Power loss Yamaha vmax 200

[bman]

Had hoped to go fishing but the weather forecast killed that. So I spent part of the day cleaning the boat.
Took it out for a short test run in the channel yesterday. Everything is working well but when I came off of throttle from high-speed the boat lost power and shut off. It's a Yamaha Vmax 200. Motor cracked up again immediately and ran fine on the way in.

I've never had to prime the boat to crank it up. But when I lost power I noticed the primer bulb was not firm. Maybe an air bubble in the line because it's been sitting up?
Any ideas?

[tailwaters]

My motor did the same thing last year. At first I thought it was the low pressure fuel pump going bad but it ended up being something much easier to fix. One of the internal fuel filters wasn't screwed on properly which allowed air to get in the fuel system. This caused a lose of vacuum in the fuel system. I found it by taking the cowling off the motor and pumped the fuel bulb as hard as I could. This forced fuel out where the air was coming in thus identifying the source of the issue. Hope this helps.

[zload]

I would guess air getting in from somewhere