engine only goes 15mph or so

[gustafsonerik]

Merc 500 75 engine revs fine but when put under load it only goes about 15mph or so compression 120 110 115 125. When i rev it to a certain spot the engine dies out.. however if i prime the bulb it won't die..it has a new fuel pump...any ideas????

 

[tashasdaddy]

Re: engine only goes 15mph or so

fuel supply problem, check for air leaks, starting at the tank, also make sure the vent is open on the tank.