Generator trouble

[bigrockcandymountain]

I have a 7000w cheap chinese gas generator that I use for backup power for the house and other portable power.  It starts and runs great but lately it isn't really working.  It was running a 1500w heating element and suddenly started pulling the engine down and eventually quit.  Now when I run it even without a load connected it pulls the engine down. 

It isn't the usual fuel flow, plugged carb stuff.  I went through all that.  It seems like the engine is labouring.  Almost like a bearing seizing up, but not that because when you pull the cord immediately after shutdown, it spins freely.

 I am leaning toward a shorted generator winding, but there is no smoke or anything so I am not sure.  I know some of you guys are way better with generators than I am so fire away with suggestions. 

Also, any advice on testing the windings and other generator end components would be appreciated.

Thanks in advance
Derek

[MattM]

Did you check the oil level.  Generators built today kill when oil gets low and in some cases if its just opaque from use.

[dnix71]

Worn bearing on the gen. With the engine running, the slop is enough to allow the rotor and stator to touch, but not spinning there is no interference. Or the woodruff key has slipped/sheared and the engine timing is off.

[SparWeb]

Have you made any progress on this?

Have you removed the alternator to investigate it separately from the engine?

[bigrockcandymountain]

Nope, sorry.  We got to our busy time of year and i guess i pur this on the back burner.  I will hopefully get to it fairly soon.

[bigrockcandymountain]

So, here it is new years gone and i finally fixed this generator.  It was the spark arrestor screen in the muffler plugged full of carbon.  I pulled it out and it runs like new.

I might try to get a new one, since the old one went to pieces when i tried to clean it.  I may just run without one. We live in a very fire prone area, but I'm careful about fire to the extreme, so it would never get run anywhere near dry grass etc even with a spark arrestor. 

I'm almost positive i tried running without the muffler last time i looked at it, but i guess maybe I'll just have to say that i inhaled too much exhaust that day. 

[SparWeb]

Things like generators... you have to also consider the day you loan it to a neighbour or you have a helpful family member lending a hand with a project, and they start it up NOT knowing about some of your workarounds...  Still not likely to be the end of the world, but the chances are higher that something could go wrong because they won't be expecting it.

Wait a minute, don't you have a mobile generator in that welder you just got?  Boy a guy has to be either lucky or just really busy to need two mobile generator sets...

[bigrockcandymountain]

Point taken about lending it out etc. I'll try to find parts to fix it right. 

Ya the big welder makes a very nice genset.  I was actually thinking i might sell this one.