Have Boat Questions? Ask a Boat Repair Expert.
Hello. My name is Tan.
The engine is starving for fuel. Run the engine on a different fuel source. Does it run better?
Disconnect the fuel supply line going to the engine. Plug the fuel line. Now get some fuel hose and a gas can. Connect the fuel hose to the engine and stick the other end of hose in the gas can. Secure the gas can go run the boat. Does it run better or the same?
This is a process of elimination. Your symptoms are of fuel starvation. So I start at the fuel source and work my way towards the engine. When we eliminate the boat side fuel system it will tells us if we have an engine issue or a fuel delivery problem.
This is the simplest and easiest test that can be done with minimal trouble shooting tools and skills.
The most likely issue here is debris in the fuel tank pick up tube clogging or restricting the anti siphon valve.