speedometer problem . . .

[PetesPonies]

I believe I may have a drive gear problem on my '84. Speedo had been bouncing, but worked. The other day, it crapped out. Nothing. I pulled the cable loose from the speedo head and drove the vehicle. The cable did not spin. I pulled the cable out and it is fine, driven gear is perfect and cable is intact and perfect. I had another cable and used it anyway . . still nothing. I spin the head of the speedo with my finger and the needle jumps up. Its all leading to the drive gear in the transfer case being the problem. What I am wondering is if this is a common problem with these vehicles? I know little specific info about these as this is the only one I have owned and also the only one I have ever worked on. So . . is this common? If so, replacement?

 

[PetesPonies]

so more info . . I put my finger in the TC and can feel the gear. Turning the driveshaft turns the gear. But installing the cable . . no turning. I have the cable all the way in . I know how to install a cable Strange, I can't make any sense of it. With my finger, I am putting pressure/load on the gear and it still turns. The cable spins easily . . I can make it turn with little force. But the twp things mated together . . nothing. I'm confused.

 

[trail B2]

Speedo

I've dismantled A 86 90 93 92 All of those when you take the 11mm bolt out the gear goes out with the cable and is held on with like A bigger jesus clip so it could be spinning on the cable .When this happened to me I didn't have the speedometer head plugged in all the way make sure to pull on the casing if it pops off you didn't have it on all the way.

 

[PetesPonies]

That isn't the case here. I have the gear on correctly . I've installed maybe a hundred of these things on other Fords The gear drives the cable, I have tested that. It just doesn't drive it once the cable is installed.

 

[PetesPonies]

OK, what I found is that the drive gear has slipped slightly on the clip that holds it. It is still there and you can feel and see the gear, but you can also see more of the clip than you should. So . . . what size is the nut on the yoke?? I'm going to have to remove the yoke and see what I can do. Help?

 

[PetesPonies]

OK, so I removed the 1 3/16 ( 30 mm ) nut and slid the yoke off. Then after removing the seal, you are looking at the drive gear attached to a collar. The entire piece slides out. The barb on the gear clip disappeared, so I bent the end of the clip up so the gear stays in place. The collar is a friction fit between the output shaft bearing and the yoke. That is what drives the gear. I put it all back together and the speedo is working again. If anyone else has this problem, its a fairly easy deal after you remove the nut on the yoke.