115HP Cough/Sneeze

[ncreappraiser]

I have a 2002 115 2 storke Yamaha and was on the water yesterday and it was running fine. I was running at WOT and slowed so I could position the boat to anchor. I noticed that when I dropped to idle the motor started skipping and sneezing and when I throttle up it bogs and may or may not eventually take the gas. I've had this boat a little over a month and have used it every weekend with no problems at all and now this. When hooked to the hose it seems to idle fine and then sneezes. Somone in the campground said it sounded like a broken reed. Since my tools are at home I can't check compression but does this sound right.

 

[erniefish]

Re: 115HP Cough/Sneeze

i doubt you cracked a reed, more likely your carbs are fouled,sneezing usually indicates a lean comdition,clean carbs

 

[ncreappraiser]

Re: 115HP Cough/Sneeze

Thanks for the reply. I did check the compression and all cylinders were 125-130PSI just to be on the safe side. Someone at the beach mentioned water in the fuel. The boat has a water separator but they told me if I had an excessive amount of water the filter would allow water through. This seems to make sense because another boater had the same problem yesterday and after talking to them I found they purchased their fuel at the same place I did. He changed his filter, which was full of water, drained his carbs and it ran better so he added something to the fuel to help with the water. I'm going to look into this today and see what my filter looks like.

 

[Doh]

Re: 115HP Cough/Sneeze

Idle Air jet.

Little brass screws, on each carb, at the back of each carb at the 10:30R/2:30L area.

Now rember these are Air Jets, so you have to turn them in, to enrichen the mixture. about a 1/4 turn each should do great.

 

[ncreappraiser]

Re: 115HP Cough/Sneeze

I pulled the separator off and there was some water but not as much as I would have thought. I tried the little brass screws but it did not affect the cough/sneeze at all. I also checked the fuel filter which was clean.
The thing that I can't figure out is that it was running perfect until I throttled back. I previously had an Evinrude that did the cough/sneeze thing but the throttle response was still good.

 

[douglloyd]

Re: 115HP Cough/Sneeze

Please do a search on this. You will find the answer.