Bought a used toy hauler that sat more the last 3 years then was used.  But owner just had Onan 4000 Carb rebuilt before Covid but the trailer been sitting since Vid started.  Well today I got to working on the Gen and pulled the fuel line to Carb, hooked up fresh gas with a serious amount of Seafoam and the gen fired up immediately. Ran the gen for about 30 mins constantly topping off my make shift fuel source.  I plan on getting the old gas pumped out of the tank then filling with fresh stuff with a ton of Seafoam for good measure.  But How do I get fuel from the gas tank in the rear of this 28' all the way to the front where gen is located?  I cant imagine holding down the primer button for a very long time is a good idea.  Any ideas is greatly appreciated.