140 Merc Distributor dust

[vstol]

I have a 1982 140 Mercruiser I/O engine that is getting some kind of black dust substance instide the Distributor Cap, there does not seem to be any wear within the cap when you wipe the dust out. The texture of the dest reminds me of ground up lead like inside a pencil sharpner with out the wood shavings? Any idea on what that could be and whats causing it?

 

[WillyBWright]

Re: 140 Merc Distributor dust

That must be the center commutator brush that disentigrated. There's one under the center post of the cap to contact the center of the rotor. See if that's still there. It's spring loaded and made of graphite ... like a pencil lead.