Force 5 150hp - bottom 2 cyls not working

[randrews45]

My mechanic found that the bottom 2 spark plugs do fire but are completely clean while the other plugs show wear and carbon. Suspect bottom carb, what are potential problems that could keep carb from working?

 

[sony2001]

Re: Force 5 150hp - bottom 2 cyls not working

Switch the coil wires & see if it runs perfectly. Do you have 3 carbs for 5 cylinders?

 

[sony2001]

Re: Force 5 150hp - bottom 2 cyls not working

Read you post further down. Do check the input wires to the bottom CD, they may have been switched accidently. Quicksilver Power Tune is a good decarbonizer. Follow instructions, using less than they say. Don't breath it!!!!! And even put it in thru the spark plug hole for an overnight soak. After a skeg breaks make sure the prop shaft turns true. The skeg itself is not important.

 

[12Footer]

Re: Force 5 150hp - bottom 2 cyls not working

The clean plugs could've been cleaned by steam,indicating water injestion. These engines are notorious for leaking at the port plate gaskets...A cheap enough fix, but time consuming,and critical torque tolerances. Also, could be head gasket.