Author Topic: Tach and speedo  (Read 400 times)


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Tach and speedo
« on: December 06, 2018, 00:06:41 »
While I have the dash apart I thought I would tackle the problem with the tach and spedo. I think I found the problem with the tach (cable disconnected). It seems to work with a drill. Will know more when I start the engine.

The end of the speedometer cable had what looked to be a piece of plastic or tubing on the end that looked almost like a friction fit. I used a small flat blade screwdriver to see if the needle would move at all. At it seemed to locked up. I used a drop of oil and kept trying the screwdriver back and forth and it finally started moving a little.

Should the end of the cable have a small square end like the transmission end?

Thanks, Pete

Mike Hughes

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Re: Tach and speedo
« Reply #1 on: December 06, 2018, 00:47:49 »
Don't mess around, send both of those instruments to someplace like Palo Alto Speedometer.  They did both of my instruments a few years back when my tach started sounding funny and they came back looking like new.  My recollection is that they guaranteed their work as long as new M-B drive cables were installed when replacing the instruments in the dash, which I did.

Both ends of speedo and tach drive cables should have the square end.
« Last Edit: December 07, 2018, 00:32:06 by Mike Hughes »
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