Sounds like a sucking noise....

[Tacklebuster]

Motor is an 05 150 Yamaha 4 stroke.<br />Today I put the boat on the water and ran it around to make sure my dual water/fuel seperators and such were in order. After dropping a few lines in for some trout, I noticed about 2 ounces of orange jelly stuff in the bottom of the bowl in one of the filters. I drained it out along with the rest of the fuel in the bowl. I then fired up my big motor and started to go. I heard a sound like the sucking sound of air or something. I gave it some throttle, the motor was a bit sluggish and then I felt a surge and all was fine. I then looked back and the bowl of the water/fuel seperator was full again. The sucking noise was still there but not as loud. It got faint yet but I can still hear it when the motor is turing 5400 to 6000 RPM's. The motor runs fine, smooth with no hick ups but I can still hear the faint sound.<br /><br />Any suggestion?

 

[WillyBWright]

Re: Sounds like a sucking noise....

It's probably your EFI system struggling with contaminated fuel. You're going to have to get that stuff out of the tank(s). What you're hearing is the idle air control valve in a very open position trying to maintiain RPMs.

 

[Tacklebuster]

Re: Sounds like a sucking noise....

I took my boat out today. I ran 13 gallons of fuel through the filter and the end result was nothing in the bottom of the bowl but gas. The sucking noise was gone as well. Best I can figure is the orange stuff was some kind of oil in the filter or something that was flushed out as soon as some gas ran through the filter?