Heat Exchanger Zinc
 

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

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.

pop the lid
 

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).

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.

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!

Maybe someone from Moyer can pipe in with what the length of the pencil zinc is required on their unit? I know you can get them in various lengths - why potentially pay more for a longer one that you have to cut?

- Edit - sorry.. I got off my butt and did the looking myself LOL... - https://moyermarine.com/product/sacr...r-cfwc_04_268/

if it's a similar unit to Moyers, maybe these dimensions will help?

https://moyermarine.com/product/sacr...r-cfwc_04_268/

You can buy the zinc without having to buy the brass part. I get my zincs and screw them right into the brass, for about 2 dollars.
even West has them.

The old one doesn't unscrew, maybe made that way, maybe corrosion. The new one does unscrew and I found that by accident.

The one on the Moyer page says overall length 2", length of zinc 1.3". The one I bought at West has 2" of zinc, which they told me was standard. On the bright side, it was only $4.79

Another lesson in the books...