Speedometer Inop

[wartmeister]

Total rebuild '69 F100, Inline 6 240, 3 on the tree.
I realize this isn't elecrical, but couldn't find a better category.
Brrand new speedometer gauge and cable with new gear at the transmission end where the cable mounts.
I get nothing on the gauge at all speeds.
Removed and remounted the cable at both ends and still nothing.
Any help/comments on troubleshooting this?
Thanks.

[sargentrs]

Disconnect your cable at the gauge and make sure it's spinning with your wheels. Then take it loose from the transmission and spin it with a drill to see if your cable is spinning and it's moving your gauge. While it's out, look inside your transmission where the cable goes and check the gear in the transmission. If it looks ok, stick something in the hole to get an idea how deep it is to the gear and check that depth against your cable. Not too unusual to get the wrong gear even when you ordered the right one.

[The Bandit]

What is the brand of the speedometer? If memory serves me correctly some of the after market speedos needed an adapter for the ford cable driven style.

[wartmeister]

Thanks to both responses. I will do this troubleshooting this weekend.
The speedometer gauge and cable were from LMC.

[wartmeister]

Did the troubleshoot...turned the cable with a drill on the transmission end. Got some response on the gauge, but stuck at 15mph even after stoppintg the drill. I then disconnected the cable from the gauge and drove the truck...zero rotation / no movement in the cable. I am at theend of a 3 year rehab...this is the sole remaining issue...never would have guessed it would be this.

[sargentrs]

While you had it out of the transmission did you check the condition of the mating gear in the tranny? Check the depth to make sure it's contacting?

[sparky72]

On mine, the cable had popped out of the driven gear. Had to fiddle with it to get the cable back into the little square hole on the gear, but once it was back on the whole shebang worked nicely.

[wartmeister]

Stuck my finger and the gear was in good shape...also at a good depth. I also had a look when I had the transmission out and it all looked fine.

I think sparky72 has the answer as the cable pulled out of the sleeve at the speedometer end when I disconected it there. I'll see if I can find the little "square hole" at the gear end that you mention.

[MadMike]

If memory serves me correctly there are two different cable lengths. One is for MT the other is for AT. I think the difference is in housing attachment one is bolted on and the other is screwed on.

If you have the longer housing with the shorter cable it may look like things may work, but when in situ the cable slides down the housing and does not engage the speed-O-meter. Or if it has the nub to prevent it from sliding down the housing, it may not be reaching the trans gear.
I've used ATP brand cables in the past with no problems.

[wartmeister]

Update:
1. The speedometer needle was slightly bent and it was catching on the back of the gauge. I bent the needle and it stopped sticking.
2. Per sparky72, I made sure the cable end was seated in the square end of the drive gear at the transmission end...did a test with a drill and it worked fine.
3. Did a road test and speedometer is still inop.
3. When I stuck my finger inside the speedometer hole in the transmission, I noted the gear inside the transmission that turns the speedometer drive gear does not seem to be aligned with the hole...it seems to sit a bit to the right/rear of hole center. So the drive gear may not be seating properly with the gear inside the transmission. Can't figure out how it could have moved. Anybody familiar with the internal workings of this 3 spd manual?

[wartmeister]

Madmike...

I have the cable with a nub and the cable is not disengaging from the speedometer when I do the test with a drill.

I can't see how the cable could disengage from the drive gear since it is clipped in place? It would be nice if that were the problem.