Speedo Woes

[marlonius]

Anyone ever heard of this and/or knows how I can go about fixing it? This started only about a month ago: At highway speeds (mostly above 70), if I hit a bump in the road sometimes my speedo will go out and hover back and forth between 60 and 85 while making an annoying buzzing/hissing sound. And sometimes, if I hit another bump, it will come back to the correct speed and the buzzing/hissing would stop. It doesn't happen on regular city/street driving. Any ideas? I remember trying to take the cluster apart when I installed my indiglos last April, but I couldn't get the speedo out easily, so I left it alone. I probably messed it up, but it's funny that it didn't do it until now.

 

[sdpatt]

It may be either within the speedo head or the uper cable section. The speedo uses a magnetic (non-contact) coupling between the rotating end of the cable with its magnetic disc and the spring-loaded needle movement. If the needle is sticking at one point, the problem is usually the bearings in the needle movements bearings. alight machine oil on them loosens the sticking needle.

A wavering and noisy needle is usually from a dry or damaged cable. You will have to remove the cable end from the rear of the head to be able to slide the cable core out of the sheath. It might be easier to remove the head from the cluster to accomplish this, but if you know where to press the white plastic clip on the upper end of the cable, you can remove it without pulling the cluster. Inspect the cable for damage. If found, replace. If not, relube and reinstall.

 

[twr]

marlonius:
Anyone ever heard of this and/or knows how I can go about fixing it? This started only about a month ago: At highway speeds (mostly above 70), if I hit a bump in the road sometimes my speedo will go out and hover back and forth between 60 and 85 while making an annoying buzzing/hissing sound. And sometimes, if I hit another bump, it will come back to the correct speed and the buzzing/hissing would stop. It doesn't happen on regular city/street driving. Any ideas? I remember trying to take the cluster apart when I installed my indiglos last April, but I couldn't get the speedo out easily, so I left it alone. I probably messed it up, but it's funny that it didn't do it until now.

My 95' did the same, Unfortunatly it wasn't the cable or the bearing for the needle. For what ever reason, the magnetic assembly would make just enough contact to throw my reading off by 80mph or so. A junk yard speedo fixed that problem.