converting a dual line pressure tank to single line?

[nwcove]

i can remember reading a post about converting a dual line pressure tank to single line ( just to keep the "look" of the old pressure tank). did some searching and cant seem to find the post. is it reasonably easy to do?
i have a "suitcase" tank that looks like it will clean up ok, or should i not modify it...maybe pass on to a good home?? ( the rochester guage looks sooo nice!! lol)

 

[64osby]

Re: converting a dual line pressure tank to single line?

Good one's around here go from $40 to as much as $120. They are getting harder to find.

I say pass it on or keep it for another project motor.

I have one tank that is styled like the old pressure tanks, but it is a single line feed. Solid cap over the big hole, no gauge.

 

[F_R]

Re: converting a dual line pressure tank to single line?

If your heart is set on a fuel pump system, a fuel pump can draw fuel out of the pressure tank. All you need to do is adapt the hose, and leave the cap loose for a vent.

 

[HighTrim]

Re: converting a dual line pressure tank to single line?

I did it for someone last summer. I simply did as Frank stated. I just blocked the pressure side of the hose and the seller drilled a hole in the cap. I wouldnt do it

I couldnt understand it, as buying a good single line tank is much less than a good pressure tank. But just my 2 cents.

 

[andrewcoon]

Re: converting a dual line pressure tank to single line?

HOW TO CONVERT 50s motors from two line tanks - YouTube Watch it!

 

[HighTrim]

Re: converting a dual line pressure tank to single line?

HOW TO CONVERT 50s motors from two line tanks - YouTube Watch it!

He is very aware how to convert a pressure system to fuel pump, he has done a few. He is referring to converting to a fuel pump while maintaining a pressure tank, for cosmetic appearances.

 

[nwcove]

Re: converting a dual line pressure tank to single line?

i think i'll leave the suitcase tank alone. i do have the qd-10, that the tank came with, might get adventurous someday, and try to fix the buggered up ( complicated looking) linkage set up.

.....not sure where i got that pic, but its not my motor or tank. lol

 

[kbait]

Re: converting a dual line pressure tank to single line?

If I remember correctly, with a 'pressure fuel tank' the fuel can be 'pushed' out from the screened tube that is fed from the bottom of fuel tank, but you can't 'suck' the fuel through, as in a fuel pump system. I'm pretty sure there's a one-way valve in there somewhere, which would need to be disabled to use old school tank w/fuel pump setup.

Good luck!

 

[F_R]

Re: converting a dual line pressure tank to single line?

Actually, there are two check valves (#35), but there is nothing holding them shut except gravity, and they weigh next to nothing. In other words, not to worry, they will lift by suction just as easy a they will be pushed by pressure. In reality, it is all the same thing anyway.

 

[kbait]

Re: converting a dual line pressure tank to single line?

FR is right. You just can't push fuel back into tank, but pushed or 'sucked' out of tank is all the same w/valves. Now I know too!

 

[HighTrim]

Re: converting a dual line pressure tank to single line?

yeah as frank stated, I did not have to remove the check valves and all worked well.

 

[Crosbyman]

Re: converting a dual line pressure tank to single line?

if a pump is installed and the pressure side of the dual line is left open "to air" at the dual line motor connector, would that not allow for air to be sucked in the tank while the equivalent fuel volume was being sucked up to the engine by the pump ?.... it would become unnecessary to drill a hole in the tank cap since air would come into the tank via the hose "air side" . presumably the 2 check valves wont mind .

 

[F_R]

Re: converting a dual line pressure tank to single line?

if a pump is installed and the pressure side of the dual line is left open "to air" at the dual line motor connector, would that not allow for air to be sucked in the tank while the equivalent fuel volume was being sucked up to the engine by the pump ?.... it would become unnecessary to drill a hole in the tank cap since air would come into the tank via the hose "air side" . presumably the 2 check valves wont mind .

Crosby, your thinking is correct. In any case, drilling a hole is completely unnecessary. All one has to do is crack the cap open a bit and it will get plenty of air.

 

[andrewcoon]

Re: converting a dual line pressure tank to single line?

Since a single line gas tank needs a vent I think you would be fine just using one hose (gas) with the pressure tank. And maybe from some sort of plug so you can close the air when priming the engine

 

[F_R]

Re: converting a dual line pressure tank to single line?

Since a single line gas tank needs a vent I think you would be fine just using one hose (gas) with the pressure tank. And maybe from some sort of plug so you can close the air when priming the engine

Contrary to popular belief, pushing the primer does not pressurize the tank. So no need to seal it up for priming.

 

[F_R]

Re: converting a dual line pressure tank to single line?

Since a single line gas tank needs a vent I think you would be fine just using one hose (gas) with the pressure tank. And maybe from some sort of plug so you can close the air when priming the engine

Contrary to popular belief, pushing the primer does not pressurize the tank. So no need to seal it up for priming.

Operating the primer button pumps gas to the carburetor so you can start the motor. Once running, the motor pumps air to the tank to pressurize it so it keeps running.

 

[bbryant0384]

Re: converting a dual line pressure tank to single line?

Does anyone know if there is a newer model tank that I can purchase to swap out the old Johnson 2 line pressure tank that I have and use it instead. Like perhaps a plastic tank. I don't necessarily need to change from a 2 line to a one line like I have read some people doing, I just want to find something more accessible and modern if possible. I am new to this so sorry if it sounds weird or doesn't fully make sense. Thanks.

 

[HighTrim]

Re: converting a dual line pressure tank to single line?

You can use a single line plastic tank bryan, but you also need to install a fuel pump. The pressure tanks acts as a fuel pump, so if you remove it, without installing a pump, fuel will not be able to get to the motor.