mercruiser 3.0 engine hesitates

[Blujay96]

I have a 1987 Mercruiser 3.0 4cyl motor. When you take off fast it hesitates for a moment before it takes off. Is that normal or do I need to clean the carb or ?

 

[Haut Medoc]

Re: mercruiser 3.0 engine hesitates

Pull of the spark arrestor & look into the throat of the carb...
Have an assistant pump the throttle....
You should see a stream of gas....
If not, you need to rebuild your accelerator pump....
When was the last time you had a tune up?....

 

[Blujay96]

Re: mercruiser 3.0 engine hesitates

I have only owned it for about half of last summer. So I have not done much to it.

 

[bruceb58]

Re: mercruiser 3.0 engine hesitates

If you really slam the throttle forward, some hesitation is normal. What happens when you smoothly apply throttle?

 

[Blujay96]

Re: mercruiser 3.0 engine hesitates

takes of fine if I smoothly apply the throttle

 

[Haut Medoc]

Re: mercruiser 3.0 engine hesitates

takes of fine if I smoothly apply the throttle

Well, I would say it is normal then...
How often do you put your car's pedal to the floor?....
This is a carbed engine...
I would look to see if the accelerator pump is functioning properly like I outlined earlier....

 

[Blujay96]

Re: mercruiser 3.0 engine hesitates

Thanks I will check it out.

 

[bigskiohio]

Re: mercruiser 3.0 engine hesitates

mine does that to a little ,but i hardly ever crack the throttle. I think they all do it to some extent as there is no instant motion but
mine is older fuel injection probably different.

 

[elkhunter338]

Re: mercruiser 3.0 engine hesitates

Mine also does this. If I apply the throttle aggresively it hesitates some, if I apply the throttle and constant rate and slowly get up on a plan no hesitation. Mine did not hesitate as much when the carb was running too rich, after I leaned the mainjets out to get the plugs to burn clean, then I have some hesitation. Not too bad.
Mine is a 2007 3.0L with the old 1971 vintage carb and manifold. The carb was rebuilt when I got the boat, it was a rebuild carb that had a sticker on it rebuilt.

 

[TFHTECH]

Re: mercruiser 3.0 engine hesitates

if you disconect the linkage from the throtle on the carb. and work the throtle by hand as soon as you move it open the linkage going to the arm that moves the acell. pump must move if theres any lag in movement then it will cause a hesataion you can adjust it by bending the arm to make it longer as you will notice by looking at it, it has a (z) bent into it this is how you adjust it allso you will c 3 holes in the arm on top you can move the acuator to the outer hole to give it more movement. and check the pump as out lined earlyer