Yamaha F90 2014 engine dies

[bryanzzz]

Guys, motor runs fine until it acts like it ran out of fuel. This has happened several times, pump bulb and it fires. Today no luck, stranded for an hour, I bypassed the fuel water separator, running fuel line from tank to bulb, no luck, drained the vapor separator and it fired up and got me to ramp. My question is can a dealer hook up to and ID an electronic problem or fuel pump problem? My troubleshooting does not show a problem with fuel delivery to engine, my guess is motor issue....Thanks in advance for any help I can get...I changed the fuel water separator last month and today ran a hose from a 5 gallon tank straight to primer bulb, no difference.

 

[Capt Ken]

YDIS can check sensors but your problem is contaminated fuel and probably plugged the internal filters on the engine. Bet you have a plastic fuel tank and using ethanol fuel.

 

[bryanzzz]

Hey Capt'n let me a give a little more info. Boat and motor ordered in April 2014, six weeks took delivery, third trip to lake on same tank of fuel and I experienced the first episode, motor runs fine then dies. No other problem until this spring, several more episodes where engine dies and fires back up, after pumping bulb. The rest is history, see my original post. I use blue fuel stabil, store boat in basement, has plastic fuel tank like 99% of boats sold, buy a 50K pickup and it has a plastic tank. I'm a little stressed with my problem and spoke to a dealer today, will try portable tank and feed fuel straight to engine, probably buy a plastic tank. Open to any info from an experienced mechanic or boat owner, Thanks in advance.

 

[Propwash79]

I would check the thread for testing fuel problems.sounds like it's fuel related like a fuel pump because you can pine the bulb and your good to go.

 

[bryanzzz]

Bought a 3 gallon tank today, will run straight to primer bulb into engine, if it happens again I will put in shop, intermittent problems hard to ID. Thanks for input.

Problem has to be either fuel delivery or engine related. Motor under warranty but if dealer cant duplicate not sure how Yamaha will handle...Dealer has a lot of respect or Yamaha....we will see.

Motor/boat has less than 30 hrs.

 

[bryanzzz]

Dealer found the vent off the VST tank was crimped from the factory, causing vapor lock. Cold engine cranks fine, up to operating temp and shut down for 45 minutes and motor dies. Looks like all OK now.