1961 c-10. inline 6, with 3 on the tree. speedometer seems to work properly until you hit 40m/p/h then it stops. any ideas on how to troubleshoot/ fix this?
Repairing speedo To diagnose your speedo problem. Unscrew speedo cable from back of speedo, raise car up on jack, run car up to 40 mph. If cable quits turning, you have a bad speedo cable or gear. Check inner cable at transmission, if cable shows damage or rounded,also check cable where it is inserted in speedo head look for damage, if worn or damaged replace replace inner cable. If looks good check speedo gear for damage. Another way to check cable is run at 40 mph, try to stop cable from turning with your fingers, if you can stop it , gear or cable bad. If all of this looks good you have a bad speedo.
