Pumping fresh gas to Generator 28' TH

JBL

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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.

 
you could just connect a evacuator to the fuel line and suck it up. or put a little oil in the fuel pump first and hold the button. or pull the fuel line to the ground and start a syphon.   pressurize the fuel tank  

 
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Pressurize the tank with compressed air it will not take much pressure

 
If you do put pressure to the tank. 
Remember to just let the pressure in the tank to release SLOWLY. If not you will be wearing the gas.  Trust me on this. 

 
How much fuel is in the tank?  I would just put twice the recommended sea foam in the tank and top it off with 91 and run it. just keep topping it off every time you use it.  till about half way thru your season. at that point run it down to close to empty or around 1/4 tank. Then at that point sea foam or Stabil the fuel as you put it in. 

 
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.
Probably overthinking this.  The carb is vented anyway, so fuel will flow down that line until it reaches equilibrium with the level  in the tank.  The prime shouldn't have to run to pull gas all the way from the tank.

That being said, I've seen plenty of people in camp do exactly that for 30 seconds to a minute for many a trip, don't think I've ever seen a bad Onan fuel pump.

 
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Probably overthinking this.  The carb is vented anyway, so fuel will flow down that line until it reaches equilibrium with the level  in the tank.  The prime shouldn't have to run to pull gas all the way from the tank.

That being said, I've seen plenty of people in camp do exactly that for 30 seconds to a minute for many a trip, don't think I've ever seen a bad Onan fuel pump.
Can't tell you how many bad ones I have dealt with.  What usually happens when you get a bad fuel pump is. You start it up and it runs for about 20 minutes then starves out and dies.  You try to restart and it won't, then you prime it and the issue starts over.  

 
Can't tell you how many bad ones I have dealt with.  What usually happens when you get a bad fuel pump is. You start it up and it runs for about 20 minutes then starves out and dies.  You try to restart and it won't, then you prime it and the issue starts over.  
Huh.  Must be a Zonie thing. :biggrin:

Either way, he shouldn't have to prime for a huge amount of time, but the button is there for a reason.

 
Huh.  Must be a Zonie thing. :biggrin:

Either way, he shouldn't have to prime for a huge amount of time, but the button is there for a reason.
He was thinking of draining the tank by using the prime button is how I read it. 

 
Whatever you do it’d be a good idea to go purchase a backup carburetor, they’re around $100. 

 
He was thinking of draining the tank by using the prime button is how I read it. 
Derp.  Yeah, that's a bad idea.  Prime the siphon?  Sure.  Running for 20 gallons straight?  I mean, it'll do it...

 
He was thinking of draining the tank by using the prime button is how I read it. 
Then I'd be blowiing up the pump on the gen for sure.  Gonna use the fuel station to empty the gas that is in the tank.  Then do start the process.

 
If you feel you need to pull fuel through the lines without using the priming system why not just get one of those $5 siphon ball/pumps at the parts store? Put it on the end of the fuel line before you connect and draw fuel through the line until the air is out. Then you only have to prime the last little bit to the fuel bowl. 

 
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