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-   -   '63 Tempest Speedometer (https://forums.maxperformanceinc.com/forums/showthread.php?t=833228)

elefantrider 08-18-2019 02:29 PM

'63 Tempest Speedometer
 
All of a sudden is making a ton of noise, and the needle is bouncing to 100+mph speed when I go over 30MPH. Can this be lubricated or does the it need to be taken out and sent to a speedometer shop.? What causes the needle to jump so much?
I disconnected the cable under the dash, could not stand the noise.

Peter Serio 08-18-2019 03:07 PM

Wise move to disconnect the cable.

What has happened is your speedometer is completely dried out. This happens to all old cable driven magnetic speedometers. The cure is to remove the speedometer & send it to a repair shop. These speedometers are not field serviceable and at this age it's long overdue for an overhaul. Cleaning, inspection, replacement of worn parts. Re-magnetize and calibrate. This should be done around once per every 100,000 miles or 25 to 30 years whichever comes first. There are 2 oil-lite bushings inside of these speedometers. One big one and one tiny one. Over time (as well as miles) those 2 bushings dry out and the magnet shaft trying to turn inside of the bigger bushing without any lubrication is what is causing your pointer to "jump." Running one of these old speedometers dry; the magnet shaft gets all torn up by lack of lubrication, often to the point where it's ruined.

I have taken apart 6 old speedometers in the past month and; all of them the magnet shafts are ground up. The steel touch surfaces actually turn blue and purple on account of the heat (friction).

elefantrider 08-18-2019 03:59 PM

Wow Pete......Good thing is right! Thanks.

Can spraying Teflon lubricant in the cable hole help to lube the bushing, at least temporarily?
For sure, I don't want the lubricant to hit the silkscreened(?)-number face.

How hard is it to remove the speedo only from the 63 cluster?

hobbygto65 08-18-2019 07:16 PM

In my experience it's your cable that needs to be lubed and nothing wrong with speedometer head. When the cable sticks it makes the needle jump.

Peter Serio 08-19-2019 01:05 PM

Speedometer Cable Lube.
 
1 Attachment(s)
I agree, try removing the center spinning section of the cable, clean and lubricate that first.

That's a really long cable, I think it's 118" or 121" inches long.

If that doesn't cure the jumping then by process of elimination, it has to be in the speedometer.

You say it's jumping form 30 MPH to 100, that's a pretty big jump. A dry or worn cable will cause the pointer to waver and bounce, sure. +10, +20 But +70 MPH jump I can't recall ever hearing of or seeing a cable that dry.

Try the cable first and report back. DO NOT USE White lithium grease on the cable!!!!! Try this:

Sanduners 04-24-2021 10:52 PM

Same thing happened to me today. Just got on the freeway and the needle was fine then NOISE and the needle looked possessed.! :fear: Going all over the place and about a minute later it fell out. :confused13: Now it is laying on the bottom of the speedo. Oh, the noise stayed for quite some time, the odometer was still trying to work. Then the noise stopped, but will come back for a bit if I hit a bump in the road. I'm not looking forward to removing the dash... :mad:

JohnFromVentura 05-18-2021 02:49 AM

Send it to N. Hollywood Spedo.


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