BOATS & MOTORS HOME FAVORITE SUBSCRIBED Boats & Motors oil to gas ratio Pin As Favorite Subscribe to Topic 5/12/21 @ 5:31 PM INITIAL POST One shot one kill User since 8/12/02 View Profile Block User I have a 25 hp Mercury. Mid 1990s . I can't remember if it is 40 or 50 to 1 . My Evinrude is 50 to 1 , but I've only used the Mercury a few times . In Premium unleaded gas of course. Thanks LIKE Report Abuse POST YOUR COMMENTS Displaying 1 to 11 of 11 posts SORT DESC Sort by date Descending Sort by date Ascending ALL DATES Displaying 1 to 11 of 11 posts