Re: Synthetic oil question
Most who have tried the better quality Synthetic and Synthetic Blend TC-W3 oils have found less fouling and carbon build-up on the two stroke motors of all models.
My personal experience has been excellent - much improved over standard oil in all of my engines.
I have no experience with 4 stroke marine engines, so I can't help with that.
Most of the full synthetic oils are advertised as biodegradable and that is important to me.