Small generator

What is the smallest gas powered generator they make??
Something that only puts out 12 to 14 volts and 60 to 90 amps is big enough.

A car alternator would even work if I could figure out a way to hook up a small light weight gas motor to run it.

The issue is not your 12 volts, the issue is 60+ amps. That will take 4 or 5 horse power to spin a Delco alternator. (not small) it will also need a battery to control charging voltage. If you need starting type current, a group 24 car battery will be cheap. Wire it up like it was on a Farmall. Bob M's diagrams will do it, just ignore the ignition system. JimN

While on the farm I once rigged up a Smaller 12v alternator to use as a battery charger. It worked fine but was not as big as they have now days. I think it was a 1/2 HP electric motor I had on it but am not sure, it could have been a 3/4 HP. The motor handled it fine but I don't think it put out more than 30 amps. I had the regulator from the same car hooked up to it. I had the quik spring type connectors on the wires that go to the battery. I think in this setup you have to have it hooked to a battery to run it or you may burn out the alternator, not sure about this either. I know on the old style 6v generators they said to never run it without a battery.
Anyway, with this system you would have 12v power. You just need a bigger alernator and a motor big enough to handle it,I would think a 3/4 or 1HP would do it or else a 1 1/2 would.

I have a battery so that is not a problem.

I was looking for something to charge it while I was camping. Have been looking at one of these 1000 watt generators because some of them also have 12v but have not searched it enough to see how many amps they put out.

Neighbor took an old push mower, took the blade off and put a pulley on, cut a slot in the mower deck and bolted a car alternator on it hooked up with a v belt. I even think he had a battery box on the deck with a small car battery. Nice small, portable unit. Good luck! joe

I have done three of these. What I like best is to use an old tiller frame that used a % hp vertical shaft motor. If you can find on with a bad gear box, remove gear box and install the alternator there. You need a bigger pulley on the engine. I buy a cheap set of booster cables for the cabling.

Kent

One of my crop adjusters said their local Aldi's grocery store was selling 3500 watt generators with a Honda knock off engine for $200. Several of his neighbors had them and liked them. For $200 you couldn't hardly mess with making one.

Plus he said they were real quiet.

Good luck,, Gene

When you say "small", I'm not sure if you need something portable and light. A Delco automotive generator hooked to a 4-stroke-cycle gas engine is not going to be light. That sort of setup does make a cheap, reliable, DC genset though. Many have been homemade for years to charge solar-electric battery banks. 90 amps, however, is a lot. If you used an automotive 100 amp alternator and worked it full-time at 90 amps, you'd burn it out pretty fast. If you need steady 90 amps, you need a 150 or 200 amp automotive alternator - e.g. a Leece Neville or eqivalent.

Smallest factory made gas generator I've seen were made by Coleman and Subaru. A few years ago, Subaru had a really nice 400 watt gas-powered generator. It was a promotion for awhile and most Subaru car dealers had them in the showroom.
It weighed around around 15 lbs.

Coleman also sold several small ones for camping. A 350 watt, a 400 watt, and a larger 700 watt. I have one of the 700 watt units. Has a very quiet two-stoke-cycle gas engine, puts out 700 watts full time and 1000 watts surge. Weighs 22 pounds. It is also inverter based, so can put out power at very low RPMs. Coleman is out of business, so it would take a search to find one. Building supply place near me still has a new one on the shelf. It is Model PM0301010

By the way, another poster mentioned the Aldi store and the 3250 watt generators they just had on sale. I bought three. It's a fanstastic deal. Brand new, full warranty, and $199.99 each. Has a 6.5 horse overhead valve gas engine. 3250 watt surge and 2500 watt full time. AC and DC. Chinese made with the King Kraft name-tag.

I also have a 1000 watt genset I bought there last year - again - overhead valve gas engine, but 750 watts full time and 1000 watt surge. AC/DC. Paid $139 brand new and I've used it a lot. Nice little rig. Chinese yes. But, if it breaks down tomorrow, it owes me nothing. Go price a similar sized Honda.

I've got several DC only genests laying around - a bit bigger than you want.

I have a brand new, never run gas and LP DC only genset with an industrial grade 8 horse Subaru engine. Pow’r Gard - company now owned by Baldor. The head is: 3 KW max, 2.4 KW sustained. 67 amps at 36 VDC. Built
USA in Oshkosh, WI. P/N 12.00025
Engine - Subaru EH25. 8 horsepower. SFJ251U1G2RA 251 c.c.
Regulator - Input - 180-270 VAC 50-60 HZ. Output - 63 VDC and 2 amps DC. Basler
S/N H00053022

I also have a used small DC gas genset -One cylinder electric generator. United States Motor Corp. Oskosh, Wisconsin. Model
AT&T specs. - 285-B-50 Ser. # 317762 Watts - 825, Volts - 115 DC, 7.5 amps.
Briggs and Stratton engine model 6FB, typ 106524. Has four 110 outlets and one standard
lightbulb socket.

Also have a used military gas-engine, DC only genset. Military Continental two cylinder gas engine electric generator. The engine is 16 c.i.” and is a Continental. Stock # FSN - 2805 - 072 - 4871. Ser.# N-001972. Continental Motor manuf. 3/64 Military model 2A016 III 28 volts
DC, 53.5 amps.

There is an electrical formula which may help you.

Volts multiplied by amps equals watts. If you have any two portions of the equation you can determine the third by division or multiplication.

So if you have a 1000 watt generator putting out 110 volts the amps would be 9.09. If the rating is for 120 volts the amps would be 8.33. If the 1000 watts were being produced by a twelve volt inverter there would need to be an 83 amp input.

V X A = W Watts will always be the bigger number so it is easy to remember the formula.

For a tad more info, 1000 watts is a kilowatt and when used for one hour becomes a kilowatt hour or KWH as on your light bill.

Not quite sure how much you might tie up in your project but Harbor Freight has two generators listed for less than $200. If you have a retail store near you it would save shipping. My Ace Hardware store sometimes has cheap generators in stock, might check there.

You can get those little orange generators with the knock-off Honda engines for about 150 bucks around here. Our fire dept. got one... about 1200 watt I think. It's definitely no more. Seems to work like a Honda. Dunno how long it'll last though. Quiet, fairly efficient. Good enough to run 2 of the 500W flood lights which is all we wanted it for.
It seems to me that most portable generators of that vein have a 12V battery charging receptacle and I think most all are limited to 10 amp or thereabouts. There would be no advantage to a larger generator from that perspective since it's the circuit that's limited, not the gen itself.
This one is light and easy to toss around. So far, so good.

Rod

www.ruralking.com has a TG-1200 generator [1000 watt] in their latest flyer that came with the Farm World magazine. Cost-$99.99 Could be real handy .