2001 Yamaha 50 H.P. 4-stroke fuel advice

[Makky]

I just had my four carbs overhauled by a marine mechanic and he gave me the usual advice about E-10 and the importance of chemicals in the gas. He advised using nonoxygenated fuel as well. I am all set to do this when I
was told that the Yamaha people do not advise this because of the 92 octane. I guess this engine is not designed
to burn the hotter fuel without causing some engine problems. I would be interested in hearing what other marine
mechanics have to say on this subject. Thanks for any help.

Makky

 

[Silvertip]

Re: 2001 Yamaha 50 H.P. 4-stroke fuel advice

92 octane fuel is not hotter fuel. It has a slower burn rate than regular fuel to retard detonation. The higher an engines compression ratio is, the greater the tendency to detonate and therefore the need for higher octane. Your engine does not have high compression nor does it need anything other regular grade fuel (E-10 or standard). Using higher octane fuel does not increase power on engines where higher octane is not required. You were given incorrect information or misunderstood what you were told.

 

[mommicked]

Re: 2001 Yamaha 50 H.P. 4-stroke fuel advice

Ive been told by several folks,including the previous owner of my 03 F90 to use Yamaha Ringfree additive in my gas w every fill up as it will prolong the life of the engine.But Im no expert.I do use it.

 

[Silvertip]

Re: 2001 Yamaha 50 H.P. 4-stroke fuel advice

Ive been told by several folks,including the previous owner of my 03 F90 to use Yamaha Ringfree additive in my gas w every fill up as it will prolong the life of the engine.But Im no expert.I do use it.

Sticking rings and the resultant loss of compression is nowhere near the problem on a four stroke than it is on a two stroke so I question the usefulness of that particular additive -- but it won't hurt anything except your wallet.

 

[Makky]

Re: 2001 Yamaha 50 H.P. 4-stroke fuel advice

Thanks Silvertip for the fuel advice. That makes sense. I still would like to get away from the e-10 by going to the nonogenated type fuel. As I understand it, the higher octane would not hurt the engine?
Thanks for your help.
Makky

 

[robert graham]

Re: 2001 Yamaha 50 H.P. 4-stroke fuel advice

Just run any 87 octane pump gas, with or without the 10% ethanol. Use the Stabilizer like Stabil or Seafoam to help prevent fuel from growing stale or degrading during long periods of time in the tank. Install a fuel/water separator type filter on your boat. Good Luck!

 

[jeffersondodson561]

Re: 2001 Yamaha 50 H.P. 4-stroke fuel advice

Ringfree is some amazing stuff, I have seen large pieces of carbon come out of the exhaust on older two strokes good stuff same as quickleen but not good enough to run a constant mix, works as good or little better than BRP Engine Tuner easier to use harder on the wallet...my question: Is sea foam a fuel stabilzer or a decarboner?

 

[Silvertip]

Re: 2001 Yamaha 50 H.P. 4-stroke fuel advice

Ringfree is some amazing stuff, I have seen large pieces of carbon come out of the exhaust on older two strokes good stuff same as quickleen but not good enough to run a constant mix, works as good or little better than BRP Engine Tuner easier to use harder on the wallet...my question: Is sea foam a fuel stabilzer or a decarboner?

It is both. Depends on how you use it. Heavily concentrated it is a great decarbonizer. As a fuel additive it is a great fuel conditioner.