9.9 hp sailmaster

[bob brousseau]

I purchased a catalina 25 which came with a 9.9 hp johnson sailmaster. The original owner told me although he lost the manual it said to only use a mix of 100/1 oil mix, everyone I know who owns an outboard motor says use only 50/1 mix. Can anyone help?Thanks Bob.

 

[Tim Salkeld]

100:1

100:1 will be fine for an older sailmaster. 50:1 will foul the plugs faster. Make sure you shake the fuel up before using if it has sat for a while so as not to go below 100:1 and use a fuel stabilizerTim

 

[john renfro]

smoke

hello bob, the manual for my old 70 hp mecury outboard recommends 18:1 ratio.older engins needed more oil. if the manufacturer recommends 100:1 ,rest assured 100:1 will work well. more oil will cut the power output, foul the plugs, get oil on your hull,leave an oil slick on the water, be harder to start, and smoke. john

 

[Randy]

Some were 100:1

I worked for a fellow about 15 years ago who had rental boats with 6hp Johnson engines. There was a sticker right on the engine indicating 100:1 gas to oil. We ran them at 50:1, because our pre-mixed fuel sold at the pump was 50:1 to satisfy the tremendous majority of customers at the fuel dock. Given that they were used as rentals, I don't think the extra oil was a problem, and maybe even contributed to longer engine life.Randy

 

[dave holtgrave]

100/1

use the 100/1 i have the same engine and if you use 50/1 it will foul the plugs within 6 hours

 

[bob brousseau]

100/1 thanks guys

Thanks guys, looks like 100/1 is the way to go. Thanks again.