Zincs in heat exchangers

[chuckg5]

Two years sailing me boat, never knew zincs were in the transmission and fresh water heat exchangers. My rebuild mechanic neglected to mention this.
Ignorance is dangerous and exspensive. Yesterday , found an took off the nuts with no zinc left on them and went to west marine to get replacements.
not bad, 15 bucks. Had to clean out the old zinc stuck in the fresh water exchanger but it went in. the transmission one would not go in all the way, it was to long, I had to cut off over half the zinc to get it in and treaded. the transmission exchanger is much smaller than the larger exchanger.
ANYONE else go thru this? I feel sometimes I come up with this stuff on my own.

[CalebD]

On my friends 32' Endeavor the sticker on the heat exchanger (HX) says to "Check Monthly" right by the zinc bolt (a little over zealous perhaps?).
Yup. More systems and more maintenance is required. Zincs aren't so expensive and are cheap insurance so stock up.
How much does your stuffing box leak?

About 8 years ago I first bought a keel sailboat (Tartan 27') and knew less then nothing about the Atomic 3 or 4 engine but I have learned a bunch about on board engine systems (both gas and diesel) since then.

One great book on boats, engines and their rigging is the Nigel Caulder's "Boatowners Mechanical & Electrical Manual" or some such title. If you are at all 'handy' you could save yourself some boat yard bills by reading this book. It is a bit technical but it is well worth owning and reading.

Which boat make/model do you have? If it is the one in your avatar it is a beautiful boat.

[chuckg5]

Thank you, Caleb
she's a 42 Vagabond cutter ketch 1980 vintage, probably qualifying for the antique catagory. stuffing box no leaky. I posted because I wanted to know if anyone else had to cut the zinc to make it fit. don't seem right. the engine is a ford lehman- made them back in the 60s an 70's then stopped.
Another antique?

[Dfok]

My old boat is new to me, so I ordered the zinc replacement when I changed out the filters and belts. Unfortunately with a pretty soft touch the bolt crumbled leaving the remainder of the zinc as a plug.
I have the liquid wrench and the bolt extractor (for a few weeks now), just need to build up the courage to get into this job one day soon.
All things considered I'd rather be sailing.....

[chuckg5]

that's pretty much what mine looked like. the ends of the exchanger had bolted on end that actually came off with an intact rubber gasket-praying as I unbolted it. that let me clean out the broken, crumbly zinc.

[CalebD]

I've never heard of having to shorten the zinc to make it fit but that does not mean much. It is likely that your transmission zinc needs to be shorter and just may be a harder to find part then the standard HX zincs (they have all 3 sizes at catalinadirect.com).
Have a look at this excellent photo documentary about cleaning up a HX: Westerbeke / Universal Marine Heat Exchanger Photo Gallery by Compass Marine at pbase.com
The thing to do with the HX is to disconnect it from the engine, take it apart and clean out the old rotten zincs that may be in there and then reinstall with new zinc in place. Give it a coat of paint if it needs it while it is out - this can help find any future leaks.

Chuckg5, your Vagabond 42' sure is pretty but my Tartan 27' from 1967 is older by a few years. With automobiles anything over 25 years or so is considered an 'antique'. I'm not sure if it works the same way with boats.

[paul323]

.80 old? Definitely not. '67 old? I think not. Reminds me of an old story about a man who was considering buying his first Rolls-Royce; he found a nice one, but it had 150,000 miles on the clock. He therefore called Rolls-Royce to ask their opinion. The response: "150,000 miles? Nicely run in, Sir".

Traditionally a vintage car is over 20 years old (from the French vingt anees d'age". So I reckon all of you have nicely run-in, vintage boats (like me). And a standard zinc seems to be a bit too long for my Westerbeke deisel too!

[chuckg5]

that 8 week old zinc looked old, that shows how bad the electroylize is going on in there (maybe it can help charge the house bank it I wire it right)
something to keep a closer eye on, something hadn't done for the last 2 years

[CalebD]

I hear that the anit-freeze in the 'fresh water' side of your HX carries electrical current. The raw water side may to some extent as well but not as much depending on salt or fresh water. Since the HX is not necessarily grounded to your engine you need a separate zinc for it as well as your transmission. Electrically grounding your HX to your engine with a wire may or may not help prolong the life of the zinc in your HX. Checking and changing the zinc(s) you can do.

[JiffyLube]

I've heard of some people having to cut shorter engine zincs before.