guzikf

My speedometer quit working on my 1979 Corvette with automatic transmission. I pulled the lower speedometer cable off at the transducer and pulled the cable out. The nylon end appears to be broken. Could a piece of the nylon be lodged in the transducer? If so any ideas for how to get it out? The new cable is about 3/8 of an inch longer than the old.

Thanks for your help

0Willcox Corvette

Simple solution but to answer your question and offer more insight. Something caused the plastic to break so check the transducer before installing a new cable.

How to get it out. I have spring steel wire here that's used for making heater control cables so I cut off a 6" or so section... I then took a pair of side cutters and crimped teeth in the section so that it was almost like a file. I then heat this up with a small butane torch until the end is red hot..... once it's hot insert it into the head where the plastic is broken off and allow it to cool. When cool you just pull out the broken section. I've been building speedometers for over thirty years and I've used this trick so many times to remove sections from old speedo heads and is amazing how simple it is. Now you could use something else like a small thin nail and must make jiggers on it so they will melt into the plastic, then heat it up (holding it with pliers) and insert it smoking hot... into the plastic.

Now.... back to the transducer... something bound to cause this to happen. It could be the speedo but I doubt it, 1979 cars had a plastic first worm and magnet bushing and if this was an older car I'd take a look at the speedo itself, but the 1979 cars had plastic bushings in them so there really isn't anything to bind up.... Thus the speculation that you might have a transducer issue. This brings on other questions... was the cruise working when the cable broke? Was the speedometer wiggling before the cable broke...

Willcox