This is the thermostat and gasket for the Universal 5411 sea water cooled diesel engine. The factory part number is 275965. Since the 5411 is a sea water cooled engine, this thermostat opens at 140 degrees rather than the typical 160 degree thermostat used in a fresh water cooled engine.
We are embarrassed by the high price of this part. We're sorry! We suspect that, since the engines have been out of production for decades, Westerbeke can only commit to a very small batch at a time from their thermostat vendor. That would explain the price differential between this and the more popular #Z2683 thermostat used on most freshwater cooled Universal engines.
We have noticed that other thermostats we carry will occasionally show up from our vendor with slight variations in the appearance due to subtle design changes, so please understand that the thermostat you receive might appear slightly different than pictured above.
• Catalina 27
• Catalina 30