04 Yamaha 115 fourstroke trouble starting

[Jhwaco]

I recently purchased a boat with Yamaha 115 four stroke. The last two weekends I’ve had on the water it has same issue starting. Starts right up when I put in the boat one the water. I can run around with no issues lots of power. If I pull up somewhere and shut off the engine sometimes I have issue with it cranking back up. Yesterday I cranked and cranked. Finally gave some throttle and every time I let go of key after cranking seem like I could hear it cough back like it was flooded and igniting fuel like a carb flooded on old car. After a few mins I finally got it started. Once the engine is running no problems. Any ideas

 

[rejesterd]

Sounds like too much fuel vapor getting routed back in through the air intake (which can flood the engine). There's a relief valve on top of the vapor separator that controls how much vapor will get sent. I would remove the valve and try cleaning it, since it's over $100 to replace.