F-Ribs And Sibs - Inflatable Boat Community

Just to be sure..I have a 6hp 2 stroke outboard motor on my 10.5 sib with a wood floor accessory, I'd like to know (with my 3 gallon external tank) how much gas would I need to spend say 8 hours fishing and exploring. I ask because I found out that I have to empty the leftover gas in a county landfill tank. I don't want to store the excess in my car(that's the only place I can keep it)because of fumes and it may be against the local law. If I get an idea how much I would use in a day on the water I won't have to waste too much gas by dumping it.

Robert,

My solution to that is to simply use the funnel that came with your vehicle and pour it into your car fuel tank. The minimal amount of oil in the gallon or so of marine fuel is nothing when diluted by the10 gallons in your vehicle tank. Rather than pour the fuel into the vehicle, I just use a cheap battery-operated hand fuel pump to pump it into the vehicle. Just remember it is always better to waste a little fuel than risk your life by running out on the water.

I would say you want the 3 gallon tank full for 8 hours on the water. There is only one way to find out. That is take it out and see what you use.

A rule of thumb is 1/3rd of the fuel capacity to get you to your destination . A 1/3rd to get you back to port ( where you launched from) and a 1/3rd in reserve to potter about. As for how many litres per nautical mile varies with rpm/speed , load, balance and sea/lake state. The boat hull and size/pitch of prop will come into the equation. Also having fresh fuel with correct amount of 2 stroke oil mix makes a world of difference. Even a 4 stroke outboard engine improves consumption slightly when the oil and filter is changed.
As Gray has rightly mentioned taking the boat out and recording the progress is a sure way of calculating the consumption. But, you can carry a spare fuel gallon can just in case. Stay Safe