Hey guys,
I’ve got a ‘12 Mercury Pro XS and want to find out what’s recommended for the best performance for this engine. In the 4 years I’ve owned it I’ve always run non-ethanol with the recommended “cocktail” and 87 octane. I called Mercury and received the blanket statement that it is engineered for 87 or higher. I’ve found other information that states anything higher that 87 creates carbon deposits if you idle most of your time on the water. I have all levels of ethanol free available and don’t mind spending the extra money on higher octane if it provides and longer life and better performance year round.
Thanks in in advance and tight lines!