Recently acquired an older outboard.
Seems to have been very well taken care.
Runs great.
The previous owner ran petroleum 2 stroke oil with no additives.
My question is?
Would switching over to a full synthetic oil and running say a full can of sea foam in each tank (14 gal) for a while clean the carbon out if any?
Your thoughts?

Run two cans of mercury power tune first, seafoam does good keeping it out, power tune gets it out.

They make a spray can for removal of Carbon. Mercury is called power tune. changing to full synthetic oil Is good but sea foam I wouldn't use if any thing run StaBill in your gas.

You’ll get lots of different answers on this, so thought i’d throw one out there. Evinrude Engine Tuner and Mercury Power Tune are pretty much the same thing and do work very well. Follow directions on can, and like what Pat Goff said run two cans right now as a shock treatment.. I like to use a can every 6 months for maintenance. As far as additives, that’s where you’ll get lots of different opinions. I think Techron is a great additive for every tank, but take your pick...

ump Plano Paul