Premium gasoline in out boards

[Norco]

Is it better to run premium gas in an outboard rather then regular??Or is a bad thing to do??

[Norco]

My motor is a 91 25hp Merc, I have noticed since trying a premium gas it's harder to start so I think Im going to switch to regular. Thanks for the info

[Gissert]

It is a widely held belief that higher octane equals higher performance. All octane is is a measure of resistance to detonation. The higher the octane number, the greater the detonation resistance.

I saw a poor soul a few winters ago fill his sled with 100 lowlead, avaition gasoline. He was fouling plugs left and right because his stock engine had not nearly enough compression to get the fuel to ignite properly.

[united jigsticker]

Hi Norco,

Is it a newer outboard?

If you have your owners manual, check the recomendation by the manufacturer.

My outboard is a 2002 and 87-89 octane is recomended.

Remember, the higher the octane, the MORE firing power it takes to ignite the fuel.

Good luck and good fishing.

[WaveWacker]

I run a newer 75 4 stroke and was told by the mechanic that if at all possible to run non-ethenol gas in it and every time I fill up with gas to throw in a can of sea-foam. I have a 32 gal. tank. He said that in the larger gas tanks, gas tends to sit around in them more before it is used and ethenol gas will start to "break down". Can't say that I have had any problems at all. My dad runs the same thing in his 6 gal tank for his 86 35hp more and that runs like a champ.