Jumpy Speedometer

[ron69912t]

My 69 speedometer starts at 10 mph not zero as one would expect. When the car exceeds 10 mph the needle jumps up to 20-30 mph then settles down to the lower speed (or higher). After that it is rock steady. I replaced the speedometer takeoff at the transmission but it did not help. I plan to replace the speedometer cable next. I hope it's not the speedometer!!

Has anyone had this problem and fixed it?
Thanks,
RonD

[dimps8]

Hi Ron,

mine is very similar. at speeds below about 40 by speedo will jump from zero to about 80. At rest it's ok on zero and above 60 it's rock steady. I havn't had a chance to take it any further yet but it sounds like to me my cable is binding inside somewhere. Does anyonw know if these cables can be lubricated?????

[josh912]

I replaced the cable before and it solved the problem. However, it also can be the speedo. I had the problem a year ago on the 912 and it turned out to be the speedo. Take the speedo out and connect it to a drill. If the speedo jumps, its the speedo, if not, its probably the cable.

But officer, I was only going 10 mph when you clocked me!

[ron69912t]

FYI
Palo-Alto Speedometer Shop suggested that I replace the speedometer cable, if that does not fix the problem it is in the speedometer itself. They will repair it for approx. $135.00.

RonD

[ron69912t]

Josh:

Thanks for the idea. I already have the new speedo cable so I can attach it to the speedometer and rotate it with a drill motor to see if the speedometer jumps. That way I don't have to remove the speedometer in case it's good (fat chance)!

RonD