Starting Gas Generator with Car Battery or LiFePO4 Battery

[Berdink]

My little battery is dead that starts my WEN 4750 Gas Generator.
It is a 12v 7ah battery. I don't see any markings on it that specifies the cranking amps.
I Googled asking if I could start a 4000W Generator with a 12v car battery, and it said Yes.
A new 12v 7ah battery is around $40 dollars.
Anyone have any input on if it's okay to start a gas generator with a typical lead acid 12v car battery?

 

[Berdink]

I did find this:
"A 4000-watt generator starter typically requires 350-400 cold-cranking amps (CCA), with the exact amount depending on the specific engine model and temperature.

 

[Berdink]

Then I googled whether a 12 volt battery can have too much cranking amps, and I got this answer:

"No, a 12-volt battery with too high of a cranking amp rating will not damage your vehicle because the starter motor only draws the amperage it needs.

 

[DIYrich]

Then I googled whether a 12 volt battery can have too much cranking amps, and I got this answer:

"No, a 12-volt battery with too high of a cranking amp rating will not damage your vehicle because the starter motor only draws the amperage it needs.

This. Yes, you can use a 12v car battery to start the generator.

 

[Berdink]

This. Yes, you can use a 12v car battery to start the generator.

Thanks!
It makes no sense to buy another lead acid 7ah battery for a starter battery for $40. I'd be better off buying the cheapest lifepo4 for the few occasions I use the generator.

 

[MakeMePower]

Thanks!
It makes no sense to buy another lead acid 7ah battery for a starter battery for $40. I'd be better off buying the cheapest lifepo4 for the few occasions I use the generator.

i actually use a lithium jump starter, I don't even use a battery anymore.

 

[doing it different]

Most of those lead acid atv and lawn mower batteries are completely trash.
Last maybe a year or two.
Some of those generator have gel cells.
Imo total trash. Yes you can boost it or just extend the battery leads and hook up any 12v battery. Even a bigger 12v lithium probably will start it. The 100A bms is the limiting factor

 

[jimf909]

Thanks!
It makes no sense to buy another lead acid 7ah battery for a starter battery for $40. I'd be better off buying the cheapest lifepo4 for the few occasions I use the generator.

As long as you won't use it below the low-temp discharge protection turns off the battery.

A car starter lead-acid battery will gladly start the generator many, many times regardless of temp.

If you use the generator just a few times a year you may consider just using the pull start instead of worrying about a battery.

FWIW, YMMV.

 

[dopeassjackson]

My champion came with a lithium starting battery. It dosnt start the engine below about 27*f. This kind of sucks because it's in a shed 80' from my cabin and has remote start. When I replace it it will be with a standard lawnmower battery.

 

[Dagoth Ur Does Solar]

Making me curious what kind of lead acid battery came on my Champion.

I've been using a Battery Tender on it since I got it, whenever it's not in use it's connected in the storage building to the maintainer.

It has a pull start as well, so if the battery did ever die, I have that. But I do like the idea of just using one of the lithium ion jump packs to fire it up if I needed to in a pinch!

It's gotta turn over for several 5 second intervals to fire up if I'm starting it up from scratch on natural gas. I assume it's mostly purging air from the line. Wouldn't want to do that in the freezing cold with the pull starter!

 

[Berdink]

Reporting back...
.
I hooked up the car battery and it worked as said.
.
When running, the wires for the battery from the generator put out 19.5 Volts DC.
.
Would it be safe to charge a LiFePO4 battery wired to it?
I'm guessing only if I route it through a charge controller.

 

[cs1234]

Reporting back...
.
I hooked up the car battery and it worked as said.
.
When running, the wires for the battery from the generator put out 19.5 Volts DC.
.
Would it be safe to charge a LiFePO4 battery wired to it?
I'm guessing only if I route it through a charge controller.

Use a charge controller.. a lifepo4 isn't going to like 19.5vdc.