Mercury 50hp running problem

[Tony gau]

" I am having problems with my

" I am having problems with my 1987 red band merc, the engine was running well till I ran out of fuel on one tank( plastic type 30lt ) I tried to change over with the other tank but the motor still run with a big lack of power so i swapped back to original plastic tank. The engine starts first turn of the key and revs up fine with the choke on, when out of water and in gear it revs out easily to 5500 rpm, however, once in the water it wont go above 3000rpm and seems to be starving for fuel. Anyone have some idea of what I can try.
thanks Tony "

 

[msheridan]

" I am in the same boat as Ton

" I am in the same boat as Tony, I forgot to open the vent on my fuel tank and created a vacuum in my system. Motor runs fine in nuetral and revs no problem however under power cant get above 3500. looks like our problem can be corrected by the same procedure. "

 

[Tony gau]

ok so whats the solution ? ca

ok so whats the solution ? can someone help us out here

 

[tom c]

" I too am in a similar situat

" I too am in a similar situation. The motor (70 HP, 1986) starts fine, but won't accelerate under power. Any help would be appreciated. "