I think this thread pretty well says it all about the starting system, except for one solenoid previously undiscussed. -- The intermediate solenoid.
At least on the mid to late '80's MH's, there is a solenoid mounted under the dog house, towards the forward right hand corner, bolted to the oil dipstick tube.
The purpose of this solenoid is to insure a full
12 volt signal gets to the starter solenoid. The theory being that miscelaneous losses amount to almost 2 volts up to the ignition switch, and, for the current required by the starter solenoid, another 2 volts is lost at the switch.
Since I installed the new 9800 series High Torque mini starter (the 9000 gave up the ghost after a very short time, traded the old 9000 in on warranty for the 9800), I hadn't experienced starting problems, until recently. I am not ready to tear out the old dash and replace it with a new one yet, so I was investigating alternatives to replacing the $25 dollar ignition switch I had suspected of causing the gremlin. With the dog house off, I could tell the intermediate solenoid appeared to be working, because of the loud "click" when attempting to activate the starter, but the starter was not engaging. Hmmm.....
Turns out the intermediate solenoid was not making internal contact, and a new one was had for less than ten bucks. Caution when replacing a "NAPA" brand, the small contacts are not for the same useage as the original GM and a replacement "Autozone" (Ford type). I lost more than a few minutes figuring out that one of the terminals on the "NAPA" replacement was not used, the one I thought was to be grounded was actually for the "hot" lead from the ignition switch, and that the stud diameters were different sizes (had to drill out the crimp type terminal connection to make it fit). This solenoid could contribute to the "hot start" difficulties, since it is subject to heat soaking up under the doghouse.
This is the same type of solenoid that the "hot jumper" (jumps the coach batteries to the chassis battery with a switch in the glove box) uses. The "Hot Jumper" solenoid is located behind the battery drawer. Add this solenoid to the list of recommended "spares".
This solenoid is used at least at two separate points on the coach, possibly three, if your Generator is equipped with a simple contact type starter solenoid.