Reply
 
Thread Tools Search this Thread Display Modes
 
Old 02-11-2024, 06:58 AM   #1
Veteran Member
 
City: Stirling NJ
Vessel Model: 1998 Mainship 31 Sedan Bridge
Join Date: Sep 2019
Posts: 37
Aluminum/Zinc Anodes

Aluminum/Zinc Anodes

I have a 1998 Mainship 31 Sedan Bridge. Unfortunately, this boat did not come with internal strainers on the raw water intake. I have the boat out of the water for the winter and besides replacing the manifolds/elbows, I am installing strainers. Now that I will have internal strainers, my thought is that I will flush the raw water side of the cooling system with fresh water if the boat is going to sit for a week or more. Afte doing some reading it was suggested that zinc anodes (the type I currently use) will not work after being in fresh water and that I should switch the motor anodes to aluminum.

This brings up several questions and is the reason for this thread.

1.) Is there a value in flushing the raw water side of the cooling system?
2.) Which is better for saltwater use, zinc or aluminum?
3.) If I change the anodes in the heat exchangers to aluminum, do I need to change all anodes to aluminum. This boat does have an internal grounding system, so all metal is technically connected. I use anodes on the rudders, shafts, and heat exchangers.

Any advice would be greatly appreciated.

John
jlombardo is offline   Reply With Quote
Old 02-11-2024, 02:53 PM   #2
Veteran Member
 
Captain_Michael's Avatar
 
City: Daniel Island
Vessel Name: Dutchess
Vessel Model: Nordhavn 46
Join Date: Dec 2021
Posts: 32
The running gear sits in salt water. Stay with zinc. There was a recent thread on this forum about fresh water flushing after every use. Worth reading. Consensus was that it probably helped moderate corrision. But again, most of the water flowing through raw water strainers will be salt water, so I would continue to use zinc anodes.
Captain_Michael is offline   Reply With Quote
Old 02-11-2024, 04:22 PM   #3
Moderator Emeritus
 
Comodave's Avatar
 
City: Au Gres, MI
Vessel Name: Black Dog
Vessel Model: Formula 41PC
Join Date: Jul 2015
Posts: 21,063
I disagree since aluminum anodes are good for any water while zinc anodes are only good for saltwater. If you are going to freshwater flush then the zinc anodes will develop a coating on them and become ineffective. You can use different anodes inside the engines and the outside of the hull since they are effectively different bodies of water. But since aluminum are good everywhere I would just go with all aluminum anodes for everything. I use aluminum on the hull and magnesium inside the engines since I couldnít find aluminum in the size I needed, I didnít look very hard though, so I just went with magnesium since I am in freshwater, but magnesium is only good in freshwater so it wonít work where you are.
__________________
Boat Nut:
If you are one there is no explanation necessary.
If you arenít one, there is no explanation possible.
Comodave is online now   Reply With Quote
Old 02-11-2024, 05:26 PM   #4
TF Site Team
 
Bacchus's Avatar
 
City: Seneca Lake NY
Vessel Name: Bacchus
Vessel Model: MS 34 HT Trawler
Join Date: Nov 2014
Posts: 7,770
I agree w Dave. For alternating fresh & salt water or brackish conditions ALUM us recommended.
Look at the Perfirmance Metals website for more info & a great selection of pencil anodes. I posted links in the other anode thread if interested.
__________________
Don
2008 MS 34 HT Trawler
"Bacchus"
Bacchus is online now   Reply With Quote
Old 02-11-2024, 07:14 PM   #5
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in the Great Lakes
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 12,789
I would also go with aluminum on all anodes. I spend about 5 months in fresh, about 5 months in brackish, and maybe a 2 in salt. Much simpler to go with aluminum that works in all. While it may take a little looking, all anodes for our boats are now available in aluminum.

Ted
__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is offline   Reply With Quote
Old 02-11-2024, 09:29 PM   #6
BBS
Member
 
City: Awendaw
Vessel Name: Tiger Paw
Vessel Model: Mainship 390
Join Date: Jul 2021
Posts: 19
Does performance metals sell retail to individuals? I was led to believe they sold to business accounts.
BBS is offline   Reply With Quote
Old 02-11-2024, 09:47 PM   #7
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in the Great Lakes
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 12,789
Quote:
Originally Posted by BBS View Post
Does performance metals sell retail to individuals? I was led to believe they sold to business accounts.
I buy from them directly. Nobody in my area carries there products. I usually do $100 to $200 order to make it worth their while. They really need to open an Amazon store and sell at retail to protect their stocking dealers.

Ted
__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is offline   Reply With Quote
Old 02-12-2024, 07:34 AM   #8
Veteran Member
 
City: Stirling NJ
Vessel Model: 1998 Mainship 31 Sedan Bridge
Join Date: Sep 2019
Posts: 37
I do appreciate everyone's input and will be switching to all Aluminum.

Thanks!

