I'm not tremendously gifted when it comes to fixing my car, but I do what I can... an altenator here, a starter there. Pretty simple stuff.

Anyway, I drove my '81 to a show two weeks ago and it never fails, my speedometer quit on me while I was out there. For the last two years, I've noticed that familiar squeal when accelerating coming from inside the dash. It kind of sounds like a progressive crunching squealing sound when I accelerate. (Sorry for the lame description.) I figured the speedometer cable just needed a little grease, but I never got around to doing it. Well, since the speedometer quit, now that crunching sound is louder. It sounds like it's coming from inside the dash, but I'm not certain it's not coming from underneath the car. The cable going into the firewall is attached and there doesn't appear to be any damage to it and all other guages are working properly.

How do I check to see what exactly is wrong? My guess is the cable snapped somewhere in the dash behind the speedometer, but that is a very uneducated guess. Any tips to find out where the problem is and whether it is an easy fix with regular tools? Are there any common problems that I should check first?

All help and opinions are welcome and greatly appreciated.


[Modified by Leos 81, 1:52 PM 8/27/2003]


[Modified by Leos 81, 1:52 PM 8/27/2003]

 

You should be able to remove the cable from the cluster fairly easily. You may even be able to get it with out removing much. Speedo cables are cheap, and hopefully it is an easy fix.

 

Hey, Leo,
The speedo in my '81 started jumping and skipping a while back. I figured it was binding, in need of lube. But just to check it out, I did this first. I disconnected the cable from the trans (I can't believe there's a simple little knurled nut holding that thing on!) and put the cable end into my cordless drill. There's just enough slack that I could lie under the car (on jackstands, of course) and squeeze the trigger on the drill while peering up at the speedo. I could clearly see that both the speedo and the cable were just fine. At any steady speed on the drill, I got a steady indication on the speedo gauge. That meant my problem was elsewhere. A quick yank on the plastic gear carrier in the trans case to pop it loose, and I could see the problem: the plastic speedo driven gear was stripped.

You can get those from suppliers like Zip and Mid-America, but I was lucky and my local Chevy dealer had the gear and the seal, as well. They were just a few bucks. Now the speedo works like new. :cool:

 

Wow Gator! I'm not sure I would have thought of that. I think I can give that a try. My speedometer has been jumping like crazy all summer. Maybe I've been having the same problem and it just had it. I'll have to get under my car this weekend for a look.

So am I to assume that if my speedo doesn't turn when I do this, the problem is somewhere further up?

Thanks for the help! Anyone else with additional suggestions or tips?

 

Yup. What you can do to check out the top end is unhook the speedo cable from behind the speedo and spin it by hand. How? 'easy'

There's a clip holding the cable to the speedo. With the skill of a contortionist, get one hand up under the dash and find the cable. Move your hand toward the speedo, and press on that clip with your thumb (toward the speedo) while pulling the cable out with your fingers that are wrapped around the cable.

Then you can spin the 'dial' on the back of the speedo and have someone tell you if the needle is moving. You can also feel how freely the speedo is moving.

Good luck!

 

You can also check to see if the cable is in one piece by taking the cable off the back of the speedo (like stated above) then pull the cable out with a pair of needle nose if its in one piece lube it and put it back in.