Busted Speedo & Odometer: Advice Needed
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From: Northern California
Busted Speedo & Odometer: Advice Needed
My speedometer has a busted needle and doesn't appear to be accurately tracking my speed. Even though the top of the needle is gone, you can see the back end, and it seems as though it's about 10-15mph higher than my actual speed. To complicate matters, the odometer doesn't work at all. It's stuck at 55K miles (probably 955,000
) and hasn't moved since I bought it.
What should I look at to get things back in working order? The speedo? The cable? Any guesstimates on what it would cost to have this fixed? Is replacing the speedo with a working one difficult for a newb? My car is a 1968 convertible with a stock 4-speed manual and a 350 GM crate motor. I haven't changed the tire or rim sizes since I purchased the vehicle. My car is heavily modified, and I'm open to 3rd party gauges or anything that looks good.
) and hasn't moved since I bought it.What should I look at to get things back in working order? The speedo? The cable? Any guesstimates on what it would cost to have this fixed? Is replacing the speedo with a working one difficult for a newb? My car is a 1968 convertible with a stock 4-speed manual and a 350 GM crate motor. I haven't changed the tire or rim sizes since I purchased the vehicle. My car is heavily modified, and I'm open to 3rd party gauges or anything that looks good.
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
fe1ixdakatt
The problem mentioned is common. My guess is the speedometer first worm and magnet bushing is shot! When this happens the first worm and magnet will end up with excess end play and lateral movement. This can cause the magnet to grab the speed cup and slam it. . . The end result is 1:1 contact instead of magnetic drive and the needle breaks. While the speedometer may be showing a reading, the reason it shows fast is that the left over portion of the needle is probably slipped forward from being slammed.
The fact that you say the odometer is not working indicates to me that the second worm gear and first worm are both gone. This again is the result of the first worm bushing being worn out.
The only solution to this is to remove the speedometer from the can and send it somewhere to be fixed. We can fix this for you and the cost is around 70.00 plus parts.
I have a page on this exact problem at this link: http://willcoxcorvette.com/repairand...lp.php?hID=145
Willcox Inc.
The problem mentioned is common. My guess is the speedometer first worm and magnet bushing is shot! When this happens the first worm and magnet will end up with excess end play and lateral movement. This can cause the magnet to grab the speed cup and slam it. . . The end result is 1:1 contact instead of magnetic drive and the needle breaks. While the speedometer may be showing a reading, the reason it shows fast is that the left over portion of the needle is probably slipped forward from being slammed.
The fact that you say the odometer is not working indicates to me that the second worm gear and first worm are both gone. This again is the result of the first worm bushing being worn out.
The only solution to this is to remove the speedometer from the can and send it somewhere to be fixed. We can fix this for you and the cost is around 70.00 plus parts.
I have a page on this exact problem at this link: http://willcoxcorvette.com/repairand...lp.php?hID=145
Willcox Inc.
Last edited by Willcox Corvette; Jul 8, 2009 at 03:36 PM.
