1996 Suzuki dt 40 not running correct

[Propwash79]

I bought the boat about 3 months ago and took it out 4 times and ran good each time. Before taking it out the 1st time I replaced the water pump,foot oil and the spark plugs are good. The boat sat for 3 weeks so I drained all the gas and fresh 93 with startron fuel treatment. It will run great on the hose but on the water it will run for about 3-4minutes then start to sputter for a few seconds and die to a idle then stall. The vent is open on the tank,fuel prime build still Good and round and no alarm. Went home and found no thermotastat in the motor. Installed new factory thermostat and still running bad. Even on the water I removed the thermostat and still no change except more water coming out of the exhaust hole when idling.Found crack on the fuel tank so replaced tank and fuel hose and still running the same. While on the water I could pull the choke and it would clear up a little and even squeeze the prime bulb and that would help a little. The motor will idle all day and run good at 1/4 through 3/4throttle but at full throttle or a little less it starts to drop off till it shuts off. Spoke to a outboard mechanic and he said it sounds like the fuel pump. I did read the thread about testing the fuel system but I'm not keen on throwing parts at it hoping it will fix it and really don't want tap out yet,any help is well appreciated
Thanks Steven

 

[Propwash79]

Went to the suzuki dealer today and picked up a fuel pump rebuild kit to be safe. Replaced the parts to the fuel pump and found the thin metal reed valves weren't seating correctly on the old parts..... Installed the new parts and all seems good. Going to take it out after work and see what she does.... I sure hope this solves the issue but I don't feel 100% and nothing stood out that was a failure.

 

[99yam40]

If you read the post on testing fuel system, why did you not test it?

 

[Propwash79]

Honestly it was cheaper and what the dealer and mechanic said would likely be.
****update,rebuilt the fuel pump and took it out today and it runs like a champ, only issue was let it idle for 2 min after running full throttle and it shut down. Wouldn't start so the wife and me had a romantic slow trolling motor ride. Half way to the dock and it started again. Let it idle back to the ramp and it shut off again. Prime bulb wasn't hard and could get 2 pump before it was hard. Shut off the motor and primed again and 15 seconds later the bulb was soft and took 2 pumps to get hard.... Ahh it's the carb needle valve not seating fully and leaking back. Off to he dealer and $23.65 for a rebuild kit. Will update once it's done. Next time out I won't go that far away to be safe.

 

[Propwash79]

***update. Rebuilt the carb and found the needle had a groove it it and the bowl was clean. Took it out about 1hr ago and it runs like a champ and will idle all day long and full throttle is awesome. It doesn't scream like it used to(full throttle for rpm) it's down about 200 rpm which is fine with me. It's a 14ft Ashcraft with 2adults and 2 kids and it will do 30mph so that's pretty good.