Onan Quiet Diesel Generator

[Bob (WA0MQE)]

I have an 8KW Quiet Diesel generator that seems to surge up and down when it runs. I can understand it doing this when it's powering a heavy load, but it seems to do it any time it's running. Does this seem normal?

[bluepill]

Mine is very stable. The RPMs increase only when a load is added. If you have an ammeter you can check to see if some load is switching on and off.

[dons2346]

You might have some load being applied that you don't know about. You can see if it is a load or a generator problem by flipping off the breakers on the generator while it is running. That will remove all loads from it.

[pwhittle]

The RPM's won't change with load, but the amount of diesel being put into the engine will increase under load to maintain the correct speed to provide 50 Hz. This will make the engine sound different under load than no load.

Paul

[Rex]

Change the fuel filter.

[Mr_D]

Quote:

Originally Posted by pwhittle The RPM's won't change with load, but the amount of diesel being put into the engine will increase under load to maintain the correct speed to provide 50 Hz. This will make the engine sound different under load than no load. Paul

Some of the Onan's do in fact vary their RPM with the load between 1,800 and 3,600 RPM. Some do not. You can go to the Onan site and look at the specs.

We have a Power Tech 8KW, it has a Kubota 3 cyl engine. It runs at a constant 1,800 RPM, and takes .72 GPH at full load.

[pwhittle]

I was not aware of that. My Onan gas generator was governed to produce the correct frequency. My Kohler diesel generator uses the same principal.

Thanks for the info. I learned something new!

Paul

[hardy1000]

Quote:

Originally Posted by Rex Change the fuel filter.

Ditto

[dons2346]

Well, how does it run now?