Onan Generator help
Onan diesel generator HDKAJ-H. Throwing a code 31. (Overrevving), but I don't think the governor is the problem (Repair manual points to governor). At idle, engine runs great. Put a meter on the output and get 120V, but freq is nuts. Hz fluctuates from 500 to 2000 and all over the lot. Apply a little load (hair drier on cool and low) and its OK at 120V, but Hz still fluctuates. Apply higher load (hair drier on hot and hi) and it tries to spool up to accomodate the load (doesn't run away or anything), and shuts down with 31 code. I somehow think the Hz running away is coupled to the Overrevving error code. Maybe a sensor out? Control board?