Hello folks. I have an unusual issue with my 1969 speedometer, and hope you can help. I have not worked on the speedo head, but have replaced the cable. The speedometer does not work when first cranked and run. It used to start working about 2-3 miles out during the drive. The distance has slowly increased to the point that I have to drive 8-10 miles before it starts working. Once it's working, it stays working and doesn't bounce. I can stop somewhere, cut it off and come back to the car in 10-15 minutes, and it works immediately at start. But if I wait more than an hour or so, it reverts back to not working at srart. Any idea what might be happening? When I replaced the cable this weekend, I was certain to get the cable engaged in the transmission properly. I thought the cable might be too short or not installed properly, and was only engaging after it heated up and lengthened. But the same symptoms are happening with a new cable. Thanks in advance for any help you can offer.

Keith

My guess would be the mating gear inside the Trans but I have know idea why it would take a distance before it started working. That is odd.

Thanks, Robert. Any other thoughts, anyone? I appreciate your help on this puzzler.

Keith

Just a guess, but it must then be a coincidence that it started after changing the cable. Maybe the speedometer needle is binding when the car is cold? If so, the odometer should still work, even if the speedometer doesn't register anything.

Thanks, Ronnie. When the speedo isn't working, the odometer is not working either. This would lead me to believe it is physically disconnected at one end of the cable or the other when not working. But I've had the same symptoms with two cables.

Keith

Either the speedo drive or driven gear inside the tranny is worn and partially stripped. Both are plastic. When it's cold, the distance between the two prevents mating. When they warm up and expand - they mesh.

I'm going to surmise your problem is inside the train as well.
You said the speedo needle and odometer both do not work together, which leads me to believe the cable is not turning. Inside the speedo head, the needle is a magnetic drive while the odometer is a gear driven system right from the cable. Even if the needle was stuck the odometer should work if the cable was turning.
You could test that by hooking the end of the cable (after pulling it from the trani connector) and chucking it in a drill and see if it works then.

Thanks, gentlemen. I will try the drill test this weekend, and let you know the outcome.

Keith