'67 110 9.8 hp Merc - prob.

[LaTechSlack]

I have the above ref'd outboard. The motor is in mint condition (i.e., looks like it has NEVER been run); I acquired it a few months ago . I tried to use it for the first time this past weekend. It started on the first couple of pulls and ran great for the time I used it (operation time about 20 min). When I tried it in the afternoon, I noticed it would not run on the "top-end" when at full throttle (i.e., only ran at around 1/3 to 1/2 hp) and had trouble starting (e.g., would "sputter-out" when put in gear). I looked at the plugs, and they were fine. I put my other motor to use ('67 Evinrude - 9.8 hp), as a spare, for the time being, but noticed it was operating EXACTLY like the Merc. I decided that maybe it was more than a coincidence and looked at the gas. The gas was, I believe, three to five months old, but had a fuel stab. in it. The gas smelled like "laquer" to me w/ a "yellowish" tint. I'm thinking that it is not just a coincidence and that it is a "gas-gone-bad or bad-gas" problem that has resulted in "clogging" the "high-end" carb ports. Is there anything I can add to a fresh tank of gas that may aid in "cleaning-out" the carbs on both of these motors, without breaking the carbs down? I've heard that NAPA has a product called SEAFOAM that you can add to your gas that aids in cleaning. What about "spraying" a product in the carb itself to maybe aid in it's cleaning. This may not be my problem but I sure would like some direction. FYI, the fuel I run is high-octane/premium w/ 50:1 ratio. Hope for some help. Thanks. <br /><br />Michael

 

[mred 2436]

Re: '67 110 9.8 hp Merc - prob.

michael : yes it seems you have bad gas although it may be that you have used a cheap two cycle mix. three to five months of sitting will cause even high octane fuel to go bad, especially if it sat in the sun or a heated room. however, it should not have gone far enuff to get any real amount of "gum" build up. i would try disposing of the old fuel, and starting with a fresh mix. when you run your engine, just set and let it run at moderate throttle for a few minutes to cycle the new fuel thru your system.