Water Pump on the Yanmar 3jh3
Bob Bierly

2/21/2002
Hull #: 255

You are probably aware that Catalina started putting Yanmar 40hp model 3JH3BE diesels in later C380s. My hull is #255 and has this engine. After about 450 hours on the engine, I started getting big-time water leakage thru the seals on the pump. The local Yanmar dealer in Cocoa Florida (where I was when I finally started looking for replacement seals) informed me that:

(1) that pump shouldn’t leak with that few hours of wear and,

(2) that he had encountered several pumps on the 4jh and 3jh Yanmars that were assembled at the factory without a required mechanical seal. Bottom line for me was that the dealer removed the pump, confirmed the internal mechanical seal was not installed, rebuilt the pump and reinstalled it all under warranty.

The only fly in that ointment was that the dealer