GX390 voltage regulator

I just brought home a new Honda GX390 electric start from Northern Tool. Packaged in the box was what I think is a voltage regulator. What’s the purpose of this & do I need it if I am using a 12v battery for starting?

I happen to have on hand a deep cycle 12v 125ah battery. Was planning to use that to power the starter on the 390, my electric hose reels & maybe some lighting. My assumption was I could just run a power wire from the + on the solenoid to the + on the battery (and - to ground). Just not sure where this voltage regulator comes in. Thanks for any tips.

PS - I don’t think I need the 390 to charge the battery … if that’s part of the equation. Pretty sure it has plenty of capacity to only be charged when parked at home.

Attach it to your skid and hook it up.

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Don’t know about a regulator. But, make sure you hook up the rectifier or you will have to charge the battery at the end of every day, of the battery lasts that long.

Yup, it’s a combo regulator/rectifier. I just didn’t know if the starter would work without it. Just tested it, and as most of you experienced guys probably know, starter works just fine with or without. But if you don’t hook it up you don’t get any juice back to the battery.

That engine comes with 18amp alternator. alternator to voltage regulator to battery. If you’re using the engine much it should keep battery charged pretty well, you may never need to home charge. I run 2 batteries in parallel on my truck build and I’ve never had to manually charge my batteries and I use my 12v a lot.

That is good to know. You get pretty good life out of a battery? Really I was just wondering if the charge coil on the motor is as electronically “smart” as trickle charger.

I don’t have much experience, but the only 12v system I set up in the past had solar panels charging a pair of 12v batteries. Rather than going straight from panels to battery, you put an electronic controller in between. That device senses the voltage on either side and sends only what is best to the batteries. Was just wondering if there’s any benefit to having something like that between the charge coil on the motor and the battery.

*I’m probably way over thinking things.

PS - I looked at the Honda tech manual and it specs 4GA wire between the solenoid and battery. Are you all running that heavy of wire?