So I purchased a 1993 Yamaha 25hp 2 stroke oil injected motor and had it out on the lake for the first time this week end. We launched the boat and drove it 1 km to the cottage perfectly. Then we decided to go a little farther to the jumping rocks. On our way there the engine bogged right down but stayed running. I pumped the bulb on the gas line and it revved back up to normal rpm but the bulb stayed collapsed and 30 seconds later the motor bogged down again. I turned around back for the cottage and half way back the engine bogged down even more and quit. The only way I could get it started again after that was to pull the choke all the way and have the warm up throttle all the way up. The whole weekend end when ever I tried to take the boat out for a spin the same thing would happen over and over. I was going to replace the tank and hose but before I do I was wondering if it could be something else like fuel pump, overheating, carburetor, etc..