1966 Chevrolet Corvette: Broken Speedo
June 8, 2015
To be clear, that's a broken speedo. Not a broken Speedo. Shortly after being repaired, the speedometer in our 1966 Chevrolet Corvette broke again. Well, it isn't really fair to use the word repaired. It's more like we used a Band-Aid and then it fell off.
We tried a shortcut when it came to fixing the inoperable speedometer and odometer. Option A was to remove the dash, rebuild or replace the parts in question, and spend $1,000 and three to five days out of service.
Option B was to add a shim to the speedometer cable to keep it in place. A five-mile road test gave us the impression that this choice might just work, so we rolled the dice. About 15 miles later, the shim escaped to freedom.
I was accelerating from a stop light and glanced down at the speedometer. It crept at a steady rate of 10, 20, 30 mph. Right at about 45 mph, the gauge jumped to 65 mph and before I knew it, I was moving with the flow of traffic around me at 110 mph. Clearly something was wrong.
At the next red light, I was idling at 60 mph. A block later, the Corvette was idling at 110 mph. Soon thereafter the dash buzzed loudly and the needle skipped erratically. When its swan song finished, the needle went completely limp. It's rested on 0 mph ever since.
Good thing there are plenty of GPS-based speedometer apps out there. I found one with a bright, easy-to-read display. It drains a phone battery fairly quick, but should serve as a fine guide until we decide whether or not to fix the problem.
Mike Schmidt, Vehicle Testing Manager