36 Speedometer-What am I doing wrong?

Psych

Psych

Senior Member
I checked the speedometer with a test cable and it moves correctly. The inner speedometer cable moves when the rear wheels are in motion. The cable moves in a CCW direction. I have tried stopping the inner cable with my fingers and it does not stop. When I connect the cable to the speedometer, nothing happens, not even a slight movement. Any idea would be appreciated.
 
If your speedo is moving with a drill and a test cable. And you can't stop the cable with your fingers when the car is in motion then it only stands to reason the cable is not fitting into the speedo adapter correctly or not deep enough. It could also be that your not turning the rear wheels fast enough for the speedo to register.
 
Neil, I don't recall CW or CCW, but that would be all I can think of if cable & speedo work. The "turtle" containing the driven gear bolts on with the cable connection to the drivers side. Would it turn backwards with it bolted on the other way if it fits?
 
I have had this problem on many Model A Speedometers. Nothing wrong with the speedo or drive gear assembly. Problem was/is with the repop speedo cable. The square end that fits into the speedo is too small. It is not large enough to fill the square hole in the speedo. I have fixed the problem by purchasing a universal replacement cable from NAPA and cutting it to proper length.
 
if you have the speedo end of the outer cable jacket off, you should be able to pull the inner cable out and inspect it, lube and replace it if it is OK. I would also suspect the outer jacket is not seating properly and allowing the inner cable to be fully inserted in the rear of the speedo, The inner cable should be about 1/2 inch longer than the outer jacket at the speedo end, and the round end of the outer jacket should fit over the round end of the speedo and when the thumb nut is tightened the outer jacket should fit tight without any play in the outer jacket. The thumb nut should bottom out the round end of the outer jacket removing any play.
 
Thanks for all that responded. The problem was twofold. First, the speedometer was stiff from being gummy and sitting for many years. When I checked it with a drill and small shaft, the drill had enough torque to turn it. I had replaced a broken inner cable with the cut to length one from NAPA. The crimp I made was not tight enough and would slip under the friction from the speedometer but not from the pressure of my fingers.
Probably could not everything just to duplicate this again in a hundred tries. Thanks again.
 
FWIW, here's my tech on freeing up gummy speedometers...it will improve one whose main problem is old lubricants:

Here's my speedo repair technique: remove bezel and glass, get speedo out of case. Get a tin can or something that allows you to set the speedo down with face up and secure balance, and study how you are going to hold the thing so neither your fingers nor the liquids to be used can touch the face or odometer. That stuff is VERY delicate and easy to destroy.
Near the cable end, on what amounts to the speedo's main bearing, is a tiny brass plug. Get it out--I usually manage to extract them unhurt by threading a tiny machine screw into the cup--and extract the piece of felt within.
I then repeatedly flood this lube well with first kroil then WD40 as it frees up, sometimes liquid wrench if I feel something thinner is needed. You want lots of fluid to go in there and then leak out the bottom to dissolve and wash out the petrified lubricant and crud.
When the shaft will spin freely by finger twirl--you should be able to get 5-10MPH easily by finger--soak several times with carb cleaner and then brake cleaner to remove all those miracle solvents. When drained and dry, I fillerup with Marvel Mystery Oil, based on my scientific observation that the only real speedo tech I ever saw in action used something that sure looked like MMO. Stuff felt&cap back into hole, well soaked. Let drain, reassemble.
The multiple screwdriver tip sets you can get at discount stores contain a Canadian Robertson tip (square) that fits early Ford speedos and allows you to motor them up. You can also do a very rough test based on the supposed RPM of your electric tool, based on the speedo's calibration of 1,000 RPM=60 MPH.

Here's a ratio test page:

http://www.speedometershop.com/rep-pag.htm
1. http://www.speedometershop.com/rep-pag.htm

 
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