Hesitation when accelerating hard

[Wakeboarder141]

Whenever I start to hammer down the boat hesitates for just a second right as I hit the throttle, almost as if it doesn't have enough fuel or something. If I accelerate slowly it doesn't do this. I have rebuilt the carb, changed the plugs, wires, cap, and rotor. What could be causing this? Thanks.

 

[TwoBallScrewBall]

Re: Hesitation when accelerating hard

Some of the merc's came with carbs with insufficently-sized accellerator pumps, that even though are working still don't squirt enough gas. There is an updated carb/pump. Might be the case. Couldn't hurt to double check the pump oueration though. Look down the carb and verify you have good streams of fuel when you move the throttle.

 

[Rhadley]

Re: Hesitation when accelerating hard

What engine do you have? The 120 and 140HP versions with Mercarb carburetors often have this problem, especially pre-1987.

 

[Wakeboarder141]

Re: Hesitation when accelerating hard

The engine is a 1992 3.0L Merc

 

[f_inscreenname]

Re: Hesitation when accelerating hard

Does the lever that moves the accelerator pump have 3 holes in it? If so move the lever in toward the carb one hole.

 

[Wakeboarder141]

Re: Hesitation when accelerating hard

You'll have to excuse my ignorance, but where would I find the accelerator pump to look at that? Thanks.

 

[Wakeboarder141]

Re: Hesitation when accelerating hard

Can anyone explain where to find the accelerator pump? Would I check for fuel spray with the engine running? Thanks.

 

[JStutz]

Re: Hesitation when accelerating hard

I have a 1993 3.0L Merc doing the exact same thing you are describing. There is a lot to be said for fuel injection! I have also rebuilt the carb, changed plugs, plug wires, filters, etc. to find the accelerator pump remove the flame arrestor from the top of the carb. Look down the throat of the carb while some pumps the throttle a couple of times. You should see a strong blast of fuel. You probably replaced the accelerator pump when you rebult the carb. It was the white plastic piece covered with a spring. I noticed the new pump was more "stout" then the old. Unfourtunetly I still haven't found my problem. The only thing left for me to try is replacing the fuel pump. <br />Good luck, let me know what you find when you figure it out!!<br /><br />Jeff