speedometer cable drives me nuts

[Eddyvdw]

Hi there,

Speedometer ok.
Cable checked and ok.
Drive pin from gearbox rotates when turning the wheel (in gear) even when hold by hand.

Still the speedometer doesn't work.
It worked for a bit jumping up and down but then stopped.

Can it be that the little pin rotates inside the cable connection? It seems to be a bit small for the cable housing but have nothing to compare.

Who can help me solving this very annoying problem.

I have a 72 911E with 915 gearbox.

Happy easter!
Ed

[fintstone]

Sounds like the cable. How did you check the cable? Disconect it from the back of the speedo and drive around observing it spinning?

Have a Happy Easter!

[Hugh R]

On British cars, when the speedo bounces, it's the cable in need of lube. Take the cable out and stuff graphite in it, you maybe able to pull the cable out to lube. Graphite you get in a little tube at the lock store,

[Eddyvdw]

Thanks, checked that as well. Cable rotates freely.
What I noticed is a little scuff mark on the inside of the cable part connected to the gearbox. Must be that the little pin rotates freely inside the cable connection.
Big question, how to solve this?
Ed

[fintstone]

Early cars have a speedometer angle drive Pelican Parts - Product Information: 911-318-029-00-M100
that is a common failure point for the speedo. I think they were only used prior to 72 though.

[Eddyvdw]

Well, at least I know now what caused the problem....
The little pin on the gearbox measures 5mm x 3mm.
When in 5th gear and rotating one wheel, the pin rotates and is strong.
Looks all okay, doesn't it?

Ed

[john walker's workshop]

be sure the speedo itself is not binding enough to have broken the cable.

[fintstone]

Originally Posted by Eddyvdw

Well, at least I know now what caused the problem....

Ed

LOL. Exactly what I expected. That is why I disconnect mine from the back of the speedo and drive around observing the cable end spinning. Dynamic testing at speed precludes the broken cable wires meshing at slow speed to rotate the cable ends and fooling you. Good work.

I use an electric drill and clamp the broken cable in like a bit to test the speedo to ensure it is not binding and caused the problem. ..but the broken cable is likely due to age and lack of lubrication.

[Eddyvdw]

Any suggestions where to buy a new one with the original gearbox end (long housing). Our host is out of stock.....
Ed

[ecostellodo]

I bought my speedometer cable from North Hollywood Speedometer. Perfect fit. Pain to put in.

[ecostellodo]

Agree with JWW. Check the function of the speedometer. My speedometer froze and sheared the cable in half.

I did the cable in the drill trick to check the function of the speedometer. So I also had North Hollywood rebuild the speedometer.

eric

[RWebb]

try ********'s

Good Luck

makes you want to convert to an electronic one...