1994 250 Saltwater. Severe Pitting on head

[tenious]

Just replaced the port side head and jacket because of small hole thru both.
Pulled other head and the bottom Cyl. on the cyl. side was severly pitted. The Cyl walls look and feel smooth. Compression was an equal 90 on all 6. Why would this pit. Engine runs rough and all the plugs on the starboard side all are wet. Could this need a complete over haul???

[jb123]

is it saltwater pitting/corrsion or does it look like a ring/piston pieces did itprior ?
if it is salt corrosion then only thing you can do to prevent corrosion is be sure to warm engine enough to open stats when flushing.