Speedometer problems

[anotherblack944]

I've got a problem with my 84 speedometer. No it's not the usual odometer thing. Both the trip- meter and odometer advance as they are supposed to. My problem is that about every 20 feet I hear a click like a gear is slipping in the speedo, the needle will jump up like 50mph and back to actual speed. Was thinking of opening it up, thought naa, maybe I'd just get another and saw this..

http://cgi.ebay.com/ebaymotors/ws/ebayISAPI.dll?ViewItem&item=1849353036&r=0&t=0

The guy says it's off a 86!?! That's not possible is it?

[Lawrence Coppari]

My '86 has white numbers and two ticks below 20. I think the one on Ebay is not from the factory. Number format is different too. Mine looks like all the others I see.

[SoCal Driver]

The speedo cable is probably binding in it's sheath/tube.

You can try to lube it with a teflon based spray by pulling it off of the speedo and squirting down the tube. Jack the left front tire off of the ground and have someone spin it while you use the spray.

I think you can pull the cable out of the sheath if you what to check it for broken filaments. If it's bad then I would recommend that you replace both the cable and sheath. You could just replace the cable.

If you have a compressor you might want to help the spray down the sheath with a blast or two of plus 100 psi air.

Also the speedo cable terminates at the back of the speedometer at a bracket that is held on with a couple of screws. These may have come loose. Not very likely though but a remote possibility.

I don't think it's the speedo.

[emilysgranny]

First of all I believe that is NOT an 86 speedo and for sure it is not from a turbo.It is the early model 944 style. The 87-88 924s has white #'S.
Now to your problem , chances are the clip down on the drivers side spindle has comes off.Tap the wheel bearing cap off and take a look at the speedo cable to see if the little clip is still on.These speedometers are mechanically driven up to 85.5. The other thing that could go bad is that the cable is binding in the surrounding sheath from years of wear and must be replaced. They are driven by the cable off the drivers side front hub.
After 85.5 the 944 is eletronical from the transmission.
HTH.

[John_AZ]

I think your first roller gear from the cable is worn. I would like to know where to purchase the gear. This is not the odometer (red) gear available on another post. If you open the unit up you will see the teeth worn down in the center. A temporary fix is to place a thin shim between the gear shaft and case to slightly press the gear closer to the speedometer cable end drive. Lube the cable while its apart. I used a fishing reel oil and needle tube to carefully oil contact points (Wal-Mart) and silicone grease-not white grease to coat the plastic gears.

John_AZ

[anotherblack944]

Originally posted by John_AZ
I think your first roller gear from the cable is worn. I would like to know where to purchase the gear. This is not the odometer (red) gear available on another post. If you open the unit up you will see the teeth worn down in the center. A temporary fix is to place a thin shim between the gear shaft and case to slightly press the gear closer to the speedometer cable end drive. Lube the cable while its apart. I used a fishing reel oil and needle tube to carefully oil contact points (Wal-Mart) and silicone grease-not white grease to coat the plastic gears.

That makes more sense to me because of the clicking sounds like a gear slipping. I originally ruled out the cable because of the fact that it happens once for several rotations of the wheel. I think I will pull the speedo this weekend and bench test it with a drill to see for sure. Will post either way when I find out.