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Old 09-25-2015, 09:49 PM   #21
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Getting back to zincs, sealant is fine, but don't be tempted to use teflon tape as it will interfere with conductivity.
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Old 09-25-2015, 10:02 PM   #22
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Since you guys are talking anodes, do you use shaft zincs with the copper crush contacts?
Do you even know what I'm talking about?
The reason I ask is that I sell Camp brand anodes that do have the contacts. The local divers don't buy them because they are not the cheapest available. If the copper contact isn't important to you guys, maybe I can switch to a less expensive brand.
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Old 09-26-2015, 07:31 AM   #23
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Since you guys are talking anodes, do you use shaft zincs with the copper crush contacts?
Do you even know what I'm talking about?
The reason I ask is that I sell Camp brand anodes that do have the contacts. The local divers don't buy them because they are not the cheapest available. If the copper contact isn't important to you guys, maybe I can switch to a less expensive brand.
Yes I know what you're talking about. And yes I've used them.
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Old 09-26-2015, 01:18 PM   #24
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I think that the crush contacts are an important feature and I would pay more to get them.

If you just bolt up a non contact egg anode, it may not make good contact with the shaft. The crush contact concentrates the force at one point so it makes good contact.

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Old 10-03-2015, 05:35 PM   #25
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For the past two years I have been unable to get the shaft anodes with the copper contact. What I can get is an egg shaped anode with a hinge system that provides a larger surface of the zinc in contact with the shaft.\There is a difference. I haul once a year, not always at the same time. In the summers, I always get to dive and inspect. The copper crush kind have never, NEVER presented for a summer inspection. Last year was the first year with the hinge kind, and some zinc was still there for my next haulout, 14 months later. I won't be going back to the copper contact kind if I can control it.
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Old 10-03-2015, 06:42 PM   #26
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Greetings,
Mr. K. Sounds like the crush type may have been doing it's job better than the hinge type.
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Old 10-03-2015, 08:04 PM   #27
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For the past two years I have been unable to get the shaft anodes with the copper contact. What I can get is an egg shaped anode with a hinge system that provides a larger surface of the zinc in contact with the shaft.\There is a difference. I haul once a year, not always at the same time. In the summers, I always get to dive and inspect. The copper crush kind have never, NEVER presented for a summer inspection. Last year was the first year with the hinge kind, and some zinc was still there for my next haulout, 14 months later. I won't be going back to the copper contact kind if I can control it.
if it is being dissolved, it is doing it's job. If it is still there after 14 months, it's not doing you any good. You might want to use a VOM to see what the voltage it reports.
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Old 10-03-2015, 10:17 PM   #28
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Wouldn't zinc deterioration be related more to engine hours rather than calendar?


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Old 10-03-2015, 11:03 PM   #29
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Greetings,
Mr. JD. I think zinc depletion is a function of current density rather than time or engine use.
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Old 10-04-2015, 08:14 AM   #30
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Wouldn't zinc deterioration be related more to engine hours rather than calendar?
A zinc is a sacrificial anode to balance the electrical potential of your boat. It is installed to let the free electrons eat on the zinc, rather than your boat's running gear and thru-hull fitting, etc.

Once the zinc is depleted (eaten away) the electrons go to work on your boat parts.

There are lots of things that cause zincs to be eaten away, boat hull material, salinity of the water, stray currents from bad electrical wiring (on both dock and boat), and flow of water over the surface of the boat. The faster you go, the higher electrical potential it builds and faster the anode will erode.

Best thing to do is test the electrical potential of your boat regularly using a silver/silver chloride reference electrode and a volt meter. You hook the reference cell to the volt meter positive lead and the ground lead to a known ground and see what the display reads. This is also a good way to test for stray currents in both your boat, other boats, or the dock power system.
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Old 10-04-2015, 09:45 AM   #31
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Zinc holes are tapered thread as I recall. So if tightened properly they almost never leak. If you're worry about leakage and inhibiting electrical contact, just don't put sealant on the first few threads of the plug.

True, they are called NPT, national pipe thread and are tapered to create a seal. Tightening distorts the threads on the brass plug and creates the seal. IMO they are designed for single use.
Reusing the plug again may not create the same distortion and seal. I little rector seal will help.
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Old 10-04-2015, 10:06 AM   #32
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When changing engine zincs, it's good to chase the NPT threads with a tap to clean things up. A little sealant is a good idea. I've checked with an ohm meter and NEVER seen one insulated.

My engine zincs last between 6mo-1yr. Fortunately, only two. Some Cats are annoying with zincs everywhere.

I too use the shaft zinc and was dismayed by the lack of the copper balls. But after changing my shaft zinc a few times while diving, the ones without the balls are working just fine. Half or more eaten up at change. I do clean the shaft real well before mounting and also noticed that it has a real good grip on the shaft. I don't worry about the balls any more.
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Old 10-04-2015, 11:36 AM   #33
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Rt and Stubones. I understand about the effect of the electrical potential on zincs, but all things being equal (I.e.electrical potential) a pencil zinc in a vessel in use should deteriorate faster than a zinc when the vessel isn't in use: 1) the concentration of zinc in within a heat exchanger has to be higher when the water inside is stagnant than when it is flowing, hastening deterioration; 2) the associated erosion from flowing water is higher than with stagnant water. I check my zincs more frequently in the summer when the vessel is in use than when it is sitting at the slip.


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