Battery Isolator Hook-up

[krl13]

Hello,
I'm installing a battery isolator in my '92 F250 LB, Reg. Cab, a/t, 4X4. This is for the aux battery in my slide-in camper.

1) Where is the "easiest", under hood, tie-in to a 12V accessory source activated by the ignition system? (The "easiest" that will do the job safely and effectively.) What is the color code for that tie-in if it's a wire splice?

2) Best ground connection on chassis?

Thank you.

 

[DNFXDLI]

I'm not sure on the color, but the best ground will be run back to the battery.
You also might want to reconsider using a diode isolator as there is always a forward voltage drop associated with them which can affect charging voltage.
A continuous duty solenoid that is ignition switched would give the best results.

 

[krl13]

I stand corrected ... I am using a solenoid, not an isolator. Made that decision based on research here (as well as other).

So a ground to the battery is better than to the vehicle chassis? Battery ground would be easier as well. Curious as to why the instructions with the solenoid specify chassis ground?

Someone please suggest an easy access "key on" ignition source to activate the solenoid.

Thanks

 

[DNFXDLI]

Instructions would say chassis ground for ease in installation...nothing wrong with it if it's done correctly, however you are relying on the factory wiring which could be in great shape to crappy shape.
I have wiring diagrams for 1989...give me a bit and I will see what I can find.

 

[krl13]

I was planning on running a ground wire from aux batt and another from the solenoid directly to the frame. That way, the only truck wiring I'll be relying on is the switched ignition.

Thanks for you help on this. I'll be looking for the wiring diagram, when you can get to it.
Ken

 

[DNFXDLI]

I will get to it sometime this weekend....you might want to check the secondary cab/frame ground connections....I know on the 73-79's that there were some solid connections (batt to rad support) and some ones that relied on a pressure type clip with flexible braided conductor...and you are more than welcome for the help...

 

[DNFXDLI]

I'm assuming an EOAD transmission?...I'm asking as each diagram is different...and I am also assuming that the wiring will be close being a different year.

 

[krl13]

Correct. EOAD trans with a 351W