what octane

albass

Petty Officer 2nd Class
Joined
Jun 30, 2004
Messages
156
What octane gas should I be running in a 1991 Johnson Faststrike 150 ?
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: what octane

87 octane unleaded regular, twitch. Alcohol-free if you can get it.<br /><br />Good luck. :)
 

js361

Seaman
Joined
Apr 17, 2005
Messages
56
Re: what octane

I recommend higher octane 91+ (tip: Holiday gas stations have 93)....it's cleaner & burns more efficiently.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: what octane

Actually with todays fuel in a stock recreational outboard the higher octane will not burn cleaner. It also raises combustion temps compared to 87 octane. The 60 degree motors are kinda sensative to combustion temps. Too much octane combined with anything else that promotes excess combustion temps (lugging, wrong spark plug. timing, cooling system issues etc) can sometimes prove fatal.
 

walleyehed

Admiral
Joined
Jun 29, 2003
Messages
6,767
Re: what octane

93 flat killed our 175 Looper last summer, and after opening my eyes to the octane game and looking at the problems we have with radials running 100 octane in an engine designed for 80/87, I now realize the damage that can occure with high-test fuels..<br />As Dhadley said, 91-93 oct. is not needed or recommended but in a few High compression outboards, otherwise you're just waisting money and not doing your engine any justice...87 fits the bill, both the wallet and engine demand.
 
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