Secondary battery and isolator install complete!

[Matt Buffington]

Hi Gang! An update on my 1990 Burb secondary battery install.

Everything works now after installing a Cole-Hersey solenoid that splits the circuit from the starter battery secondary battery. The original solenoid was closed all the time, and so the secondary battery was engaged during startup....hence blowing my in-line fuses. Wow, it was tough for me to figure out, but very satisfying now that it's solved!

Thanks for the help ya'll gave me in terms of things to think about, etc!

A second battery tray was gotten from LCM; I had to move the evaporator and bolt it to the new tray. I bolted the ground to the front panel adjacent to the radiator; I found this point from a GM secondary battery install schematic, and I did a voltage drop test to determine its performance.

You can see the bright 4 gauge wire I used to connect the second battery; this will be split tubed to protect it and make everything match under the hood.

The fuses and solenoid are mounted to a piece of oak shelf (painted) and bolted to the factory jack crank handle hold down (in fact, I even used the original hold down to stabilize the mount).

Solenoid is grounded to firewall; activation line is from an ECM line that is acc-on (found this after probing about 15 possible locations!).

While trying to figure out the install of the second battery tray, I sanded and repainted the starter battery tray. Boy, that was needed! A total mess!

I also did the 'big three' upgrade while pursuing all this; truck just runs awesome.

Next up: TBI rebuild; get that back window to go up and down with the key; find a spare tire; install spod to distribute power; add fog lights and running lights...and I'll post the builds as I go along!

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

 

[HotRodPC]

2 very worthy upgrades.

 

[TubeTruck]

@Matt Buffington How's this been holding up? I just got on here to come look and see what some of you have done and I found this setup. My battery tray decided it didn't want to hold the battery anymore so I need a new one and thought I would buy the secondary tray and run a dual setup.

 

[RipTideTiger]

I recently did the dual battery and monitor on my 91 V1500 with the SPOD pulling from the secondary battery. Works great and glad I did since adding accessories will be a breeze. I'll see if I can get some pics up soon. Where are you mounting your switches?

 

[AuroraGirl]

is the purpose of second battery on a gas truck to have more amps for starting or to assist with load-applying devices like winches?

 

[75gmck25]

On my ‘75 the 2nd battery is for Camper power. With the ignition off the camper only draws power from the 2nd battery, and then the relay makes it start charging as soon as you start the truck. I assume it had a similar use if you added the towing package.

Bruce

 

[Matt Buffington]

Great to catch up on this thread. My secondary battery and isolator are working as planned. Just added a gang buss 8 distribution box and controller on the inside of the truck. I even found a new ‘portal’ through the firewall that I never saw reported anywhere on the internets! Just below the brake cable portal....there’s a rubber plug the carpet is connected too....well, that’s a hole through the firewall!

Finishing up the lights this weekend on our safari rack. Waiting on brackets now for the lights. Anyone tried running light wires from the roof into the engine bay without drilling holes? I’m gonna try down the inner door seam...but with 6 lights on the roof, I worry there will be too many wires. I may have to split some down the passenger side too!