*,)

I tried downloading the links rather than attempting to open them. I get "forbidden" back. :roll: :evil: #-o
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
Griphish
Posts: 15
Joined: Sat Nov 21, 2020 3:56 am
Location: Charlotte NC

Re: Cruise Control Actuator Issue

Post by Griphish »

I've requested access also but so far no luck. :-?

I did find this post from Bimmer Forums. It's for an E39 but the unit looks very similar.

https://www.bimmerforums.com/forum/show ... ator-FIXED!

I think I'm going to give it a try this weekend and hope for the best. Thanks Again for all the help!
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hornhospital
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Re: Cruise Control Actuator Issue

Post by hornhospital »

That's an EXCELLENT write-up! Thanks for finding it and sharing the link! It brings back some of the panic I felt, too!
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
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