Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

When disaster strikes, my deep freezer goes down. Is were can a find a discotion about genarators? Thanks.

a 6.5hp generator is capable of just over 3kw of output.   I suspect that a decent 3,000 to 3500 watt generator will be adequate for your needs.  The freezer will not draw anywhere 2.4kw of power when running, it may have a fairly large starting load but no where near 2.4kw.  With a 3,000 or 3,500 watt generator you should also be able to run a tv, lights, computer and  maybe even a microwave.


Size the generator for you basic needs.   Big generators eat big amounts of fuel.   Most people can get by in emergency situations with 3,000 watts as long as you are not depending on it for heat, hot water or cooling

Carl

Why do you want to spend big bucks on a generator? Make one your self. 1. Go to a thrift store and get an old 3 hp engine. Make sure it runs good- it doesn't matter Horizontal or vertical engine. 2. Go to your local junkyard and get a car alt with built in voltage regulator, and a car battery 3. Go on line and get a 6000 watt inverter. 4. Make a mount for your engine and alt, then pulley them together. Google home made generator for more details. I built a sound cover for mine. It is as quiet as a Honda generator

Here you go 7hp 3,000 /3500 watts    319 dollars.  You really cant build it much cheaper even with junk yard parts and these generators are normally reliable and get pretty good reviews from consumers.

http://www.harborfreight.com/engines-generators/gas-engine-generators/7-hp-3050-rated-watts-3500-max-watts-gasoline-generator-67560.html

I was going to suggest the same thing. Don't get me wrong, I'm all for a DIY solution when appropriate. But there's also a point where, to me, it's either not worth it, or I may make something less-robust when doing it myself. To buy an inverter of that size seems to be ~$130-180 or so (I'm sure there are less-expensive options, this is just from some quick eBay checking). Plus an engine, plus an alternator, plus coming up with a way to mount it all together.

A 3hp engine, as an example, gets you a max of 2,200W, if everything is 100% efficient. Or you can buy something that will put out at least 3,000W, and not need to worry as much about something not working properly, and perhaps damaging what you plug into it. If you have the engine, and you have access to a big alternator, etc, it may be a great solution. And it would certainly be an interesting project. I'm not saying there's no place for it. But in some cases I'd prefer a commercial solution.

Frankly, a Harbor Freight unit wouldn't be my first choice from a quality perspective, though the capacity/$ is tough to beat for being new. And their small 800W generator appears to get very good reviews, and is as little as $90. But keeping an eye on Craigslist may get you a larger, higher-quality used unit for less than a new Harbor Freight. I bought a 5500W Generac (also puts out 220V) for $175, with pressurized lube and an oil filter. Replaced a bad oil pressure switch and it's worked great since. There are better deals out there, but I still got more machine for less $ than HF. And I don't think I could have built anything for that price. Just my perspective.

a 3hp gas engine is really only going to produce 1500 watts on a good day not counting the huge conversion losses using a 12v alternator (which in and of itself is quite inefficient)  to charge an lead acid battery to feed a DC/AC inverter which is at best 80% efficient will produce when all is said and done about 1,000 of useable power.

A pressure lubed 5500 watt Generac is a nice generator.  I suspect its an 11hp engine on it.  Yes if you can find one that is cheap enough on CL especially if it has carb problems and the gen head is good I say grab it.

Correct, it has an 11hp GN-320 Generac engine. It sounds like the portable Generac units aren't held in the highest regard (they certainly aren't Hondas), but the price was good, and it kept me going during the October storm we had (fridge, furnace, lights, and also the pump for the sewer line, though I shut off the fridge & furnace when running the 220V pump).

The only issue it has is that it surges unless I give it half-choke. It smooths out nicely with the choke. So my assumption is that the carb is running lean (whether due to being partially clogged, or if that's just how it is with today's gas, I don't know). The carb is not adjustable. I'm having trouble trying to find a rebuild kit for the carb, however. It's a Nikki carb, 093302 or 093302A. And I'm hesitant to open the carb without knowing I can get a rebuild kit. I can run it with partial choke. I can't run it at all if I damage a seal or whatever and can't replace it

Is that one of those plastic carbs.   I had to do some work on my Brother in laws generator that had an 11hp briggs on it and it surged very badly most of the time and need 1/2 choke to run correctly.  It was really strange because it didn't do it all the time.  You could start it up and run it and it was fine, turn it off and 2 hours it was surging when you ran it.   It had the plastic carb with the clip on the float bowl. 

I opened it up and cleaned everything very well but it still did it.  I told him to run it at 1/2 choke when it acted up as he did  not want to spend the money for a new carb.

I am pretty sure the carb is metal, going from memory, and pics of the carb when I've been looking online for rebuild kits. It's a Generac-built engine (well, maybe actually built by someone else, but pretty sure it's not a Briggs), for reference. It's an older unit, ~2000 or so, I believe. The carb is ~$65, so I don't want to just try replacing it. I'm OK with running it with partial choke for now, but I'd feel better if I didn't need to do that.

bus708 wrote:
That's a lot of parts of unknown condition and reliability.  Seems like increased probability of things going wrong when you really need the power.  If this homemade generator is a back up unit of the main generator, that's fine.  From the description of all the components, the overall size is going to be 3 to 4 times the size of a generator of equal wattage, just thinking out loud.

Do you have a picture of your homemade generator?

I must admit to running a homebrew backup generator.  My backup generator is based on single cylinder 6hp diesel engine that was designed in England 1929. This engine has two huge flywheels each weighing 150 lbs and was originally designed as a hand crank start. the engine weighs about 600 lbs and belt drives a large (250lb) 4 pole 1800 rpm 4kw gen head  The engine and generator are mounted to a very large I beam frame which weighs about 275 lbs by itself

The engine runs along at a nice slow speed 650 rpm and just kinda of lopes along.  no screaming 3600 rpm. 
My generator is currently setup to run on 85% natural gas and 15% diesel.

My generator is connected to a manual transfer switch which powers 20 circuits in my home.  During a power outage I start the generator and just flip the transfer switch to gen and we again have power in the house.