| cornerlot | -- 12-17-2013 @ 8:11 AM |
|
Will the internal works from a 1937 - 1939 speedometer work in the speedo case of a 1935-36 speedometer? The placement of the screws and odometers look to be the same, and the sweep looks the same too. I have a '36 where the needle immediate jumps up to 40mph or more as soon as the car moves, and usually is at or near the top of the scale soon after. I pulled it apart and it looks like the rotating magnet is hitting inside of the cup that carries the needle. My observation is that the magnet's input shaft has too much endplay, perhaps the cable has forced it in and the surfaces that control endplay are worn. I can't find anything on the net about disassembly and repair of a early Ford speedo. Having a shop repair it would exceed the cost of another used one. Is there something to replace or adjust to eliminate any contact between the magnet and cup? Steve
|
|
| trjford8 | -- 12-17-2013 @ 8:28 AM |
|
The 37-39 speedo is basically the same unit as the 35-36. It should work by changing the face and putting one in the 35-36 case.
|
|
| flatheadfan | -- 12-17-2013 @ 8:56 AM |
|
It has been from my experience with speedometer repairs that I have done on '35-'36 speedos is they are not quite the same either internally and externally. There appears to be four different manufactures that were used by Ford. The basic speedo face plate layouts are generally the same on all of them but the set-back odometers are located in slightly different positions. It is this difference that can prevent swapping face plates between different manufactures and have everything fall into place. As for swapping a '37 unit into a '35-'36 the only thing that can be probably done is swap cases. I have seen several examples of this swap. Tom
|
|
| supereal | -- 12-17-2013 @ 12:17 PM |
|
That is a common problem on many older speedos. It is caused by the wear of the case where the input shaft is held. Most old units don't have an actual bushing in that place, and rely on the pot metal case to keep the shaft aligned so the magnet doesn't rub the cup. We send them to Bob's Speedometer in Michigan. Their toll free number is 1-800-592-9673. They will look at your speedo and give you a price to fix it before they start.
|
|
| cornerlot | -- 12-17-2013 @ 12:53 PM |
|
Exactly. There is a brass thrust washer on the shaft, held in place on the input shaft by a flared over peen on the input end of the shaft. I was able to carefully peen the shaft over some more and take up 90% of the freeplay. Also, I found that the speedo cable core was too long by about 3/16", forcing the cable ferrule into the speedo input promoting the thrust surface wear on that pot metal housing. I shortened the bottom end of the cable today, and will lube and reassemble the speedo. Bench fit up shows everything clearing and moving free now. Steve
|
|
| EFV-8 Club Forum : | https://www.earlyfordv8.org/forum |
| Topic: | https://www.earlyfordv8.org/forum/viewmessages.cfm?Forum=18&Topic=6823 |