I have a 2003 Nitro 288 Sport with a Merc 150 XR6. My issue is it takes a very long time to start the engine after it has sat for more than a few days. I pump the bulb and prime the engine prior to starting, always. The cranking battery is new. The spark plugs are new. I'm always able to get it started but it just seems to take a very long time. It "feels" like when the engine eventually fires and only runs for as long as the "primed" gas is in the system then quits. Then I prime again and it fires, and dies. Eventually it will fire and continue running. My assumption is that it takes that long for the engine to build the proper vacuum to pull the gas from the tank and run from that fuel source. But I'm no expert, just speculating. Any ideas? Thanks in advance.