99 merc 150 efi cutting out and dying at full throttle

[wrestler20]

A friend of mine has a merc 150 that seems like it is not getting fuel. He will be cruising along at WOT and it will just quit. When you go back to the motor the fuel bulb is not pumped up. When you pump it back up it will be fine for another hour or two, then the same thing happends. Any ideas on what to check out? thanks for all of the help you guys give. Hopefully one day i can answer a question instead of asking them. <br /><br />Steve

 

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Re: 99 merc 150 efi cutting out and dying at full throttle

Check the fuel pickup tube in the tank,and the tank vent first,Wrestler. If your friend has an extra tank,and both do this, then it is safe to assume they are ok.<br />Next, check the fuel line for and small holes.<br />If this checks clear, check engine compression.<br />The fuel pump operates on elctric on this model (I think, correct me if not). Check the wire connections to it to be sure they are not corroded, and are tight. If it is a vaccumm operated pump, low compression will not allow it to be operated. It may alsoi have a bad diaphram and/or check valve. One small piece of trash can clog the injectors, so there must be a very good filter inline before the injectors. It will also be a prime suspect.<br />Let us know what u find.