ClassicCar

The Chrysler corp. semi-automatic transmission is not very efficient but it is simple and reliable. The major weak spot is gradual erosion and burning of the governor contact points. HERE IS A SIMPLE CURE: Connect a diode across the wiring terminals on the transmission solenoid. Connect the positive (banded) end of the diode to the "hot" terminal and the other end of the diode to the terminal connecting the solenoid to the governor. A typical diode should be in the neigborhood of 450 volts/1 amp (available at Radio Shack). The diode "shorts" the back-voltage developed in the solenoid when the points open, thereby nearly eliminating arcing and gradual erosion of the points. The transmission will operate normally with this simple modification.