Odometer yes, Speedometer no

TudooR31

TudooR31

Member
1931 round speedometer... has worked well last 2 years.
Now randomly stays at zero while driving but odometer continues to register miles. Sometimes speedo will jump to 5 mph by tapping on the glass. Sometimes speedometer will work normally for several miles after making a left turn.
Have cleaned & put graphite on the cable.
both cable ends looked square, not worn rounded.
Have not found this situation under search.
Can the gearing shaft inside the speedometer housing somehow move so it engages the odometer and not the speedometer?
If the cable had play and slipped back, would it not disengage both odometer and speedometer?

Hope someone else has an idea.

Thanks.
 
If the odo is still working, then it is not the cable. The odo is driven from the cable, where as the speedo is driven by a spinning magnet and drum against spring pressure. It sounds like the connection to the magnet is faulty. You'll have to remove the speedo and investigate further.
 
I recommend removing it and sending it to one of the VERY qualified rebuilders listed in the stickies above, unless you have the tools and experience to mess with these. Prices for professional help are reasonable and the results are great! Call one of them first, describe your trouble, and proceed accordingly.
 
It is possible that the magnet has come loose from the shaft and is no longer turning. Another possibility is that something is preventing the speedcup from moving freely. The easiest way to tell is to open it up and find out, and you need to get inside to fix it anyway. If you need some assistance, contact me.

mark@marksspeedometer.com
marksspeedometer.com
 
I didnt realize the round speedometer had a odometer. Mine doesnt, but it is a 1930 so they must have changed them in 1931? I know the oval have odometers.
 
Tom F: Do you mean the trip odometer? All model a's have an odometer, only the oval faced ones have a trip odometer. The exception is the oval Northeast that was made without a trip odometer.
 
Mark in MT said:
Tom F: Do you mean the trip odometer? All model a's have an odometer, only the oval faced ones have a trip odometer. The exception is the oval Northeast that was made without a trip odometer.
Click to expand...

Thanks Mark for clearing that up for me. I was thinking of the trip odometer. Here I thought I was missing something on mine.
 
TudooR31 said:
1931 round speedometer... has worked well last 2 years.
Now randomly stays at zero while driving but odometer continues to register miles. Sometimes speedo will jump to 5 mph by tapping on the glass. Sometimes speedometer will work normally for several miles after making a left turn.
Have cleaned & put graphite on the cable.
both cable ends looked square, not worn rounded.
Have not found this situation under search.
Can the gearing shaft inside the speedometer housing somehow move so it engages the odometer and not the speedometer?
If the cable had play and slipped back, would it not disengage both odometer and speedometer?

Hope someone else has an idea.

Thanks.
Click to expand...

I had the same problem with my 1930 round speedo except the speedometer worked and the odometer did not. I took it apart and learned a lot, like I should have never taken it apart:mad: I do have all the parts but man are there a lot of them.

dusty
 
I might be wrong on this, but I think you should only reset the trip odometer while the car is stopped. Also make sure the knob gets pushed all the way back in.
 
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