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| | | | Joined: Jan 2024 Posts: 89 'Bolter | | 'Bolter Joined: Jan 2024 Posts: 89 | Rebuilt transmission, new speedometer cable, rebuild gauge cluster,
Speedometer doesn't work. I want to spin the cable at the transmission using an electric drill. Clockwise or counter-clockwise?
The test would at least help narrow down the problem area. Thanks!
1957 3100, 235 with 4 speed floor shift
| | | | | Joined: Feb 2016 Posts: 1,987 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,987 |
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Aug 2017 Posts: 660 'Bolter | | 'Bolter Joined: Aug 2017 Posts: 660 | Yes, the "drill" should be on reverse. Counter clockwise like 78buckshot posted.
1950 Chevy 3100
| | | | | Joined: Jan 2024 Posts: 89 'Bolter | | 'Bolter Joined: Jan 2024 Posts: 89 |
1957 3100, 235 with 4 speed floor shift
| | | | | Joined: Aug 2018 Posts: 1,004 'Bolter | | 'Bolter Joined: Aug 2018 Posts: 1,004 | It won’t hurt if you go the wrong way
So just experiment
But yes from the transmission end of the cable looking into the cable you need to go ccw
Because when facing the speedometer the needle is moving clockwise so you have made one half rotation in plane looking at the needle from the tranny end of the cable
When you drive in reverse really fast the cable spins the wrong way in normal operation
You speedo handles that case just fine
The clock spring is not stressed because the needle cup is bottomed out on its stop
-a | | | | | Joined: Sep 2010 Posts: 2,307 'Bolter | | 'Bolter Joined: Sep 2010 Posts: 2,307 | Spin it with your fingers the needle will jump ,don’t need to go 80 with the drill | | | | | Joined: Aug 2018 Posts: 1,004 'Bolter | | 'Bolter Joined: Aug 2018 Posts: 1,004 | Yup that’s true
If the needle won’t jump with a spin of the fingers that’s bad sign
But still
Spinning with the drill like mad in either direction will not harm a properly functioning Speedo
It has proper full stops in both directions
You are only spinning the magnet
The needle cup can’t go lower than 0 or higher than the top speed reading
-s | | | | | Joined: Aug 2017 Posts: 660 'Bolter | | 'Bolter Joined: Aug 2017 Posts: 660 |
1950 Chevy 3100
| | | | | Joined: Jan 2013 Posts: 2,232 Moderator: Interiors, Texas Bolters, Name that Part | | Moderator: Interiors, Texas Bolters, Name that Part Joined: Jan 2013 Posts: 2,232 | 3100insantafe,
I had a similar issue. I found out that the Speedo cable wasn’t seated correctly in the back of my gauge. Once I fixed this, it works great. It might be something as simple as that.
Chris | | | | | Joined: Jan 2024 Posts: 89 'Bolter | | 'Bolter Joined: Jan 2024 Posts: 89 | The speedometer driven gear has a 'square' hole in the shaft that accepts the speedo cable. Mine is round! Therefore it will not turn the cable. I am looking for a replacement gear. If anyone knows of a source, please let me know! But the cable and speedometer itself works great with an electric drill.
George
1957 3100, 235 with 4 speed floor shift
| | | | | Joined: Jan 2024 Posts: 89 'Bolter | | 'Bolter Joined: Jan 2024 Posts: 89 | And for clarification, the transmission is a 4 on the floor, SM420 transmission
1957 3100, 235 with 4 speed floor shift
| | | | | Joined: Sep 2010 Posts: 2,307 'Bolter | | 'Bolter Joined: Sep 2010 Posts: 2,307 | What is round the cable or the transmission driven gear . | | | | | Joined: Jan 2024 Posts: 89 'Bolter | | 'Bolter Joined: Jan 2024 Posts: 89 | The interior of the shaft of the driven gear. Strange, but true
1957 3100, 235 with 4 speed floor shift
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