Heat exchanger - how bad is it ?

[Orion Jim]

Originally Posted by Jim Cate

Paint a heat exchanger bundle??

Jim

No, paint the heat exchanger after it's been "rotted" out, inspected, and reassembled.

[undercutter]

Originally Posted by TopperHarley

Hi Folks,

Today I checked the zinc on the heat exchanger for the first time on my new (to me) Catalina 30 Universal M25XPB. The engine is about 3 years old, done 200hrs.

Im unsure of the previous owners standard of maintenance, hence wanting to check the zinc ASAP.

My previous boat was raw water cooled so im not that familiar with HX's.

The entire zinc was gone and the picture looked something like this:



My question... how bad is this ? (I have no overheating symptoms)

Cheers.

If you are unsure of the standard of maintenance that the boat was maintained to then a thorough flushing of both sides of the cooling system should be performed. Based on the photo posted at the very least I would have the heat exchanger cleaned professionally (mine, I would replace). removal will also allow inspection and replacement of hose clamps, hoses etc. which may be poor.

I have found that the worst thing for cooling systems, especially the raw water side, is to not run. best to drain and flush whenever long idle periods are expected. 200 hours in 3 years is not a lot. Is this a new install in the boat or is the boat only 3 years old.

Your engine will never overheat until you need it the most.

[Greatketch33]

Originally Posted by Jim Walsh

No, paint the heat exchanger after it's been "rotted" out, inspected, and reassembled.

I didn't paint the bundle (inside component) but did paint the casing (outside component). Replace the rubber seals too.

I didn't have enough information to decide painting the bundle made sense because of the following thoughts:

Would paint on the bundle eventually gum up and eventually float about the internals?

Does paint on the bundle help or hinder in the heat exchange process and would it matter?

[Snore]

For those of us who are frugal (cheap), remove both end caps from the heat exchanger, cut a wire hanger up and use it to clean each of the tubes.

Then use a vacuum to clean the loosened debris out of the heat exchanger. Then take a garden hose and use it tot blow clean water through the salt water side of the heat exchanger. Vacuum again.

The reason for vacuuming is that if you don't, the loosened debris will collect in the small hose that goes to the missing elbow where it will collect and cause problems. Trust me, I had to fix that also

Be sure to use fresh gasket material when you reassemble the device.