2001 carbed 5.0 mercruiser sluggish acceleration until 3,000rpm!!

[mhernandezt204]

Ive got a 2001 Tahoe with a 5.0 mercruiser with a carb, more often then not lately but still intermittent very sluggish at wot until it reaches 3,000rpm. forget trying to pull anyone out of the water on skis or a wakeboard! new cap and rotor, fuel water and carb fuel filter looked great any help is much appreciated thanks!

 

[alldodge]

Ive got a 2001 Tahoe with a 5.0 mercruiser with a carb, more often then not lately but still intermittent very sluggish at wot until it reaches 3,000rpm. forget trying to pull anyone out of the water on skis or a wakeboard! new cap and rotor, fuel water and carb fuel filter looked great any help is much appreciated thanks!

:welcome: to iboats

Have you checked timing and fuel pump pressure?
What do the plugs look like?

 

[Bondo]

Ayuh,.... Welcome Aboard,..... Sounds like a Carb issue,..... Spark plug Color oughta give ya some Hints,....

Do a Compression Test, while yer checkin' the plugs, anyways,....

 

[mhernandezt204]

I haven't checked either of those, timing or pressure what is the spec for fuel pressure? Plugs looked pretty good I thought, I was kinda thinking a carb issue myself, but I will check timing and fuel pressure and go from there thanks!

 

[XiViperI]

If all else checks out ok could just be the accelerator pump in the carb. Remove the flame arrester and have someone hit the throttle, you should see the carb squirting fuel into the throat.

 

[Maclin]

Does sound like the carb accel pump needs some work. If this happens when you mash the throttle to WOT, what happens if you move the throttle slowly up to WOT? It should act a little bit different. Also, does it spit back thru the carb sometimes when you mash it to WOT?

 

[alldodge]

I haven't checked either of those, timing or pressure what is the spec for fuel pressure? Plugs looked pretty good I thought, I was kinda thinking a carb issue myself, but I will check timing and fuel pressure and go from there thanks!

Should be 4-7 psi at idle

 

[mhernandezt204]

Hadn't thought about the accel pump but definately makes sense, I'll do some check and see what I come up with thanks everyone! I'll let you guys know

 

[mhernandezt204]

Hadn't thought about the accel pump but definately makes sense, I'll do some check and see what I come up with thanks everyone! I'll let you guys know