gen rpm not stable

[MARANATHA]

Hi everybody,
Anybody out there having a problem on their 8KW onan diesel gen where rpm is not steady at all with or without load. I know rpm will change everytime there is changes in load and this is not my concern, i know it's normal. I didn't use a tachometer for rpm measurement but by hearing only and in comparison to my friend's same type of generator. Warranty I believe is over because my unit is more than two years old based on onan policy. Any help is highly appreciated. Tnx.

[nodine]

Quote:

Originally Posted by MARANATHA Hi everybody, Anybody out there having a problem on their 8KW onan diesel gen where rpm is not steady at all with or without load. I know rpm will change everytime there is changes in load and this is not my concern, i know it's normal. I didn't use a tachometer for rpm measurement but by hearing only and in comparison to my friend's same type of generator. Warranty I believe is over because my unit is more than two years old based on onan policy. Any help is highly appreciated. Tnx.

I don't think the hearing test, even compared to the same type generator is reliable. Each gen set would have to be operating under the exact same conditions. If you don't have a surge protector installed that measures both voltage and frequency from the gen set then get one of these and plug it into an outlet:
Amazon.com: TRC AECM20020-3-012 Electra Check Digital Monitor for all AC Power Sources, Black with White Face: Home Improvement
Run the generator and check both the voltage and frequency. If the frequency is out of range then you may very well have a load control problem with the generator and need to get to an Onan service center.

Bob

[Route 66]

My 7.5 Onan QD is very similar to yours and the only time the speed changes is when the load changes.

Since these are variable speed generators, the frequency is not speed dependent. These are DC generators which use an internal inverter to obtain AC.

It sounds like a trip to an Onan service center is in order.