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General Tech Speedometer Not Working

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KVH

KVH

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I disconnected the Speedo cable from the back of the speedometer and can feel that nothing is turning. The cable is not broken. Is the problem more likely the speedometer or the angle drive? I have a 4A with O/D. (Not looking forward to getting under the car again real soon—it’s been a way of life lately)
 
If the cable doesn't turn when the car moves, then it has to be the cable or the drive to it. The angle drive seems to be the most common failure (and also the most expensive).

If it is the angle drive, I recommend also checking how easily the speedo mechanism turns. I've seen them where the head just seems a bit tight when it's cold, but it heats up and binds hard if you drive for any length of time. The angle drive is the weakest link ...
 
TR3driver said:
If the cable doesn't turn when the car moves, then it has to be the cable or the drive to it. The angle drive seems to be the most common failure (and also the most expensive).

If it is the angle drive, I recommend also checking how easily the speedo mechanism turns. I've seen them where the head just seems a bit tight when it's cold, but it heats up and binds hard if you drive for any length of time. The angle drive is the weakest link ...
Click to expand...

Yeah, that's a real possibility. My Bugeye Sprite had a gear-reduction unit for the tach, and it broke a second time before I realized what was happening. The tach's mechanism was really stiff. Cleaning and relubrication fixed it. Replacing its innards with electronics fixed it even better.
 
I’m trying to remember—does the angle drive slide out easily or is it driven in tight? Or am I confusing the drive with the internal bearing for the gear?
 
Should be a collar that screws on, just like the end of a speedo cable.
 
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