Portable generator problem

I have two portable gens (one 5500watts/one 6600watts). When I plugged in the portable air compressor Sunday the 6600 watt struggled to run and it smelled like the brushes were burning. When I used the 5500 watt the compressor worked normally (filled up shut-off, etc). Where should I start to figure out the problem? Thanks!

Were both instances a start from zero tank pressure?

Remove the back cover of the generator.Look at the windings. If they are black or a dark brown. They are most likely shorted.What generator do you have.


Generator tech for over forty years.

yes
not that it should make any difference..the 6600 is propane - the 5500 gasoline

6600 is a yamaha
5500 is a colman with a yamaha engine

Yamaha is a pretty good unit. Unless it is real old. It should not have brushes. Should have a terminal strip. Where the wires for output join up. Check for loose connections.As I said take a look at the rotor and stator windings. If they are dark,most common is a short.May not be worth fixing.

What Model is it. With model and serial number. I can bring up a print and check out sheet.

I have an electric start honda 4500 belt drive starter is junk any other starters that would fit???

runwolfe,
My air compressor sits in an unheated garage. It struggles to start when it's cold. I would suggest changing oil to a 5w-30.

It was around 30 and I tried starting my generator, which is a rope start. Had a heck of a time getting it started. After it warmed up I changed oil to 5w-30. What a big difference.

You may want to read up on your generator. Your motor's lock rotor amps may be larger than your genny can safely handle

If my only way were to power up an air compressor is with a generator, I would find the smallest pulley I could get for the motor. Then I would loosen the belt a little, let it slip on start. A belt is cheaper to replace than a generator.

Can't help you much with fixing your generator.

I know I shouldn't mention this because it will definately cause a stir, but I will. I power factored my 3/4 hp well pump. It took 200 MFD's to get the job done. I had a bucket full of used capacitors, so it didn't cost me anything. If you are friends with a HVAC man, he can get you used ones from units they scrap out. It would cost you a pant load to buy new ones to do your job.

My well pump used 12.5 amps before I added the capacitors. Now it draws close to 9 amps. In MHO, my generator seems to start the pump much easier. Some people may say not to do what I did. I would definately power factor an air compressor and see if it helps the generator. Can't see how it would hurt. I power factored my pump, not to save money from the electric company which will be very little if any, but if I ever lose power, I want to use my generator to pump water.

George

George,

You bring up a good point. Power factor correction is needed if you are supplying Watts and VARS, but is not needed if the utility supplies them and you only pay for Watts.

David,
I did say your savings from the electric company will be very little if any.

I think it's helps my generator.
George

You will not save any money from utility by power factor correction if you pay for KW. Usually only industrial customers pay for KVA, so it is beneficial for them to add correction.

The generator must provide KVA, so it takes fuel regardless of who generates. The earlier meters where not complex enough for both, but now I do not know why utilities do not charge everyone for KVA.

David, Because it costs too much to measure the KVA.
George

What model Honda.

Billy, Thanks! It is brushless. YG6600DE

Serial # 250940 I think. I bought it new in 2004.

You are correct. With the compressor having run capacitors added to obtain .9 power factor or better. It will start better than a non corrected typical single phase induction motor of .6 to .7 at full load.

My PF measured .97.

Thanks give me some time to do some checking. Has it been working ok before. Because there was one that had a wire in the wrong position. Would burn out after some time.

has been working fine

ES 4500

is that 6600 on gas and a lot less on propane??

I do not understand the question