Generac GP7000E Generator outputting only 110v

[ILENGINE]

Star got ahold of a MM that measures capacitance... 27.52uf so it's good.

I asked neighbor more questions and he said the engine ran "rough" and he and electrician could only test generator with 1/2 throttle???

I'm gonna pick up on ILENGINE suggestion and go to engine side. Neighbor said the gas has plenty of Stabil in gas and I suspect that "plenty" may be the issue.

Gonna drain gas and put some of my own in a see what happens.

The generator was stored in cellar and always drained the tank and had regular maintenance. It literally looks like it just came out of the box.

If that new meter will test frequency put it on that setting and insert the leads into the outlet. if getting around 30 hertz instead of 60 you most likely found the issue.

 

[oldlawnguy]

If that new meter will test frequency put it on that setting and insert the leads into the outlet. if getting around 30 hertz instead of 60 you most likely found the issue.

It does... was playing with new toy settings and placed into wall outlet by couch and got a 121v @ 59Hz reading. If it's around 30Hz, you saved me from draining gas (not much in tank).

I'll add some and let it run a while and see if it settles down and then take another reading.

Thanks for the tip ILENGINE!

 

[oldlawnguy]

It does... was playing with new toy settings and placed into wall outlet by couch and got a 121v @ 59Hz reading. If it's around 30Hz, you saved me from draining gas (not much in tank).

I'll add some and let it run a while and see if it settles down and then take another reading.

Thanks for the tip ILENGINE!

Added my own gas and started up Generac and she ran rough (3500 rpms) for 5 min then settled down.
Tach reading 3660 rpms at full throttle no load
Measured fluctating readings of 99-110v all at 60.x-61Hz

Head scratcher, any tips on what to try next???

For comparison fired up my own generator;
Tach reading 3660 rpms at full throttle no load
Measured reading of 125v all at 60.x-61Hz

 

[oldlawnguy]

It does... was playing with new toy settings and placed into wall outlet by couch and got a 121v @ 59Hz reading. If it's around 30Hz, you saved me from draining gas (not much in tank).

I'll add some and let it run a while and see if it settles down and then take another reading.

Thanks for the tip ILENGINE!

If that new meter will test frequency put it on that setting and insert the leads into the outlet. if getting around 30 hertz instead of 60 you most likely found the issue.

Added my own gas and started up Generac and she ran rough (3500 rpms) for 5 min then settled down.
Tach reading 3660 rpms at full throttle no load
Measured fluctating readings of 99-110v all at 60.x-61Hz

Head scratcher, any tips on what to try next???

For comparison fired up my own generator;
Tach reading 3660 rpms at full throttle no load
Measured reading of 125v all at 60.x-61Hz

 

[ILENGINE]

Added my own gas and started up Generac and she ran rough (3500 rpms) for 5 min then settled down.
Tach reading 3660 rpms at full throttle no load
Measured fluctating readings of 99-110v all at 60.x-61Hz

Head scratcher, any tips on what to try next???

For comparison fired up my own generator;
Tach reading 3660 rpms at full throttle no load
Measured reading of 125v all at 60.x-61Hz

That frequency says that the engine is at the correct rpm. Could still be a voltage regulator issue, but could be other issues like brush contact issues on the slip rings if this model has brushes. Also could be issue with the rotor, which you don't want to get into. ie $$$$$$$

 

[StarTech]

 

[oldlawnguy]

That frequency says that the engine is at the correct rpm. Could still be a voltage regulator issue, but could be other issues like brush contact issues on the slip rings if this model has brushes. Also could be issue with the rotor, which you don't want to get into. ie $$$$$$$

 

[oldlawnguy]

Yup Star beat me it's brushless. Anything to try to eliminate the rotor and focus back to voltage regular which I confirmed its within 29uf spec???

Thanks!

 

[oldlawnguy]

View attachment 62667

DId some more poking around on help sites,

for a brushless alternator: troubleshooting test is to disconnect capacitor and connect MM to the 2 alternator leads and measure running AC voltage. If it measures 5v it's good and capacitor is bad.

If not 5v then alternator is bad and Generac wants you to buy a new generator at that price!!!! Maybe they design them to fail after x hours? :^(

 

[oldlawnguy]

DId some more poking around on help sites,

for a brushless alternator: troubleshooting test is to disconnect capacitor and connect MM to the 2 alternator leads and measure running AC voltage. If it measures 5v it's good and capacitor is bad.

If not 5v then alternator is bad and Generac wants you to buy a new generator at that price!!!! Maybe they design them to fail after x hours? :^(

I measured the out of the alternator on 2 different MM and got 3.5v and 3.7v AC
A 5v +/- 2v AC should be a indicator of alternator working. Measured voltage regulator again and got 27.5 uF

Put on my dunce cap. I was hoping to get to root cause, but still scorching my head. Any ideas fellas?

Thanks!