2001 Yamaha 130hp 2-stroke woes

[Scout Sport Fish]

Ok, started it up for the new season and it ran perfect. Didnt even change the spark plugs yet.

Brought it down to the marina, dropped it in the water, started her up, and she would not stay running. No big deal I though, ran it with the choke on thinking some water was in the gas. Still wouldnt work. When I turn the choke off, it runs a little choppy at 400-500 RPM. With the choke on, same RPM range, just strong. Simple fixes, I did new spark plugs and a new fuel water separator. Then, it still would do the same thing. Now Im thinking it isnt running on all 4 cylinders. I check the wires and they are flowing current and I know its not the spark plugs as the engine was doing it BEFORE and AFTER they change. I have a feeling it might be the top port cylinder as it was cool to the touch as opposed to top starboard. Thought maybe my new filter was to restrictive at 20 microns so I just did a straight run from the fuel tank to the engine. Im going to try a compression test tomorrow to see if its a head or cylinder gasket possibly. Any input would be GREATLY appreciated.

 

[Scout Sport Fish]

Re: 2001 Yamaha 130hp 2-stroke woes

Thinking more and more about, it could be the carbs. If the fuel isnt getting into the top port cylinder, obviously I wont get combustion and the block would be cold.

Ill pick up new gaskets and rubbers tomorrow.

 

[cousinabe]

Re: 2001 Yamaha 130hp 2-stroke woes

Yep, sounds like trash in your carbs. Also, use a 10 micron filter.
Post the full model number.

 

[Scout Sport Fish]

Re: 2001 Yamaha 130hp 2-stroke woes

Looking at my filter, it says 10 microns, must have grabbed the wrong one off the self. Even then, I bypassed the filter/seperator thinking that could have been the cause.

This raises my other question. Beside a fuel water seperator, does it also filter my fuel? The previous owner had the brilliant idea of using glue to seal the onboard Yamaha fuel filter cap on. Cant get it off and the plastic housing is to flimsy to use a vise grip or somthing.

 

[Scout Sport Fish]

Re: 2001 Yamaha 130hp 2-stroke woes

Update:

I pulled the carbs out and took off the bowls. All sorts of varnish and gum in it. Got new gaskets between the carb and intake, assembled it all together again.

Now it runs, starts to bog down, hold the choke in, runs ok, then starts to bog down again because its on choke, turn the choke off, runs fine, then starts to bog down again and we complete the circle. Im at a loss, thinking about just bringing it to my local marina. =\