I Just bought a 1987 17' BlueFin boat with a 50hp Force motor, model#507F7B w/o power tilt trim. Motor had been stored for several years. Changed gear lube and checked the compression, it was 148 / 150. Also ran in tub of water and had a little stream of coolant water coming out. Went for an outing, motor seemed sluggish but figured it's only a 50hp. I installed a new tach which never did get above 1100 rpm's, new this wasn't right, doubled checked everything, wired correctly. Boy's went tubing for a while when motor severally overheated, when they came back smoke was coming off of motor and had discolored paint on cyl. heads a little. I just checked compression again and it's now 128 / 130. Did we do any bad damage to motor? Should I drop lower unit and check pump impeller? Is this ready or worth rebuilding? Or is motor just undersized for boat. UPDATE: Just pulled lower unit and water impeller looks fine but it is missing the gasket between the s.s. plate and housing. We put a hose on water tube a put a small amount of water to it, seen water coming from side of head gasket, pulled head and removed gasket, found that thermostat was stuck open. Cyl's don't look to bad. Also noticed that when drive shaft was allowed to go all the way down into lower unit it makes a growling sound and feels very rough unless you pull it up a little, them it feels better when turning. Also seen fuel leaking from carb when motor was tipped up. ??? Think this is a basket case ??? I still can't see why it would have over heated. Sorry this is so long but trying to give all the info I can. Thanks
