Heat exchangers- when to replace?

[Rodd]

Thinking about heat exchanger replacment this winter. I have 3 on a Westerbeke 58, oil, transmission oil, and engine coolant. The engine cooler has end caps that I am able to inspect and I can see the passages are clear. In addition the engine cooler has a zinc anode that I replace as needed. The other 2 coolers have no anodes to replace, and one of them is raw water cooled.

These three have been in service for almost 20 years. They are cupro-nickel, and I bought these to last--as they certainly have! Is there a maintenance period where I should replace any, or all of these? I was thinking of replacing the 2 oil coolers, and waiting on the engine cooler. Is this a good strategy? Or do people just keep using the coolers until a problem arises? I try to prevent problems!

Thanks.

 

[Slow lane]

Mine on my power boat will be 38years old this winter. Give it a good cleaning every year it looks the same inside as it always has. I would open them up if possible to get a good look at them. You can pressure test them or have a rad shop do it for you. I test mine at 15lbs every 4 or 5 years if I think of it. My old white 6cill diesel is open vented on the hot side so 15lbs is more than enough.