John
jlombardo is offline   Reply With Quote
Old 02-12-2024, 11:24 AM   #9
TF Site Team
 
Bacchus's Avatar
 
City: Seneca Lake NY
Vessel Name: Bacchus
Vessel Model: MS 34 HT Trawler
Join Date: Nov 2014
Posts: 7,770
Quote:
Originally Posted by BBS View Post
Does performance metals sell retail to individuals? I was led to believe they sold to business accounts.
I called them to ask and when they checked my zip code they indicated they did not have a retailer nearby. I've ordered a couple times and they sent them w/o issue.
__________________
Don
2008 MS 34 HT Trawler
"Bacchus"
Bacchus is online now   Reply With Quote
Old 02-27-2024, 08:25 PM   #10
Guru
 
Steve DAntonio's Avatar


 
City: Deltaville
Join Date: Dec 2015
Posts: 1,059
Late to the game but I would second the use of aluminum anodes. However, I have had some cases where aluminum pencils develop a frothy coating, which had no effect on their performance (tested with a ref cell), however, it can make them difficult to remove. Therefore, if you go with aluminum pencils, initially check them monthly to ensure you don't have this issue.

I'm also an advocate of fresh water flushing.
__________________
Steve D'Antonio Marine Consulting, Inc.
https://www.stevedmarineconsulting.com
Steve DAntonio is offline   Reply With Quote
Old 02-27-2024, 08:35 PM   #11
Moderator Emeritus
 
Comodave's Avatar
 
City: Au Gres, MI
Vessel Name: Black Dog
Vessel Model: Formula 41PC
Join Date: Jul 2015
Posts: 21,063
I had a problem from last summers anodes. When I unscrewed the brass plug the anode came unscrewed from the plug and stayed in the aftercooler and in the heat exchanger. One was of course the most, almost impossible, anode to get to. I would have had to remove the aftercooler which was a bear to do. I took the brass plug and ground the outside threads off and ground the plug down to a much smaller OD. Then carefully screwed it back onto the aluminum anode. Then I was able to pull it out of the aftercooler. So on the new anodes for this summer I used blue Locktite on the aluminum anode and screwd it back into the brass plug. I measured the resistance before and after using the Locktite and couldn’t see any difference. I will see what happens after this season.
__________________
Boat Nut:
If you are one there is no explanation necessary.
If you arenít one, there is no explanation possible.
Comodave is online now   Reply With Quote
Old Today, 01:35 PM   #12
Guru
 
fstbttms's Avatar
 
City: Under a boat, in a marina in the San Francisco Bay
Join Date: Mar 2012
Posts: 613
Quote:
Originally Posted by jlombardo View Post
Which is better for saltwater use, zinc or aluminum?
Same same, all samey same. Either are fine and there is no appreciable difference in performance.
__________________
Clean bottoms are FastBottoms!
fstbttms is online now   Reply With Quote
Old Today, 01:39 PM   #13
Guru
 
City: Rochester, NY
Vessel Name: Hour Glass
Vessel Model: Chris Craft 381 Catalina
Join Date: Aug 2019
Posts: 7,474
Quote:
Originally Posted by Steve DAntonio View Post
Late to the game but I would second the use of aluminum anodes. However, I have had some cases where aluminum pencils develop a frothy coating, which had no effect on their performance (tested with a ref cell), however, it can make them difficult to remove. Therefore, if you go with aluminum pencils, initially check them monthly to ensure you don't have this issue.

I'm also an advocate of fresh water flushing.
I regularly get that frothy buildup on my trim tab anodes (aluminum in fresh water). None of my others seem to do it, so it may just be an issue of low water flow across the top of the trim tabs.
rslifkin is online now   Reply With Quote
Old Today, 03:47 PM   #14
TF Site Team
 
Insequent's Avatar
 
City: Brisbane
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 4,245
Quote:
Originally Posted by Comodave View Post
I had a problem from last summers anodes. When I unscrewed the brass plug the anode came unscrewed from the plug and stayed in the aftercooler and in the heat exchanger. One was of course the most, almost impossible, anode to get to. I would have had to remove the aftercooler which was a bear to do. I took the brass plug and ground the outside threads off and ground the plug down to a much smaller OD. Then carefully screwed it back onto the aluminum anode. Then I was able to pull it out of the aftercooler. So on the new anodes for this summer I used blue Locktite on the aluminum anode and screwd it back into the brass plug. I measured the resistance before and after using the Locktite and couldnít see any difference. I will see what happens after this season.
I was surprised to read that you use brass plugs with aluminium anodes. Somewhere recently I read that you had to use stainless plugs with aluminium anodes. I'd be interested in hearing more about this configuration.
__________________
Brian
Insequent is online now   Reply With Quote
Old Today, 03:50 PM   #15
Moderator Emeritus
 
Comodave's Avatar
 
City: Au Gres, MI
Vessel Name: Black Dog
Vessel Model: Formula 41PC
Join Date: Jul 2015
Posts: 21,063
Quote:
Originally Posted by Insequent View Post
I was surprised to read that you use brass plugs with aluminium anodes. Somewhere recently I read that you had to use stainless plugs with aluminium anodes. I'd be interested in hearing more about this configuration.
Not sure exactly what they are, I just said brassÖ
__________________
Boat Nut:
If you are one there is no explanation necessary.
If you arenít one, there is no explanation possible.
Comodave is online now   Reply With Quote
Reply

Tags
aluminum, anodes, fresh water flush, zinc

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 05:07 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012