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Speedometer

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wsm

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The speedometer cable broke on my '74 Midget a month or so ago. I replaced the cable and the speedometer worked fine until this week, when it stopped working again. This time it doesn't appear to be the cable, since I can hear the cable "clicking" under the dash while I'm rolling. Does anyone have experience with this problem?

Thanks,
 
Be sure the cable has "seated" into it's drive hole in the speedometer. The end of the cable is square and it is easy to not have the cable completely seated. You can fiddle with the cable and turn the seat slightly to see if the cable inserts further into the back of the speedometer then screw the end tight. Rick
 
While you're checking the connection on the back of the gauge, put a drop or two of light oil (3-in-1 or similar) on the surface around the square hole on the back of the gauge. You don't want a lot of oil wicking its way into the gauge but a little may help.

The arbor with the square hole in it also drives a worm/pinion arrangement to work the odometer. The old oil on the pinion gear and the oil around the square input shaft can stiffen over the years. If the cable is seated, that hardened grease/oil could be your problem.
 
Thanks for the replies. When I compare the square "cable" to the drive hole in the speedometer, it doesn't look like the cable extends far enough down into the drive hole, or for whatever reason I don't think it's seating properly, even though I secure the connection very tightly. Also, it doesn't seem to make any difference how I insert the cable into the drive hole, it goes the same distance in no matter how I turn it. The drive hole is clearly square, but it doesn't seem to be holding the square cable securely. Can you think of any reason why it would come unseated? I can definitely hear the cable clicking at the speedometer. Any ideas? Thanks.
 
Check that the speedometer drive arbor turns freely. You may be able to insert a small screwdriver into the square arbor and it should turn freely. If it is siezed, that is your problem. Also check that the square end of the speedo cable has not been rounded off. If the speedo turns freely and the cable end looks good, you might have a cable that is too short. Rick
 
I presume from how this post started that you have both a new cable and sheath. Is this correct? It could be that they made the core "too short".

Out of curiosity, can you use a pair of needle nose pliers to "pull" the core up when you unscrew it from the speedometer?
 
Yes, new cable and sheath from Moss. I'll try pulling the core up with pliers, but the thing was working fine after the new cable was installed, for the past several weeks, until two days ago. I've been assuming that something jogged loose when I was driving. Thanks for the idea. I'll check it.
 
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