Yamaha won't run long

[Dom#1]

I have a 1984 30ELN Yamaha. It starts but won't run long when I run it with the muffs. Last year when I loaned the boat to a friend he had similar problems and the guys with him were all "mechanics". They pulled the carb and the fuel pump. He replace the pump but I think it was a used one, don't know if it's any good. I installed a carb kit and replace the hoses under the cover after that but when I pump the bulb gas does leak at the connection at the motor. What do yall think could be the problem? Is it sucking air at the connection at the motor or could the pump be bad or what else?

[99yam40]

If fuel leaks out, then air can get sucked in. Sounds like you need to replace some connectors or o-rings if you can find them.

Use a fuel pressure/vacuum gauge to test the fuel pump inlet and outlet.