Onan Generators

[JPO]

Could this generator that has sit for 20 years have a lot of problems?  It was new when it was used last. It is a Onan Emerald III.

Thanks to you experts.

JPO

[thomasinnv]

what is it? gas, diesel or propane? that may make a difference. gas will gum up the carburetor in a short amount of time if not properly made ready for storage. diesel may begin to grow algae. propane one may dry out the diaphragm in the regulator. moisture is enemy of the alternator as well. really no way of knowing other than fire it up and put it under load.

[papatony]

I believe one sitting that long will proably have problems. A lot depends on what you have to pay for it .Onan parts are very expensive but there are sub parts for them. I can help some what, pm me with details. I just went thru this with one not near that old

[Ncbob]

Other than a carburetor problem (varniish from gasoline) I can't imagine that there could be much wrong. Take a wet and dry compression test before starting it and clean the carburetor with Trylene (take it off and soak it for a bit). Don't change any of the adjustments after you blow it dry and prime it with the electric fuel pump.

You might be pleasantly surprised. If I can help...PM me.

Bob

[TomC]

I had an 6.5 Onan Emerald III commercial unit with a PTO shaft coming out of the alternator that I ran an air conditioning compressor for my sleeper A/C on my over the road big truck.  The biggest complaint I had was with the carburetor.  I had to adjust it everytime I went up to altitude, then again when back down.  But-I always kept a load on it-always running my 1500 watt block heater when it was running.  I never had the heads off, and it ran 12,000 hours before seizing up.  Don't even goof with the carb-just go to Onan and buy a new one.  Most likely everything else on the generator should be alright.  Just check the starter-the newer ones have a starter solenoid on it.  The older ones were inertia drives that weren't reliable.  Good Luck, TomC