Jeff wrote in :

I had chronic overheating problems with a Yanmar 2GM20FC. Everyone I
talked to said it was the the exhaust elbows or the props or high
output alternator. Finally I stripped down the head exchanger and
found some eel grass had reduced flow 50%. Works great now.



I don't understand them when they tell people this. An overloaded diesel
produces huge clouds of BLACK SMOKE, not overheating. As it bogs, it
creates overinjection in naturally aspirated diesels. Smoking like hell,
it doesn't overheat.

--
Larry