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2011 Yamaha 4hp 4 stroke won't start or fire

FishyBC

Contributing Member
A friend purchased this and it is in like new condition.
He took the carb off, cleaned it thoroughly but it does not fire. We put a spark tester on it and there is a good strong spark. We tried different positions for the emergency shutoff switch on the front but my understanding is that there would be no spark if that is not working correctly.
We also tried disconnecting what we believe to be the disconnect switch but it still has spark but doesn't even sputter.
I tried carb cleaner and it still did nothing.
My guess is it has to do with the shutoff switch but is there a fuse or something I'm missing ?
 
The kill switch/cutoff switch applies a ground to stop the motor from running. It disables the ignition. In which case there will be no spark.

While cranking the motor mist some gasoline into the air intake system. If it fires then you will know that it is a fuel related problem.
 
The kill switch/cutoff switch applies a ground to stop the motor from running. It disables the ignition. In which case there will be no spark.

While cranking the motor mist some gasoline into the air intake system. If it fires then you will know that it is a fuel related problem.

We still saw spark so it likely isn't the kill switch. I mentioned carb cleaner. I was spraying it into the carb. I don't expect it to run but I do expect it to sputter with carb cleaner at least for a moment but it does nothing. We'll try a replacement spark plug and if that doesn't work, I don't know what to try next.
 
While cranking the motor mist some gasoline into the air intake system. If it fires then you will know that it is a fuel related problem.

Just wondering what would be an easy way to "mist" gasoline into the intake? Plastic spray bottles tend to melt with gasoline, so what's the best way to do it? Thanks.
 
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