LarMan

Out running some errands in the '73 yesterday.

I look down and Lo and Behold.... The speedometer is now working! It has never worked in the 3 weeks I've owned it. The PO said it would work from time to time. Seemed to be working properly. Smooth, not jumping, ...

Any ideas what will cause it to sometimes work and sometimes not? I was PLANNING on replacing the entire thing but perhaps the fix is a loose connection or gear away.

Thanks.

LarMan
Houston, TX

FireballXL5

Make sure the cable is properly seated in the back of the speedo.. It's got a square tube shaft that fits into the speedo and a little retaining clip... It depresses fairly easily, and removes easily... Just make sure it fully seats into the speedo and gets clipped in place...

I would suspect it is there, and not at the trans where you are having your issue... Especially because it magically started working again... It's a mechanically driven gauge ...

hugie82

I would start with a well lubed replaced cable drive. Sometimes the square cable ends get rounded and are basically stripped out. Temper changes and it gets a little grip, then it works.
The biggest problem area is that 90* turn coming out of the trans. Some have a gear drive unit, others have a metal brace holding the cable on a tight bend. This is what usually causes stress and failure.

terry82

that square tube on the ends gets rounded off then it will work off and on.replace cable.

TimAT

If you have cruise control, the transducer goes stupid sometimes too.