[77newell]

Assuming that when you turn the key to ON prior to START the gauges power up then you have at least some battery power. If when you then turn the the key to START absolutely nothing happens then there is an open somewhere in the start circuit. On my 77 coach there is a switch in the rear electrical compartment that by-passes the transmission neutral switch. There have been times when I just couldn't get the starter to engage despite jiggling the gear shifter around. I then go to the electrical cabinet in the rear and engage the starter switch located there and it starts. In my case the neutral switch is just not working as designed in those circumstances. The rear start switch is any easy check on the neutral safety switch. You need to make really sure you have the shifter in neutral and the parking brakes are engaged if you use the rear switch or you could end up chasing your coach down on foot. As far as I know the neutral safety switch is the only switch in the start circuit downstream of the key.

If this above doesn't produce the desired outcome then you need to check the voltage on the terminals of the start solenoid in the rear electrical compartment and if that is operating (you should hear it click as the key is moved to START) OK you will then need to check the solenoid on the starter itself.

If when you turn the key to ON you see no response from the gauges then you have a problem with either the key switch or the power supply to the the key which could originate as far back as the batteries.