Generator Problems and Choices

[caylor]

I have a decision to make. Recently my 5.5KW Coleman Powermate Generator crapped out on me. This really angers me as the unit has less than 100 hours of service time on it. The engine runs great but no power is being generated. I have replaced all the easy things, (brushes and capacitor) to see if that would get her running again, but still no power.

The generator was an emergency buy at a Big Box store after a large ice storm in East Texas several years ago to provide electricity to "necessary" items (icebox, freezer, a few lights).

Our property is on a dead end circuit of the rural electric company line, so we typically are one of the lasts ones repowered. During the ice storm mentioned above we were out of power for 7 days and 6 nights.

The generator cannot provde power to all of the "necessary" items in the house. Our hot water heater is electric so it cannot power it, the icebox and freezer. I found out from the ice storm that nothing breaks the survior spirit in 10 deg weather like not having hot water to take a shower with.

So with that background, here are my choices:
1) With the help of TBNers get some tips on possibly fixing or diagnosing the generator problem. (Cheapest)
1a) Take the generator in to a repair shop (Cheaper)
2) Buy a Genset/Welder combo (i.e. Miller Bobcat 250 w/ 10KW power) I have a lot of pipe fence to maintain, and would like to add on to it. Cost around $3000
3) Buy PTO Genset for Tractor. Cost?

What do y'all think?

 

[geneP]

Understand from the git-go here that I am not a generator expert. But I have read of them having to be "re-excited". The method I read about is to plug a corded reversible electric drill into the plug, depress the trigger and spin the drill in the reverse direction. This is supposed to excite the generator fields if that is the problem.

 

[EddieWalker]

Chris,

Not sure about your generator, but it sounds very similar to mine. I got one with the Briggs & Stratton engine, but otherwise it's a cheapy. The Teckemush engine (sp) is probably the only one cheaper than mine.

I don't have your concerns for power, though I did run it everyday for three months while building my house.

My theory was that I didn't want to spend the big money on a high end generator if it's only going to be used on ocassion. I wanted it portable. And I wanted to be able to plug in my welder if I had to fix something away from the shop.

My Home Depot refurbished one was around $300. If it only got 100 hours on it, I'd be satisfied. For the money, it's still pretty cheap.

I'd put on your list after repairing it, buying another cheap disposable one. It seems that everyone has them stocked up right now, and after Christmas, there should be some good deals out there.

Eddie

 

[Highbeam]

I would bring it to a guy and get an estimate for repair. He should know right away what is wrong and will offer some alternatives. I also have a coleman 5500/6850 that I use for my 225 stick welder plus emergency stuff. It works great but is loud.

 

[kevincook]

Unfortunately, I have a Coleman generator also. It is one of those things that I wish I never did. I have had it for about 10 years and use it very little. The first one I had failed after about 10 hours use. The bearing in one end of the rotor failed. Check to see if the field needs to be re-excited first before you bring it for service. The instructions should be in your owners manual.

Good Luck,
Kevin

 

[caylor]

Kevin,

Thanks for the response. I have re-excited many times. I re-excited first, replaced the brushes, re-excitied, replaced the capacitor, re-excited, and nothing exciting happened.

I have not tried the reverse spin on the corded drill, though I doubt the outcome will be any different than the ol'jump start with a 6/12V battery.

 

[techman]

Very unusual to "fail" like that. Since you have tried to re-excite it with out luck, let's assume that is not it. I would check the main windings with an ohmmeter (not running). You will need to get into the electrical box to get right to the winding connections. If the windings are not opened (we know that they are not shorted - it would lug the engine to it's knees if it was), the problem could be in the built-in circuit breaker. They are usually the el-cheapo push button style. Sitting for a long time exposed to the ambient weather changes could have resulted in moisture and corrosion in the breaker. Check it with the ohmmeter as well. Last possibility is that the exciter diodes are bad. Unusual that they would just fail, but could be. under $ 10 in parts.

paul

 

[caylor]

Kinda what I thought too. I replaced and re-excited as described above and stuck the Voltmeter into the outlets no good, I mashed the cheapy circuit breakers and inspected them to make sure they were not tripped, still no go.

I then disconnected the main connector plug from the generator to the outlets and measured for voltage there, nada. So no juice is getting to the outlets.

So here are my questions, how do you check the resistance of the windings? Where to I stick my leads on my multimeter to check the resistance? What is a good and bad resistance reading?

 

[1962]

sounds like you tried "flashing the fields". quite possibly something like highbeam said. i dont know how much of a do it yourselfer you are. but you can build one for alot less than new. gen heads are on ebay, and if you have a big enough engine around its almost finished. figure 2 horsepower per 1000 watts. i saw a few complete generators not long ago on ebay in texas, could save a bunch in shipping. or you could put a gen head to your tractor off the pto. the ones you buy set up for pto use seem a bit pricey. you could design your own pto set up with a gen head and some gear or pulley reduction and have plenty enough power to run the whole house. my 5000 watt coleman took a dump some years back, so i built my own, and am glad i did..

 

[caylor]

Maybe a little more history will help.

I loaned the generator to a buddy of mine. He came over and since I had not started it in a while, I started it to make sure I was not lending a boat anchor. It started and made power no problem. He loads up on the truck heads off. A couple of hours later, he called and said the generator "aint working. The engine runs but no juice." So he brought it back to me and we pulled it off the truck, started it and it produced power. I said he was crazy, he partially agreed.

So fast forward a couple of weeks, and we loose power from the Hurricane Rita left overs. I get the generator hooked up and plugged in it runs and makes power for a while, then all of a sudden the lights fade and I head outside.

The engine is there running like no tomorrow, but with no power production. Its late so we light the candles and make due w/o power for the night.

The next morning I start it again, but this time no juice. I pulled off the head and one of the brushes jumps out as the head has becomed detached from the wire holding it, and the spring shot it out. AHA! I say, no brush connection = no power generation. I replace the brushes excite, nothing, replace the capacitor, excite, nothing. And here I am on TBN wondering what to do.

Thanks in advance for you help