1987 Mercury 150 VR2 S/n: OB219718 dies in gear

[miketstratos]

Need help Please, 1987 Mercury 150 VR@ s/n: OB219718, My boat idles and goes into gear at home submerged and with muffs on perfectly, throttles up nice and etc. As soon as I get to lake, usually starts ok, then once warm idles fine. trimmed all the way down and put into gear it wants to die unless I hold the choke in and trim way up, it will then move forward at a snails speed, will die if I give it more throttle. it will start to bogg again so I push choke again, can hear rpm raise and stays running. without pushing choke time to time it will die. Ive rebuilt crabs, replaced fuel lines and primer bulb, replaced fuel pump diaphragm, same issue. I rebuilt carbs first, and later did fuel pump, fuel pump was loaded with sand, Maybe need to do carbs again, since fuel pump may have let something through again even though there is a filter after fuel pump and before carbs? Any ideas? Thanks in advance!!!