Changed speedometer cable, still jumping

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Steve Agrella

Steve Agrella

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Replaced the cable being very careful not to kink it, frigging needle is still jumping not as bad seem to settle down at 30.
I greased the new cable, installation was pretty simple, any suggestions.
 
It happened to me once too.

Take it loose at the transmission end.

While turning the inner cable, push it up in the sleeve.

In my case, it had not engaged the speedometer head fully, this let it slip in & it worked perfectly after that.
 
Steve Agrella said:
Replaced the cable being very careful not to kink it, frigging needle is still jumping not as bad seem to settle down at 30.
I greased the new cable, installation was pretty simple, any suggestions.
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Did you replace just the inner cable that spins or the entire unit?

if you have the old cable, hook it to the speedo and use a drill to spin it. if it still bounces probably the speedo.

I recall if the innards of the speedo have debris in them they will drag every rotation causing the needle to bounce.
 
Told you I was going to fix this *****, never give in, never give up.... Lol.
My dog thinks I hate him now he heard me working on it ... lol
 
Last edited:
halifaxhops said:
Prob the spedo need re oiling.
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I keep saying this post after post when this come up but everybody keeps saying its the cable? Swap cable, still have a problem, its not the cable, it is that simple, service the speedometer.


Alan
 
CA--- for those of us not familiar with (service speedometer) would you clarify and explain the procedure. Thank you.
Yote
 
I haven't done it myself, last time I had it done North Hollywood Speedometer did it, There is also Redline Gauges
There is lube in the speedometer, these cars are 50 years old, it needs to be replace as it probably has solidified.


Alan
 
there is no physical connection between the needle and the shaft, its electromagnetic as the shaft spins a magnet and surrounding that magnet is an airgap and a metallic cup that IS coupled to the speedo needle. Sort of like a torque convertor with no fluid. The jumping you see that is NOT cable related (rare) is most likely the odometer drive mechanism that is sticking but that is a pretty light delicate movement that is very gear reduced. I knew of an import who's speedo needle didnt have a peg and it spun with the shaft like the 1/10 second hand of a stopwatch. It had made a physical connection between the flying magnet and the eddy current cup.
 
So is there a way to lube speedometer itself or do any other maintenance to it. If so, could someone please describe what to do and the process ?
Yote
 
the only moving part of a pure speedo minus the cable is the magnet rotor and the eddy current cup with a light hairspring that acts to keep the needle on 0. Lubrication would be limited to the cable receiver, eddy current cup bearing and the magnetic disk bearing. The odometer may benefit from a very light oil on the screw gear but as these are usually made of a very hard nylon, they would not need any normal maintenance.
 
Iron filings stuck on the magnet can cause an issue as well.
 
About 1990 I took mine to North Hollywood Speedometer, got it back, no problems after that, no idea what they did, clean and lube, what? where?

Even at that time (pre-internet my first assumption was the speedometer needed servicing)

Alan
 
While on the subject,is there anyone manufacturing speedometer cables that are anywhere near original quality? all i saw some ten year ago when i looked for one was universals and direct fit ones that looked and feel very cheap and undersized.
 
Mopar part number below, I used one on my '70 Swinger & it was perfect.

A-body speedometer cable.JPG
 
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