Military Vehicle Repair: Ten-oh-eight electric nightmare, shape block, chevy dealer

Question
Hello. I have one of those basically Chevrolet pickups referred to as ten-oh-eight. It has 2 alternators, 6.2 diesel engine, 4X4. Cool truck, but doesn't like to start when cold. Put a new starter on it and it spun like crazy, then quit cranking. Got another and did the same thing, then found that I need 24 volt starter. But the headlights are 12 volt, and the alternators are 12 volt. Whats the deal?

Answer
The M-1008 CUCV (commercial utility cargo vehicle)has a dual voltage system.  Both the batteries and the alternators are 12 volt, but they are hooked together in series to produce 24v for starting.  That's the military standard starting voltage. . . so now thw CUCV can jump start a HMMWV and so on.  Anyway, look on the firewall near the center, and you will see a diamond shape block.  that's where all the 12v systems draw power from.  It's kind of like the (+) post on a car battery.  The starting system draws from the (+) post on the battery that is farthest back.  Follow that cable to the starter.  It is 24v.  Yes it is a cool truck!  Very heavy-duty.  Glow plugs go out all the time, but the chevy dealer should carry them.  These trucks are still used to a very limited extent in the USMC.  If the Marines can't break them, it's a good truck!.