Proper Oil mixture for a 95 Yamaha 2 stroke

[xpressflats]

Is it 50:1 or 100:1?

Also, would adding more oil cause it to run cooler or cause it to run lean and be hotter?

Thanks for looking! I am a brand new boat owner and are having some problems.

[strokersquid]

there is not much difference in the fuel: oil ratio in that range. that is you are not getting much more fuel by going to a 100:1 from a 50:1 oil ratio, less than 1% ( 1 oz per 138 oz gallon ). the concern here is lubrication. I'd er on the side of more oil myself.

[robert graham]

50:1(2.6 ounces/gallon) is the most used and widely accepted fuel/oil ratio for your motor. 100:1 is cutting it pretty thin from a lubrication standpoint, as well as an internal corrosion standpoint. When you turn your motor off for a few days, weeks or months that little bit of oil in the fuel mixture remains on the crankshaft, rod and piston bearings to help prevent corrosion. Good Luck!

[Ldavidgrover]

Depends on what motor you have. Stick with what is recommended.

[strokersquid]

My old Johnson Sailmaster stated a 100:1 ratio, but they did that only for a couple of years before going back to 50:1. Too many seizures. If you're off just a touch at 100:1 it may cause damage.

[fisherguy123]

I had a 1988 suzuki 30 hp......sticker on it said 100:1 fuel /oil ratio. I asked a dealer tech and he said do the 100 to 1 to a max of 90 to 1. It is the way the engineers designed it. Ran it full out for 8 seasons in salt water and it ran perfect when I sold it last year. The new owner mixed it 50:1 and said it idled like crap when trolling......i told him to go back to 100:1 and he said it smoothed right out and he ran it all the rest of last season without a hitch ! This motor was a gas guzzler as I realize now compared to my 1982 merc 50 so I suspect that the quantity of fuel going through it added to the lubrication and cooling of the motor and not so much oil is required.

[99yam40]

the only bad thing I have heard about running 100:1 on motors designed for that , is not much protection of the shiny internal parts while motor is not running, sitting for periods of time in the wrong environment and cause rust on bearings, shafts ,cylinders, etc.
Which is very bad and not many people run there motor every day or two to keep things lubed well