Innacurate and wobbling speedometer
Thread Starter
5th Gear
Joined: Sep 2018
Posts: 5
Likes: 0
From: Bradenton
Innacurate and wobbling speedometer
I recently purchased a 1970 454 with only 2 things that I wanted to initially fix. The 1st was a frozen odometer. Speedometer worked fine with some minor wobbling up around 80-90 mph. I took apart the interior, got the speedometer unit out, and replaced the internal gear that was the frozen odometer culprit. NOT a fun project, but then again, a day working on a Vette IS fun! So put everything back together and the odometer works fine, but now the speedometer is completely crazy. Wobbles +/- 5 MPH and runs 15-20 MPH faster than I’m actually going. So have I messed up the speedometer unit, or ruined the speedometer cable. I reattached the cable and moved it around near the exit into the engine compartment with no luck. I plan to buy a cable to see if this is the culprit, but thought I’d get some input from the experts first. By the way, the 2nd thing to fix is the alarm 
Drifting
Joined: Jul 2015
Posts: 1,765
Likes: 254
From: Catlett VA
Chiton- I would suggest you go with your plan to replace the cable. I replaced all of the gauges on my 68 convert, but re-used the old cables for the speedometer and tachometer. I regret not replacing them, since the speedo needle fluctuates like a windshield wiper until it finally settles out at about 50 mph and the tach is slow to respond and is always behind the actual engine speed. You know what a PIA it is to work behind the dash, so I have been putting up with it. If you can deal with the troublesome job of working behind the dash replacing the cable will probably solve your problem.
Melting Slicks
Joined: May 2012
Posts: 2,192
Likes: 343
From: Allenton Wisconsin
I'm going to follow along, my 69 has the bouncing speedo needle and the odometer has quite working, This winter I plan on removing the speedo and have it repaired but don't know of any reputable source for the repair. So maybe some informed CF member can advise. T
