You have a wheel which turns a gear and in turn flips the number to its left (as you're looking at the odometer) with each revolution. On one side of the wheel are gears which constantly turn the small gear. On the other side there is a gear which only has one operating part. This is devilish difficult to explain (unless you are looking at it) so I've included some images. The first image below shows the inner part which always turns the small gear. The second image shows the small gear and the third image shows the wheel which "clicks" over once per rotation. Either something has broken or something has slipped out of place. Unfortunately replacements parts are not available unless you buy a used speedometer. I've posted printable decal templates for renewing the odometer wheels. Let me know if you need them and I'll show you where they are stored. Hope this helps.
Last edited by Jon G; 06/27/202410:30 PM.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end