Yes, Marvel Mystery Oil can be added to your fuel and your crankcase. When added to the crankcase, it will remove any sludge and varnish that may have formed. The crankcase will be cleaned and stay that way with regular use of Marvel Mystery Oil. Since it is a high mileage engine, we would recommend starting by replacing 1-pint of your motor oil with Marvel Mystery Oil. Leave the Marvel Mystery Oil in until your next oil change. At that time, you can up the replacement to 1 quart of Marvel Mystery Oil replacing 1 quart of your regular motor oil.
In your gasoline, use 4 ounces of Marvel Mystery Oil for every 10 gallons of gasoline. The MMO replaces the lost lubricity that has been lost by the addition of ethanol is most grades of gasoline today. It will also reduce friction and help increase fuel economy by cleaning up carbon deposits in the engine.
