HOW TO SIPHON LIQUIDS
The proper way to get a good flow when you need it.
Boaters may run into the need to siphon fuel, water or another liquid. Whether you’re removing 65 gallons of suspect gas from a used-boat purchase (like I had to), or emptying a livewell or fish box when a pump breaks, siphoning is quick, easy and relatively safe. You can siphon just about any liquid, but it’s most common with combustibles because siphoning is safer and less expensive than pumping. —Craig Kotilinek
MAKE A PLAN Siphoning only works when the liquid to be removed is above the destination. The hose can go uphill for a bit, but its final destination needs to be downhill. For example, if your boat is on a trailer, you can set a gas can on the gunwale and flow into your main tank, but you can’t set that can on the ground and expect it to flow upward. Siphoning relies on gravity.
DON’T SUCK Don’t try to suck gasoline through a siphon hose. Instead, use one large hose going from the gas can to the gas tank and a smaller hose stuffed in alongside it. Wrap a rag around the two hoses to make a tight seal, then blow into the smaller hose. The pressure change will force gas from the can into the bigger hose and into the gas tank. This works best when the can is full.
MONITOR YOUR
PROGRESS The siphon will continue until the hose is removed from the liquid or the liquid is removed from the hose, so try to get the hose as far to the bottom of the can as possible. Try to keep the hose end at an angle toward the back of the can while you tilt the can backward and you should get just about everything. There are many methods to siphoning, but this is the one I’ve found to be the fastest with almost no spills. OTHER USES If you need to empty your main tank, first remove your positive battery lead as well as any source of spark, then remove your fuel line at the water separator and reroute it through the bilge into a separate container that’s meant to hold petroleum products. Then take an air compressor and blow air in through the tank’s vent hose. Your local dump may take the old fuel free of charge as a hazardous material, or you might have to pay a professional to transport it. Or run it through an old lawn mower.