Well, we now know what was causing the
overheating. When the
raw water hoses were changed. Y the local
service guy, he apparently jammed the hose onto the
water pump">raw
water pump flange and the inner liner of the hose folded over, creating an air gap. Because the
pump was sucking air, not water, it overheated and melted the impeller. The ground up pieces of the impeller actually fell down into the dry
raw water hose and were still there when our new and highly-respected
mechanic took it off. Unfortunately, it also got hot enough that it ruined the
seals and bearings in the
raw water pump, too. That had to be replaced. They had a small
camera on a cable attached to a smart
phone so they snaked it through the raw water system and saw that it was bone dry all the way through. The
mechanic cut off the bad end of the hose, put a little grease on it, and it slid right onto the flange on the
pump inlet with no problem. He pre-filled the pump and the hose with water and as soon as the
engine was started, we could feel the water being pumped through. Looks like it's back in business. ...to the tune of $1700! All could have been avoided with some grease on the hose and flange when the
service tech did the original hose change. Guess the good side is it looks like there was no additional damage to the
engine.