I have 2 out boards a 1996 yammaha 15hp and a 1996 force 50hp i know the fuel to gas ratio but am not sure about the oil to use <br />tc1 tc2 tc3 is there a difference and can i use whatever one is best in both moters??<br />..And i want to thank everyone who answered last years questions i asked...took both moters out of storage this year and they both started without a hitch!!! THANX GUYS !!!<br />WARRENP