70s Power Wagon Ignition switch info needed !!

[Mattax]

Ok well had way to much timing in engine which was addressed today.
Truck has a medium sized inverter installed @ REAR and noticed even with unit OFF while changing battery once wire leed was connected it sparked and must have been pulling enough on battery that once truck sets for a few days it's enough to drastically drain battery.
Appears all is well now and thanks for the professional advice etc.

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There's a few guys here with some experience dealing with second batteries.

You just answered your question as to why your alternator is constantly charging, The coach battery (or batteries) are shot. If your motorhome doesn't have a battery isolator you need to get one. I had chassis/coach batteries in 4 different tool trucks in 28 years of the tool business. @ trucks had isolators and 2 used a constant duty relay to charge the coach batteries. The isolator separates the 2 electrical systems and only charges the batteries that need the charge. Your engine start/chassis battery doesn't need much charge unless you are using the lights, heater, wipers, etc. If you use the camper for any length of time those batteries will need charged. With no isolator your system will charge one set and overcharge the other set. I had many battery and alternator failures because of overcharging in the trucks without a isolator.That bad coach battery will cause the system to overwork.

The Chassis Cab does indeed have an isolator....it's in one of the pics I posted. I tend to keep what the original engineers designed...

Had a crew that would work with the truck radio playing,and run it dead constantly.
It was equipped with an isolator and a second battery for a winch.
So they would use it to boost.
Smoked alternator and burned up several isolators. Finally the cause came out in a discussion,put an end to misssd diagnosis and comebacks.

 

[NCmtnDWELLER]

Correct !
Ballast resistor was fine and a spare in rear of vehicle with a few other parts for emergency situations. I had multiple issues
To much timing and a power inverter in rear even off was pulling down on battery corrected both problems gone thanks for the help from all.

 

[NCmtnDWELLER]

Ballast resistor is bypassed during start.**

How it works, using a points system for the example.

1. When the key is turned to start current flows through to the key switch and then splits,
a. Some current takes the path of the S2 wire (yellow) to the starter relay, through the neutral safety switch to ground.
b. Some current takes the path of the J3 wire (brown) to the coil whenever the distributor points are closed.

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Take your finger and trace the path to the coil.

The rest of the sequence to get the starter turning happens very quickly.
2. Power through the relay's bottom terminals internally connects the big stud to the solenoid terminal. Current flows from the battery to the starter's solenoid.
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3. The starter solenoid (inside the starter) closes and the starter draws battery battery power to spin it.
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The starter draws a lot of power.
Battery voltage will get pulled down during starting, but if it drops to 9 V its probably not going to start. Recharge the battery with a charger.


**With electronic ignition, the 1/2 ohm resistor is needed for the ECU to get power during start.
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Thank u