1999 2800/7.4/B3 Zinc Inventory?

[codingparadox]

Any chance anyone has a full inventory of Zincs to replace on a 1999 2800 SCR with a single 7.4L with Bravo 3? The previous owners of the boat, we're finding, weren't big on maintenance, so I'm trying to get a full list of items together to just change out and start recordkeeping on.

[mmwjr]

Mercruiser/Quicksilver sells the entire set in a kit.

[shrew]

The Bravo III zincs come in a kit from Martyr. Make sure you order to correct kit. One kit is for 1989 -2003. The other kit is for 2004 and newer. The 2004 BIII takes 2 zinc's underneath the anti-ventilation plate. The older style only uses one.

The newer kit also comes with a prop zinc. I would buy the prop zinc separately if the kit doesn't come with one. You'll need to determine whether an Aluminum or Zinc kit best meets your needs.

Magnesium: Freshwater ONLY
Aluminum: Freshwater/brackish water/saltwater
Zinc: Saltwater

Then, all you need at 2 sets of rudder zincs for the trim tabs. For trim tabs I used Martyr CMR-3 rudder zincs.

[codingparadox]

If we keep the boat on Lake washington (Freshwater) but frequently take it out for weekends in the sound (salt water), should we go with Aluminum or Magnesium, since it will spend 95% of its time sitting in fresh water?

[biggerseagar]

Aluminum!


Roger

[codingparadox]

Looking up parts, looks like I can get the B3 kit and a separate prop anode from boatzincs.com (and elsewhere). I'll have to figure out what the right size anodes are for my trim tabs, but lastly, what about on the engine? On our big cummins motors there's a pile of zincs all over the cooling system. I assume there's something similar on the 7.4L with freshwater cooling subsystem.

[mmwjr]

If the engine has closed cooling there should be one anode on the heat exchanger. If open cooling no anodes.

[codingparadox]

Gotcha. Any idea what size it is, or can I tell by looking at it without draining the system to pull it out?

[mmwjr]

No idea, it threads into the open raw water side so no big deal removing it. It will be a brass plug that the anode threads onto.

[shrew]

Originally Posted by codingparadox

I'll have to figure out what the right size anodes are for my trim tabs,

This was already provided (Above)

Originally Posted by shrew

Then, all you need at 2 sets of rudder zincs for the trim tabs. For trim tabs I used Martyr CMR-3 rudder zincs.

[codingparadox]

Oh does everyone have the same trim tab set? The installation looked completely aftermarket on my boat (super shitty wiring/sealing at the tabs), but maybe that's just how them factory boys did it.

[codingparadox]

FWIW for people, the heat exchanger has an E1-size anode. 3/8 NPT fitting, 2" long by 1/2" diameter zinc part.