Compressed air to start a siphon?

[The motor guy]

Ive seen it where people take an air nozzle and shove it into a hole they made in the side of a siphon hose. My question is how long of a hose will this work on? I want to get rid of some of the fuel out of the fuel tank on my boat and fill up some 5 gallon gas cans

 

[Sequoiasoon]

I'm not sure there is set number/distance limit. Using the compressed air with a notch like this I/ at the end, blowing away, is basically like you doing the old lips and sucking thing except you don't get the tasty fuel in your mouth thing.

 

[The motor guy]

I'm not sure there is set number/distance limit. Using the compressed air with a notch like this I/ at the end, blowing away, is basically like you doing the old lips and sucking thing except you don't get the tasty fuel in your mouth thing.

Except the air nozzle is non stop. My guess is it will flow as along as the vacuum continues. My plan is to connect fuel line to the fuel tank, then run it over the gunwale and down 7ft to gas cans on the ground and that should be enough of a drop to keep a gravity feed flowing without having to continue the air nozzle

 

[oldhp]

I've just shot air across the opening of the hose until fluid comes out, then put end of hose in bucket. It'll siphon until upper tank is empty.

 

[Lubener]

Ive seen it where people take an air nozzle and shove it into a hole they made in the side of a siphon hose. My question is how long of a hose will this work on? I want to get rid of some of the fuel out of the fuel tank on my boat and fill up some 5 gallon gas cans

Just go to Harbor Freight. For $7.99 you can buy a hand pump for fluid transfers.

 

[The_Jeff]

https://en.wikipedia.org/wiki/Venturi_effect

 

[Arc]

I just did the same thing on my radiator to purge all the antifreeze. A little pressure will push anything out.

 

[Gyro Gearloose]

Or if there is more gas in the tank than you care to pump you can use Lubener's pump at the lower end of the siphon line to just pull the vacuum to get the siphon started.

 

[BC1]

With 7 foot of head, just stick as much of the hose you can in the tank and then put your thumb over the end. Climb down and put the hose in the 5 gallon can.

 

[The motor guy]

Just go to Harbor Freight. For $7.99 you can buy a hand pump for fluid transfers.

The hose isn't long enough on those and im not going to be pumping it the whole time. I have plenty of 3/8" fuel line. Only issue is its not clear so I cant see whats going on.

 

[JWC86]

7ft will be plenty for this to work and keep going, I do it all the time with motorcycle tanks that are only a few feet off the ground.