When I asked the customer when this machine had it's last tune-up they said it never had a tune-up. I suggested a complete tune-up-- ie--- plugs,wires,cap,rotor button for a start.

I am not at all sure there is a relationship, sometimes trucks just fail, especially when they get older. [I say that the older parts get jealous of the newer parts]. is it when they put it in gear, or when they rev the motor, since the gov. works in relation to motor speed and amount of air going through the throttle throat, and not the motion of the truck. if it is related to the truck motion, I would be checking the wiring to to coil.

edward t, I just got a phone call from the customer and they said that the machine is now stalling all the time. Any suggestions on what to look for now? It starts up fine but as soon as you put it in gear it stalls

edward, I installed the Gov on the machine and adjusted and it works fine now... Thank-you for replying so quickly...

you "should". Do you 'have to'? that depends on how you define 'have to'.
I think the short answer should be "yes, to be sure it works correctly".