Trouble with Starting

I have a 2003 Yamaha OX66 250. It starts like a champ on the first crank when I initially get to the boat ramp, but if I make a run and fish for 20 minutes, the next time I go to start the motor, it could take up to 10 turns of the key before I finally get it started. I replaced the spark plugs, because that is about the extent of my mechanical ability. Any ideas?

Fuel bulb is the first suspect.

If not the fuel bulb then it couple be one of the fuel pumps. My old Skeeter was doing this. Had them rebuilt and problem was solved.

Fuel pump diaphragms need replacing.

This is interesting. I have the opposite problem. Takes me forever to get it started the first time, then it runs great. When I start it to move between spots it starts fine unless I have sat in the same area a long time. Then when I try and start it could take several attempts.

It is almost like there is not enough fuel getting to the motor to start it. I can pump the primer until it gets hard, then it does better starting, but it seems that pressure is not staying as when I check the primer bulb later it needs to be pumped again.

Sound like fuel pump or possibly just the primer bulb?