1980/260 mercruiser. Spent the winter going through the boat. New coupler, motor mounts, Hyd hoses, gimbal bearing, bellows,shift cables, raw water pump and complete tune up. No hurry, worked on it when I felt like it. Got it running, and had to shut it down in the driveway as it was starting to overheat. Exhaust manifolds were boiling. Checked in coming pressure and it was low. I went directly to the AFTERMARKET RAW WATER PUMP. Went and bought a new Mercruiser impeller. Better but still got hot. Went and bought a complete Mercruiser raw water pump. Problem solved. There is a lot to be said for OE parts.
