Voltage issue with Kohler 5e generator

[Steve500dancer]

this weekend I had my boat out at an event and the generator was running fine and the air conditioning was on. I went and had a bite to eat and when I got back the generator was running and the air was off. The voltage meter on the panel showed 25volts. I checked the fuse and it was fine. For some reason I am not getting much if any voltage output from the generator. The generator only has 35 hours on it. It is a 2003 and had not been run in 5 years.

Any advice would be greatly appreciated

 

[KevinC]

If the generator was running fine but not putting out enough of a charge you will need to focus on the output side. Unfortunately these units like to run and not using them is worse than not.

-Kevin

 

[Steve500dancer]

Does it sound like a voltage regulator to you

 

[hottoddie]

There are diodes in the output end that can fail and cause reduced output. They can be a DIY project if you are handy. Voltage output is regulated by generator rpm not at voltage regulator.

 

[Steve500dancer]

I did increase the rpms of the generator and watched to see if I had a voltage increase and had absolutely no change in the voltage.

 

[Stee6043]

I don't know if this works on a Kohler but it will work on Westerbeke. Worth a shot.

Next time you're seeing 25 volts on the panel turn on your stove or hot water heater (make sure the water heater will call for heat, this does no good if you're water heater is fully hot). If a substantial load like your stove brings it back up to 110V it's your diodes...most likely. At least on a Beke it will be.

One short term (or long term) workaround for bad diodes is to always keep a load on the generator. This can be accomplished by keeping both AC units running...as in....meat locker temp settings. Don't ask me how I know

Once a generator with bad diodes has low-load, it'll drop voltage. And the bugger with the AC units is that once you see "low AC" they will not try to turn on the compressors again so it won't self correct. You need to keep the load constant.

Good luck!