Boat won’t stay running

Hello all!
So I posted on here a few weeks ago and about my issue but I was hoping to post again to see if I can get more help.
So the problem I have is that when the boat is warm or has been staying in the sun it does not want to remain running. If you prime the carburetor with the throttle it starts up just fine but after that it will not remain running. If you open the engine housing and try to start it, there is no issue and it runs perfectly. The second you close the housing it seems as if the motor is choking itself and does not have efficient clean airflow. I have cleaned the flame arrestor and all the tubes and lines going to the carburetor that I can, with no luck. The same problem still exists. I was curious if anyone could give me suggestions and to what they think it could be.

Thank you in advance
Jon

So that was one of the suggestions that a few other ski nautique owners have suggested. I am unable to determine if that is the case. It was hard to locate a leak if there is one at all out on the water. So we tried running it in the driveway and we could not find one.

I just got off the phone with a guy and we are wondering if there is a leak coming from my oil vent which is where the hose from the flame arrestor is coming from. We have a few ideas of how to determine if that is it. Probably going to see if that is the case tonight

The more I think about it I am incorrect saying it didnt go away while we were moving forward. It was when idling and going slow that caused the misfires. When we would lift the motor cover it ran fine. Now I recall from 35 years ago, before we fixed the muffler we propped the motor box open with beer cans and we could continue on our slow midnight cruise. Oh those were the days! 18 years old and not a care in the world.
Hope you find the issue.

heh...

Woody Harrelson and Marisa Tomei Sing “Those Were The Days”
https://www.youtube.com/watch?v=WDixKh3Zhu0