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Home Port: South haven,mi
Vessel Info: 2006 3200 0pen 8.1 crusaders
Well cant seem to open your pics, so not really sure what you mean by oil cooler zincs as the only thing i've seen on oil coolers are water drain plugs and they didnt have a zinc attached like the ones in the coolant heat exchanger.
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Home Port: Long Island, NY
Vessel Info: '95 3100 Open, Crusader 7.4's
I'm assuming you are referring to the U-coolers on the front of each engine. I would try to use a pick & remove any remains of the old zinc, but, as the coolers are pretty much closed vessels, I'd probably leave them behind to eventually be eroded away by the raw water flow. To some degree, whatever is left in there may hinder the insertion of the new zinc & have some effect on future flow until it breaks down further.
The zincs in your pics show them largely intact, but the extensive erosion at the base will only cause you to have the same problem again. That being said, I change mine every season. Very inexpensive & easy to replace. As you may already know, the zinc can be unscrewed from the brass cap & a new one installed, lowering the cost even more.
Hope this helps
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Home Port: NJ
Vessel Info: 2001 Tiara 35 Open Cummins 370
To remove the stuck zinc, cooler removal is probably necessary. I would not rush into that however. What I would do (and have in the past) is insert the new pencil zinc and take the boat for a ride. If the engine is not running excessively hot, leave it be.
I notice your home port is fresh water. In salt water (my home port) I would replace the pencil zincs twice a year to prevent the anodes from breaking off. Going forward, check the anodes every few months and replace as you wish.
Bob
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Home Port: Hudson River / Norwalk CT
Vessel Info: 1994 Tiara 3100 Open
Do you use the same pencil zinc in fresh water as you do in salt water?
Thanks,
Tom
Tom
relatively new to me: 1994 Tiara 3100 Open 454 TBI Crusaders
Lifetime racing and cruising sailor throughout New England
More recent home port is upper Hudson river with our Tiara (closer to home)
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Home Port: South haven,mi
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Should be using magnesium not zinc for freshwater. zinc is almost inert in freshwater.
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Home Port: St. Clair Shores, Mi
Vessel Info: 33 Open 1988 - 454 Crusader 1700 hours
I replaced all mine with Magnesium.
1988 33 Open - 454 Crusader - Trophy Hunter
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Home Port: Lake Michigan
Vessel Info: 52 Sovran, Cat 3406
As an option you could try a product such as barnacle buster. It will probably dissolve what is left of the old zinc and clean out your heat exchangers. Just make sure to remove your new zincs / magnesiums before flushing and reinstall afterwards.