gary dicenso
New member
Water in bottom cylinder of my 40 hp early 90's Mercury 4 cylinder outboard serial # OD229057. What could be the problem? I thought it my be a head gasket but was told there my not be any head gasket on this type motor, don't know if its true or not! If there is no head gasket could it be a cracked water jacket or cyclinder? There is 105 psi in all the other cylinders and 100 psi in the bottom cylinder where the water is occuring. The engin runs on 4 cylinders untill the water intrusion stops the bottom cylinder then the engine only runs on 3 cylinders. Please help if you can!! regards!
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