Cummins Onan 5500 question

DryCamper11 wrote:

JSS1439 wrote:
Hey DryCamper11, I adjusted that governor spring in both directions 3 notches and couldn't tell a difference. Any other suggestions that may help the "hunting" at low loads?

If it made no difference - set it back to where it was, then go through the troubleshooting section of the manual. I've got two Onans with the manual governor and one step in the setup is to adjust the position of that spring to increase sensitivity until it begins to hunt, then back it off until hunting stops. I find that hunting occurs most often at low power levels, and over the time, as the gen ages, I occasionally have to readjust it by moving it towards the end (away from the pivot shaft). That reduces sensitivity and decreases the tendency to hunt.

You can try moving the spring all the way to the far end to see if it stops hunting (just as a test), but that shouldn't be necessary in normal use.

If it's not a hunting problem, make sure you've disconnected all loads. I once saw a problem that looked like hunting, but it turned out to be a load that would start up, the gen would go full throttle trying to power that load, but before the gen could stabilize, the device would decide the voltage was too low and would shut off, so the gen would go back to idle. The cycle would repeat.

A microwave on partial power can make the gen do this, too, as the microwave cycles on/off to limit power.