Yamaha 115 Problem

[CFRay]

I've been out five times this season. My 115 Yammy 4S is not running well at times which I think may be fuel line problem. The primer bulb is soft when I start up. I squeeze it a few times, the engine sputters and runs like its fuel starved, then after about 30-45 seconds it catches and runs like a champ. I stop, fish awhile and when I start it up again the same thing happens. Repeat the process.

Any ideas from ya'll will be appreciated. I've replaced the primer bulb, no leaks in the fuel hoses that I can detect, checked the fuel filter(looked new), and checked the plugs(no fouling). My Lund boat has an internal fuel tank.

[humancoldfront]

I also have a yamaha 115 last summer it started acting the sameway then it got to the point where it had no top end at all. It took them 6 week to find the problem.

In the fuel injection pump there is a rubber plug that covers a porting hole.The fuel started to leak pass the plug.Causing the pump to loss pressure. Then it got to the point the plug fell out.Then the pump had no chance of pump enough fuel for it to run at top speed. The technician at the dealer couldn't find the problem.Yamaha sent a technician to find the problem and make the repair.

[marine_man]

Are you squeezing the primer bulb before starting the motor?

marine_man

[CFRay]

Yes I have. It takes several squeezes to feel it firm up. I've also squeezed it after the engine starts while its sputtering. The result is not immediate. It takes some time for it to catch and run well. Until that time it seems like its got an air bubble in the line that has to be worked through before it runs smooth. I just went out in the garage and the bulb is soft. Thanks for the reply.