Slight Bog 3.0 alpha one sterndrive

Hello all, I have a Alpha one 3.0 Merc on a 2002 boat (not sure what Gen, but Manual #26). I have had a slight bog for years now and cannot figure it out. If I ease into the throttle slowly, I have no Bog. If I hammer the throttle as if I were pulling a water skier, I have no Bog. If I throttle down at a normal take off pace the engine bogs down to almost a stall, I then have to pull back on the throttle and prevent the Bog, then it will allow me to take off again without an issue.
Any Idea's?

It sounds like an accelerator pump in the carb. issue? But, if you have a fuel injected engine, I don't know the fix?

Had this problem for several seasons on my 5.7MIE (carbed) engine. It appears as if MERC paints the carbs after assembly and the paint forms a "zero clearance" bearing on the bent rod that connects the throttle to the accelerator pump. In time, the paint chips off and you end up with one or more sloppy holes where the rod connects these two points. When this happens, the throttle arm opens the throttle plate slightly before the accelerator pump squirts gas into the engine causing a bog or a stall. This is only an issue when you throttle up shifting into gear at certain rates. When I posted this issue some years ago a member ( sorry do not remember who!) advised that the "Z" bend in that link rod could be slightly bent (straightened) to take out that slop.

Bingo!

sandkicker said:

Had this problem for several seasons on my 5.7MIE (carbed) engine. It appears as if MERC paints the carbs after assembly and the paint forms a "zero clearance" bearing on the bent rod that connects the throttle to the accelerator pump. In time, the paint chips off and you end up with one or more sloppy holes where the rod connects these two points. When this happens, the throttle arm opens the throttle plate slightly before the accelerator pump squirts gas into the engine causing a bog or a stall. This is only an issue when you throttle up shifting into gear at certain rates. When I posted this issue some years ago a member ( sorry do not remember who!) advised that the "Z" bend in that link rod could be slightly bent (straightened) to take out that slop.

Bingo!

Click to expand...

Where is the accel pump located? You basically straightened that rod a little at a time until you noticed an improvement? Is there just 1 link rod or 2?

Accel pump is located on same side of carb as the throttle linkage attaches. It is a rod that sticks up out of top of carb. It connects via said rod to an arm on the carb quite near where the throttle linkage attaches. As you open and close the throttle, the rod goes up and down. Opening the throttle causes a squirt of fuel to enter the throttle bore. With the flame arrestor (and engine!) off and the choke (if equipped) open, the squirt of fuel is very noticeable. With the engine off, and the throttle cable disconnected, you will notice that very slight openings of the throttle (and throttle plate) can be made without a fuel squirt. This is the key thing to look for if this is your problem. Tweak the connecting rod until you get fuel squirt even with slight throttle opening. A bit of a warning... fooling around with this to debug and adjust it will inevitably cause the engine to "flood"... letting the engine sit with the throttle wide open for a few mins will help the excess fuel vapors to dissipate. Be sure to be running your bilge blower during this.

The rod is "adjusted" in tiny increments until the slop in the linkage is reduced to almost zero.