Gas usage formula

[nimmor]

I am looking for a formula to figure gas usage of my 9.9 Johnson. I have a 6 gallon tank but am considering switching to a 3 gallon tank to reduce weight and space, but mostly to keep from having extra gas sitting around between outings and going stale. I don't know if it makes a differance but the motor is a 1989 on a 15 ft v-hul.

 

[dingbat]

Re: Gas usage formula

Generally speaking outboards will use 10% of their rated horsepower per hour at WOT. Your 9.9 Hp will use roughly 1 gallon per hour at WOT

 

[bassboy1]

Re: Gas usage formula

dingbat is right on the usage. Just out of curiosity, is your hull aluminum or fiberglass, and how fast does that lil' motor push you?

 

[nimmor]

Re: Gas usage formula

The hull is aluminum. I could go with a bigger motor on this boat but I have several 10 horse or less lakes around here that I fish on and it doesn't move the boat too bad.