BOATS & MOTORS HOME FAVORITE SUBSCRIBED Boats & Motors oil for motors Pin As Favorite Subscribe to Topic 9/15/21 @ 3:05 PM INITIAL POST hook, line&sinker User since 4/18/07 View Profile Block User I have a 50 hp yamaha engine. Is it necessary to use only there oil for the motor.Thank you LIKE Report Abuse POST YOUR COMMENTS Displaying 1 to 7 of 7 posts SORT DESC Sort by date Descending Sort by date Ascending ALL DATES Displaying 1 to 7 of 7 posts