Thanks everyone - great info, I appreciate it.

Kieth & Jeff, only one end has an end cap.

Dick, I do have the Westerbeke Technical Manual (1975). It includes a
parts list, but although over 250 pages of good information, it leaves
much to be desired. For instance, the heat exchanger diagram doesn't
show a gasket and doesn't indicate that the end with the bolt comes
apart for cleaning (I'll bet it does).

The former owner gave me spare parts that include two different size
zincs. I was wondering why (thanks Gordon). The oil cooler diagram
doesn't show a zinc, but tomorrow, when I look, I'll bet there's
one on it.

Andina, I like your solution - no work involved.

I just got the boat. It was on the Great Lakes and I'm told not too
much attention is paid to zincs on fresh water. That's why I'm
checking them out now. I think what I'll do is not do any flushing.
I'll keep a close eye on the water temperature and take some action
when the boat comes out for the winter next month unless I have an
overheating problem.

Again, I really appreciate the advice and opinions. My last boat had
an Atomic 4 and was basic camping out in the features department. The
new boat is a whole new ball game. So many wires and mysterious boxes!

Paul C - in Connecticut