Octane level?
I realize the oil fuel mixture was changed back to 50:1 from the 100:1.
Further to that the full range of recommend Octane is from 86 to 91 for my motor.
When I bought my motor back in 1986 ethanol in fuel was not*part of the picture.
In my area it*now makes*up 10% of volume.
My question is with todays blended fuel which*octane is best or does it not matter?
I never gave much thought to Octane always opting for 86 because of cost then a light went off making me consider Octane and the effects of methanol on older 2 stroke outboards. Any thoughts?
Oil / Fuel Mixture
I have*found a oil/fuel mixture after years of experimenting which works best to be 75:1 for trolling.
In fact I now have two tanks in use which I mix one 75:1 for trolling and one 50:1 for high speed running.
A 11 liter tank for trolling and 22 liter tank for high speed.
Tend to run on remote lakes which requires the availability of extra fuel any ways.
This combination tends to get me thru a weekend without having to refuel.
I found this combination reduces fouling and extends plug life and run time before having to change or clean them.
In fact I have found I only need to change them at a proper interval ( yearly ) never have to clean them.
Plus I find I can get lower trolling speeds when needed.
From my research on the 100:1 issue I determined rightly or wrongly it was more of an issue with the bigger horsepowers where the problem was more an issue with mixture errors ( human and mechanical).
I realize the oil fuel mixture was changed back to 50:1 from the 100:1.
Further to that the full range of recommend Octane is from 86 to 91 for my motor.
When I bought my motor back in 1986 ethanol in fuel was not*part of the picture.
In my area it*now makes*up 10% of volume.
My question is with todays blended fuel which*octane is best or does it not matter?
I never gave much thought to Octane always opting for 86 because of cost then a light went off making me consider Octane and the effects of methanol on older 2 stroke outboards. Any thoughts?
Oil / Fuel Mixture
I have*found a oil/fuel mixture after years of experimenting which works best to be 75:1 for trolling.
In fact I now have two tanks in use which I mix one 75:1 for trolling and one 50:1 for high speed running.
A 11 liter tank for trolling and 22 liter tank for high speed.
Tend to run on remote lakes which requires the availability of extra fuel any ways.
This combination tends to get me thru a weekend without having to refuel.
I found this combination reduces fouling and extends plug life and run time before having to change or clean them.
In fact I have found I only need to change them at a proper interval ( yearly ) never have to clean them.
Plus I find I can get lower trolling speeds when needed.
From my research on the 100:1 issue I determined rightly or wrongly it was more of an issue with the bigger horsepowers where the problem was more an issue with mixture errors ( human and mechanical).
Last edited: