HELP: Speedo Cable Mystery

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Jcat
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Joined: Thu Aug 02, 2012 8:01 pm
Location: Roswell, GA

HELP: Speedo Cable Mystery

Post by Jcat »

I have 3 sections of cable on my 81 528i. First, there is a "Shorty" (about 310mm tip to tip) coming out of the back of the Speedo. Shorty connects to a Nr-2 cable just inside of the firewall behind the brake pedal. The other end of Nr-2 makes its connection at a welded bracket where it meets the third cable (roughly 700mm) which travels onward to the transmission. Not sure how long Nr-2 is, but I would say roughly 480mm.

Why can't I seem to even find BMW part numbers for Nr-2? Does anyone else have 3 cables like I do? I understand that there might be a 2 cable set-up that was stock on certain model years... I want to replace them all! But where to buy? Dealership only shows 2 speedo cables: an "upper" and a "lower". ARAHALAHHHHGGGGGHHH!!
J Prothero
Roswell, GA
Former FF Ambassador to Montvale
1981 528i stock
Jprothero600@gmail.com
HB528i
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Location: Huntington Beach

Re: HELP: Speedo Cable Mystery

Post by HB528i »

They only show the long cable now. There is box where cable #2 attaches, it is just a counter with a button to reset the Ox sensor reminder.
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Jcat
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Re: HELP: Speedo Cable Mystery

Post by Jcat »

Not sure I understand. So you saying that from the tranny to Shorty out the back of the Speedo is one long cable now? ...and the bracket where Nr2 and 3 join is bypassed? If so, I cannot find a part number for such a cable because they seem to be way too short.
J Prothero
Roswell, GA
Former FF Ambassador to Montvale
1981 528i stock
Jprothero600@gmail.com
HB528i
Posts: 74
Joined: Mon Dec 09, 2019 7:53 pm
Location: Huntington Beach

Re: HELP: Speedo Cable Mystery

Post by HB528i »

The only cable BMW sells is the longer of the three from trans to the mileage box. From there the second cable goes inside and attaches to the third short cable. I don’t know of any much longer single cables but there might be something out there or you will need to find used cables. All 79-81 528i have this box as it is a reminder to check the O2 sensor. Didn’t the 530i have this same box but to remind one of the Reactor Service?
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Robert Bondi
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Re: HELP: Speedo Cable Mystery

Post by Robert Bondi »

Yes, on the 530i having the same box for reactor service reset.

I bet the 3 cable setup is U.S. O2 and thermal reactors were emission equipment generally not on the Euro
cars. Just checking under my Euro 528, there is no service box. The 2 cable setup is for Euro cars.

Unfortunate that the parts availability declines every day.
Robert
77 530i
77 Euro 528
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Jcat
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Location: Roswell, GA

Re: HELP: Speedo Cable Mystery

Post by Jcat »

Indeed it is unfortunate. Mercedes crushes parts availability. Pya thru the nose, but its an option that keeps their old cars on the road as a testament to heritage and durability and popularity and eventually... value. Good thing here is that I suppose I can have one custom made by sending the old in. Mine isnt exactly broken, so its not a pressing matter. I just want to replace stuff as I get into various areas of the steady upkeep and restoration. Thats all. Thanks Robert!
J Prothero
Roswell, GA
Former FF Ambassador to Montvale
1981 528i stock
Jprothero600@gmail.com
PatinaBeforePolish
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Re: HELP: Speedo Cable Mystery

Post by PatinaBeforePolish »

Anyone tried using a universal cable and bypassing the O2 sensor box? Personally I don't need a reminder every 30k to replace and oxygen sensor.
79 528i
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Jcat
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Re: HELP: Speedo Cable Mystery

Post by Jcat »

That would definitely work. its just that my illness come from being a pure stock guy. So I want everything to work as it should when the car was built in 81. So I would have the elusive third cable made, if stock is NLA. I know this is not exactly what others would necessarily do, however.
J Prothero
Roswell, GA
Former FF Ambassador to Montvale
1981 528i stock
Jprothero600@gmail.com
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