resently purchased .claimed it was running when parked sevral yrs back.Im not sure that is true.said it only has 400 hrs on it,So i tried to removed the exhaust riser elbow and manifold . 2 of The bolts on one side were broke off and the other side was falling a part crumbling away. And 2 plugs had greenish corrosion on them .i never seen that before.so my question is should I by new parts and repair this motor and hope thats the worst of it . Or get a different one? Maybe a bigger one. This one is a 5.0 mercury.it seems a little under powered to me.what engines would easily swaps out? It will be mostly used in sakk