Need help adjusting frequency on Koehler 5E

2006 340 Sundancer

When I purchased the boat this May, the previous owner had to replace the carb. When we surveyed the generator ran great and the voltage was checked but the surveyor did not have his frequency meter and suggested I verify the speed was correct.

Fast forward - I really did not use the generator this summer other than run it with a load at the dock on occasion. I recently ran it with the air conditioning on to put a bigger load on it and noticed a sound which I can only describe as a slight squeal from the a/c unit. I wondered if the frequency was in fact off since there is no noise on shore power.

I borrowed a meter with HZ reading on it last night and saw it was at 58hz. I left the manual at home so I just raised the idle screw to see if it would raise. It did but fluctuates more that I expected.

What is correct method of checking and adjusting the frequency? The manual has me scratching my head. Should I have set it with no load? I noticed when I turned on the stock inverter the hz dropped to 56. Is there more than just the idle setting?

Thanks in advance,

Mark

 

The model is 5E. 3600 rpm.

Being more specific - the manual I have has very little for pictures and talks about setting pots to get 60 hz. I too assumed rpm will set frequency but am not sure if I’m supposed to adjust something other than the idle screw. With or without load? Etc.

How did you adjust yours and how did you verify it?

Thanks

 

Thanks Sky - where are these pots? My manual doesn’t really show them other than in schematic form. As mentioned above I do have the meter which is how I found out the frequency seemed low.

 

Thanks - that’s the same manual I have - I will try to follow this procedure later this week.
It’s weird that everything seems to work fine but that whine when running the ac must be due to the low frequency. My electrical engineers at work tell me if it was higher hz it would be less problematic. Hoping this weekend to fine tune it. I am still not sure why after the po did a carb change why I need to readjust frequency pots…. One of my engineers says it should only fluctuate +/- 1 hz.

 

To close this out (at least for now), I realized that the idle screw I was adjusting was just that, an idle screw. I noticed that the governor has a screw adjustment so I cranked that in a little and saw the frequency increase to where I was more comfortable. It’s not holding as steady as the shore power as sky noted, but it stayed up at the 61/59 HZ. I hoped for. I then checked the rpm and saw it was right on 3600 with this setting.
The final test and reason for my checking all this, was turning the a/c on and listening for the whining I noticed earlier. For whatever reason the noise is gone. I would like to believe the low frequency was the cause.

So after a few hours of run time I changed the oil, plus oil and gas filters, impeller, plugs and winterized it! Should be good for next year.

 

Not a bad idea - is there an easy access drain screw?

 

True -but at this point it already has antifreeze in it and the plugs have been sprayed with fogging oil. Ill try to drain it when I'm in there next.