ONAN MARQUIS 5500 GENERATOR

How much gas do you have in the tank. Has to be over a 1/4 tank.

How many hours on Genset and what Year Motorhome. Doug

Those were the symptoms when my fuel pump went bad.
Assuming you have enough gas in the tank

Thanks for all the information;
I have 1998 Holiday Rambler Endeavor (very good condition, kept in my pole barn.)
I have ordered a fuel pump and carburetor. 25 years old "it's time"
I have a good friend/mechanic.
Updates:
New cooling unit on back of refrigerator.
New 10 gal. hot water heater.
New transmission.
New circuit boards. (Hydraulic leveling board, Temp. control for air and heat, control board for holding tanks)
It is 460 Ford engine and I get 8 mpg driving at 50 in cruise control.
Thanks for listening (smile)

As noted, make sure your gas tank has enough in it to supply the generator. The symptoms you're describing sound like it's just running out of fuel.

An easy way to determine if running out of fuel. When it stops, when restarting, Does if fire within 2 to 5 seconds or even run shortly. If so, fuel starvation is NOT the cause. The carb bowl will run a genset for 30 to 90 seconds. You did not state HOURS on Genset. But your symptoms show Fuel/Carb gummed up. Since you have a carb on order, replace it FIRST, then run the genset. If it runs correctly send the fuel pump back. Another cause on Gensets that are at least 10 years old and older, the rubber fuel line from the Gasoline tank is probably dry rotted and sucking air, which WILL cause fuel starvation. The FIRST thing you do when having this type problem on an older genset is to connect a gallon gas can DIRECT to the fuel inlet on the Genset with a rubber fuel line. IF the genset runs correctly, now you have the fun of replacing the rotted fuel line from the Tank to the Genset. Doug

The gas tank is between 3/4 and full.
I will check rubber fuel line and probably replace it regardless.
Thanks