Heat Exchanger Zinc

[sdemore]

I bought a used heat exchanger last year from a working boat (same model sold on the Moyer site). I pulled the zinc out to replace it today and it is about half the length and thickness of new. I picked up a new on at West Marine and tried to install it today. It went in about 3/4 of the way and hit something inside the exchanger. So 2 questions:

1) should a standard 2" long zinc fit, or is it supposed to be trimmed?

2) Presuming it should fit, if I remove the bolt on top and/or bottom cover, can I pull out the tubes and see if a chunk of old zinc is in there?

[joe_db]

Originally Posted by sdemore

I bought a used heat exchanger last year from a working boat (same model sold on the Moyer site). I pulled the zinc out to replace it today and it is about half the length and thickness of new. I picked up a new on at West Marine and tried to install it today. It went in about 3/4 of the way and hit something inside the exchanger. So 2 questions:

1) should a standard 2" long zinc fit, or is it supposed to be trimmed?

2) Presuming it should fit, if I remove the bolt on top and/or bottom cover, can I pull out the tubes and see if a chunk of old zinc is in there?

1 - don't know, you can trim them
2 - I would look in there and see

[Al Schober]

There are two types of replacement zincs. First comes with the brass threaded plug - not sure how the zinc in secured into the brass. Second type the brass plug is threaded and you just replace the zinc, which has a male thread to match the female thread in the plug. If things fit, the second type is less expensive to replace.
As for the length of the zinc, I recall having to trim the zinc to fit.

[Marty Levenson]

If it is anything like the one Indigo sells it is easy to open. I would certainly open it up and have a look.....especially as you don't know its history. Could even be it is not screwing all the way in due to zinc goo building up in the threads (as it did on mine).

[sdemore]

Thanks for the advice guys! I'll pop it open and see what I can see! It's been cold (frozen water cold), so I haven't been working on the boat as much as I need, so I'll open the heat exchanger at the next opportunity.

[sastanley]

If the threads match up, typically 1/8" NPT, there is no problem cutting some length off the zinc itself. I had to do that to fit in my HX. I probably used a hacksaw or dremel tool. Which reminds me, if I can't remember what I used to cut it, I probably need to replace it!