24 to 12 volt

[trucker 1954]

Cheapest way to reduce 24 volts to 13.5 volts for assy 1986 contract m128a1 thanks reelboys

 

[doghead]

need more info. What are you trying to power with 12 volts?

 

[trucker 1954]

sealed beam lights draw 12 amps each 385,000 candle power x 4

 

[doghead]

OK, now what is a M128A1?

1028a1, use the front battery for high amps or, or tap off the stud block near the brake booster on the firewall for something low draw.

 

[hobie237]

Just run them off one battery.

 

[Recovry4x4]

Since it's in the CUCV forum, I'm assuming he meant M1028A1. If he really means an M128A1, its a 12 tone semi van trailer with full width back doors. There is a 12V lug terminal just to the passenger side of the brake booster that has plenty of amperage however it is not switched with the ignition. You could hook your relay up to that to provide voltage and then switch he relay with power from one of the fuses under the dash. Use a 12V test light to determine which one has the power you need (accessory, ignition or constant).

 

[corelokt]

That sounds right. Tap into the front battery. Use a an inline fuse. I'd also use a relay, somthe lights can't be left on. Power the relay from a source that only has power when the keys on. I installed a whole acc. fuse box this way, and have since found use for all the outputs on it.