Speedometer Cable not turning

[k_dodd@swbell.net]

Have 31 Roadster. When I bought the car the speedometer wasn't working. Previous owner had speedo rebuilt. I took the speedometer cable out of the car, greased it, and reinstalled with speedometer. Speedo wasn't working. Checked speedo by spinning cable at transmission end and works--indicated by incremental increase in odometer. Took speedo out and drove car with cable end inside car (no speedo) and it isn't spinning. The cable is all the way "in." Any ideas?

 

[Dick M]

Sounds like you need a new speedometer drive gear. It is located where the cable goes into the torque tube. You will need to determine what differential gear ratio you have in order to buy the correct replacement gear.

 

[Bob C]

You may have a drive gear for an oval speedometer. They use a cable with a
round keyed end and the round speedometer uses a square end.

 

[k_dodd@swbell.net]

This is the original speedometer cable for the car, so I doubt that is the problem.

 

[k_dodd@swbell.net]

Sounds like you need a new speedometer drive gear. It is located where the cable goes into the torque tube. You will need to determine what differential gear ratio you have in order to buy the correct replacement gear.

Are there any video or instructions on how to accomplish this? I see a lot of information about servicing the speedometer and cable, but not about the drive mechanism for the speedometers.

 

[Bob C]

This is the original speedometer cable for the car, so I doubt that is the problem.

But the rear axle or the turtle could have been changed to an earlier one.

 

[k_dodd@swbell.net]

You may have a drive gear for an oval speedometer. They use a cable with a
round keyed end and the round speedometer uses a square end.

Contemplating using a scope to look into the transmission end to verify if it is round-keyed or square. Has anybody done this? Is there an easier way?

 

[Gary WA]

Contemplating using a scope to look into the transmission end to verify if it is round-keyed or square. Has anybody done this? Is there an easier way?

Just unscrew the two bolts on the drive gear(looks like a turtle) and look at it!What kind of ****** do you have??!!