Tracy,
To demo this to yourself, get a see through milk jug, fill it with water, use some air line to act like the fuel line, and start a syphon while the milk jug is above the simulated engine level. Water will flow to the simulated engine until you brake the syphon. Now try the same experiment with the milk jug below the simulated engine's height, the water will flow back into the milk jug and fail to feed the engine. Further, the bulb is there to "force" the fuel to the engine on a boat, then its fuel pump does the rest of the work pulling the fuel thereafter.
Does this help?
What he said. The bulb is to prime the fuel system. I think the siphon will work, but I have not ever done it myself. I see where it might seem as though it would not pull it from the top. As said earlier you might have to get a small fuel pump.
Got an idea, this is a bottom feeding portable fuel tank. It is 15 gallons. That would run for a LONG time. It is steel. You could adapt from the 3/4" to 1/4" or whatever is on your engine with brass fittings. With the bottom feeding tank, you can put it on a table of some kind, use gravity feed, have it a safe distance away for filling, and not worry about a fuel pump. It is kind of pricey but, after the purchase of it, a few brass fittings and fuel line you would be done. I bet 15 gal could run for 24 or more hours easy.
fuel tank Just another thought.
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