Speedometer Question ???

[VANDAN]

So my '63 is back together, and roadtesting in progress. My speedo is not indicating my speed, but the odometer is recording the mileage ? Funny thing is, my friends '65 is doing the same thing. Do any Pro Mid 60's veterans, have some input, and a solution ? Thanks for any, and All input !!!

 

[493 Mike]

The needle is magnetically driven so a bind, dry bearing, or some obstruction could be present, or it could just be worn out. It is over 60 years old. Many days I feel worn out.
Mike

 

[VANDAN]

Thanks Mike. It worked fine when disassembled, but sat for 7 years. It just seems strange that both cars are acting the same ? Can you elaborate a bit more on the magnetically driven ? As I said, both odometers work ?

 

[pnora]

Thanks Mike. It worked fine when disassembled, but sat for 7 years. It just seems strange that both cars are acting the same ? Can you elaborate a bit more on the magnetically driven ? As I said, both odometers work ?

How do speedometers work?

 

[493 Mike]

Thanks Mike. It worked fine when disassembled, but sat for 7 years. It just seems strange that both cars are acting the same ? Can you elaborate a bit more on the magnetically driven ? As I said, both odometers work ?

That is why I suggested the speedo needle issues, we know the cable is driving the speedo gears. The needle is attached to a thin steel cup around which a magnetized strip rotates. the drag of the magnet causes the cup to turn and more speed causes the cup to turn further, indicating a higher speedo reading.
Mike

 

[wagonman]

I have also found NOT to lube Excessively It will contaminate the strip and take forever to dissipate. Even a light oil like WD 40. A little goes a long way. Mike I laugh at your self description every time you post some thing. Sorry to say I am in a close second place and sliding towards Home plate. feel your pain. I aint broke but am fairly bent.

 

[Ray70Chrg]

That is why I suggested the speedo needle issues, we know the cable is driving the speedo gears. The needle is attached to a thin steel cup around which a magnetized strip rotates. the drag of the magnet causes the cup to turn and more speed causes the cup to turn further, indicating a higher speedo reading.
Mike

Hi Mike, My speedometer reads about 14-15% faster than what my GPS phone app. The rear tires are 27"and speedometer gear in the trans is the proper one for tire size and diff. ratio. The milage driven matches the GPS app. From what I gather, I'm thinking that the rotating magnet has lost some of its strength and allowing the steel cup to rotate further. Thanks for explaining how it works.

 

[VANDAN]

I have also found NOT to lube Excessively It will contaminate the strip and take forever to dissipate. Even a light oil like WD 40. A little goes a long way. Mike I laugh at your self description every time you post some thing. Sorry to say I am in a close second place and sliding towards Home plate. feel your pain. I aint broke but am fairly bent.

The lube may be part of it ? When I cleaned the cable up, I did use quite a bit of lube on it. Maybe some drivetime will start to dissipate it, and allow it to function ? Thanks for that advice wagonman...