1987 Mercury 150 Black Max

[fishermanrick]

I have recently purchased a boat that has this Outboard. I am told it has once overheated. With a full charged battery the motor turns over slowly. What could this be and indication of and how should I approach trouble shooting? The Motor has been setting for approximately 2 yrs.

Thanks,

 

[JB]

Re: 1987 Mercury 150 Black Max

First clean up all connections in the battery to engine and starter circuits.

That will probably get her turning faster.

 

[j_martin]

Re: 1987 Mercury 150 Black Max

The starter on it has the brushes on the flat end of the armature, at the bottom. Conductive debris from the brushes fills the space till it shorts out the whole works.

Key off, can you turn/rock the engine easily by hand with the flywheel? In other words is it reasonably free? If so, then brushes in the starter is probably the way out.

Not much wears on them. If the armature isn't torched from trying to start it this way, having the armature faced and a set of brushes should cost you about 30 bucks or so.

hope it helps
John

 

[Boblester40]

Re: 1987 Mercury 150 Black Max

I would take the plugs out and sprya some wd40 or simular down the bores incase they have dried out , its suprising how stiff they can become.

rgds
bob