Onan generator using a lot of fuel

[jointventure77]

Sent: 17/04/2006 

is burning 1 gallon of fuel in 1 hour and 10 min at 2500 watts in a 5000 wat onan genset 1972 model normal or do i need to lean the carb out..the plugs do look sooty?

[denisondc]

Sent: 19/04/2006

My 2.5kw onan seems to burn about .5 gallons per hour, running close to its rated output, maybe 2 kw. So a 5kw unit would be expected to burn twice as much, running a 4 kw load.

I would make Certain the ignition timing was accurate before I adjusted the carb settings to change them. If you are lucky enough to have the breaker type ignition points you can disconnect the points from the coil, and use an ohmeter to seek where the flywheel is when the points open - by turning the flywheel very slowly.

I wont guess how many degrees before TDC they should open though, you might send an email to Onan and ask. www.onan.com. Or walk into the nearest Onan parts and service facility - the website can help you find them by zip code I think
.
Points normally open later and later as they wear - and the plug wouldnt stay clean and light brown. My genset was running a little weak with the points probably opening no more than .010, instead of the .020 they should have been. As far as I know I replaced the original points and original spark plug on my 1972 LK model, in 2004!