My Mercruiser 3.0 quit so I bought a 1992 Kencraft equipped with a 1992 Mariner 115 HP engine,also has a 9.9 merc on the back.Several people have told me I will need the 9.9 because the Mariners have a lot of problems.The whole rig has been garage kept and looks like new and well maintained.Does anyone know what the major problems are & the good points of this type of engine.