Yamaha 115 cutting out.

What would cause a motor to cut out at High rpms?5500…. good all the way up to about 5500 rpms. Spark plus new, Fuel filter new..fresh gas…im th im thinking fuel pump…

Does the 115 have the VST filters ? Otherwise injectors . My 150 had clogged injectors and VST screens . Would get to rpm’s and slowly go backwards .

We had a 115 Yammy that did similar.
LaCannes couldn’t figure it out
Yamaha rep either.
Mechanic came in early 1 day to work on it. Still dark out. Started the motor and turned the lights off. Sure as poop, could see sparks. A wire had shorted out. Replaced it, problem solved.

Might be worth a try.

We are having issues with one this weekend. Going to start with the simple stuff and Put new plugs in.

Had the same problem. Separated inner liner of fuel hose starved the engine at high rpm.

Change the fuel filter which to is on the motor. Very easy to do and costs about $25 – $30 .

welliou wrote:

Change the fuel filter which to is on the motor. Very easy to do and costs about $25 – $30 .

Done

spkwms wrote:

Had the same problem. Separated inner liner of fuel hose starved the engine at high rpm.

Changed all lines Monday except bulb. Store didn’t have where I bought the lines..

Yesterday on the water, It started to buck sou I gave the ball a squeeze…Helped…Did it again, squeezed and ran fine back to the landing doing this when it bucked……Bulb? or Fuel Pump?

There is a low pressure fuel pump right after the fuel filter that feeds the VST. Might be worth getting a replacement diaphragm for it or a new pump all together. Sounds like the fuel bulb might be the issue too. I would give Sheldon’s Auto & Marine Service a call and pick his brain.

Off to the mechanic to get this one fixed.

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Chappy, what year is your Yamaha?

115 Yamahaq 2010

Finally after talking to alot of mechanics I can no longer wait…Took her in to Redwing Powersports Sat. to be wored on next week. Sounds like the VST filter. Update next week.

It indeed was the VST and also had a restriction in the gas line. Got her back yesterday.

chappy wrote:

It indeed was the VST and also had a restriction in the gas line. Got her back yesterday.

Glad you got her going – do you have a water seperator filter ? I do not but have kicked around adding one . Very popular in the south . Seems crazy adding a 3rd filter before the injectors but clogged screens ain’t fun either

For a long time I really wanted fuel injected instead of carbs. Even though my f50 is old, it has that super nice filter built right into it. I don’t see how some $10 auto part store thing is going to be better.

Nope… not fixed yet and I think it may be worse now as it has developed a miss….so.. back to the shop..

So…. after the boat in the shop for a month, it turned out to be…..low pressure fuel pump…

So it was not the VST? They charged you for something that was OK?

Mike…What was wrong with your motor?