HELP...yamaha 150 looosing power

[minardo61]

I hope someone can help me here, I have a 2001 yamaha 150 the problem im having is after cruizing for about 1/4 mile at any speed the motor will loose power it never shuts down i usually put it in neutral then try to take off again it will start go get up then bogg down again. i have drained my fuel water seperator with very minimal water there is some minor debris but there is no debris in the filter in the motor i sprayed the carbs with cleaner during one of the times this has happened and there was no response the problem continued...im starting to think that i have an electrical scensor problem because if i shut the motor down and achor up for a while it will run fine for about another 1/4 then the problem will come back. does anyone have any tips i could really use them.

Thanks

 

[Marv]

Re: HELP...yamaha 150 looosing power

Check fuel line connectors for leaks/cracked seals. Drain carbs, see if your fuel tank is venting air in.

 

[minardo61]

Re: HELP...yamaha 150 looosing power

I have checked most of those things that you have listed i have not drained the carbs and i dont believe im drawing a suction when i filled my tank it over flowed out of the vent. i could try it again and when the problem occurs jus open the cap.. Any other ideas.

 

[rodbolt]

Re: HELP...yamaha 150 looosing power

in 01 there were at least 4 versions of the 150, all with different fuel and ign systems.
we need a model number to speak coherently.

 

[minardo61]

Re: HELP...yamaha 150 looosing power

well i finally got the model 150txry all other numbers were corroded off but i figured i would try to change the thermostats incase the engine was over heating and cuttin back what i found was two severly corroded thermostats one of which was falliing apart and i had to pick out most of the pieces and replace them and the gaskets i will be testing it this weekend and let you all know if that was the whole problem

 

[rodbolt]

Re: HELP...yamaha 150 looosing power

150TXRY,150,trim,25"shaft,remote control and 2000 year model run.
your describing either a bad lift pump or dirty carbs or both.
electricl problems are very rare with that engine.
you can test the sparkplug caps,the thermosensor and the crank position sensor however they rarely fail.
if it was an overheat you would get RPM reduction to 2500 RPM max and an audible alarm and a visual.
have you tested the audible alarm latly to see if the horn actually works ?
quick way on your model is simply pull the stop lanyard and crank the engine, if the system is working you get an audible.
spraying carb cleaner down the troats while its running is not only useless but rather harmful to the motor, see how polite I am today .
like I always say, test spark,test compression, go fix the fuel system.