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So decided to finally tackle my non-functioning speedometer after reading the repair threads on here.

Problem was that the speedo needle would stick and wasn't moving with any consistent motion. I removed the unit from the housing and all the gears appear to be meshed correctly and none are loose. However, when I fiddle with the round brass-colored bearing-like thing on the back of the unit, it seems to slide down into the unit slightly more (towards the front of the speedo), and then turning the small drive cable, the needle appears to move correctly.

So it appears that the brass-colored bearing thing is loose. Any thoughts on how to repair it? I suppose I can disassemble the unit more since I don't have anything to lose...

Thanks.

Why not disconnect the cable from the front diff and hook a drill to the end of it and see if the speedo works or is the cable fubar'd 1st before you go tearing into things!

Already did that. The speedo cable is ok. The speedo isn't.

Is the bearing a compression fit? I cannot recall right now. Maybe get some Loctite 641?

The bearing thing (I'm not sure that's what it is) sits on a shaft, which goes into the back of the unit. The shaft seems to be loose. So by fiddling with the bearing and shaft, I can get the needle to work as it should, but it won't remain in that position without some outside force.

I've removed the back part where the cable goes into the unit, which is attached with two screws. The round disc-like piece inside the back part has a magnetic rim. So that fits inside the metal cup-like piece that's attached directly to the speedo needle.

Moving the cup-like piece, the needle moves. Letting go of the cup and the needle sometimes returns to 0 and sometimes doesn't doesn't.

Putting it back together, when turning the cable, the needle sometimes moves with the turning of the cable, and sometimes doesn't - it seems like it's slipping.

The cable is ok, the angled drive appears to be ok. Anything else to check? Maybe it's time to bite the bullet and buy an electronic VDO speedo?

Thanks.

I'll hazard a guess that perhaps the speedo input shaft is moved too far out, and isn't properly effecting the speedo needle.

Underneath the magnetic disc is a smaller metal disc with a slot which slips over a groove in the input shaft. It seems to be there to prevent the magnetic disc from bottoming (outward) in the housing. To get the input shaft out of it's housing, it's necessary to remove the long worm gear which intersects with the input shaft. (It's this worm gear which drives all the odo mech.) The worm gear is enmeshed with gears on the input shaft, so it must turn as it comes out. It's held in place by a driven-in ball-bearing. To remove the shaft, carefully drive it into the housing while allowing it to turn. The shaft pushes the ball-bearing out, and the shaft follows. Once this is out, the input shaft will come out of the housing, magnetic disc end first. If the small metal disc is loose in there, I'd try to put it onto the shaft and see if it helps. Reassembly is the opposite.

I'm not sure I understand your instructions, but I'll have a look at it again. I bought a VDO speedo to replace the old one, but I'd like to get the original one functioning again.

Thanks.