Engine Zinc replaced today
- Thread starter jefndeb
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Jeff
Those that have eroded away are not an issue other than an indication to shorten the replacement cycle. If any break off and drop in I doubt they will erode much as a closed circuit back to the material they are protecting is required to act as an anode and be sacrificial.
I won't claim I've never lost one I couldn't retrieve but I tried to check more often and recently tried a longer rod anode of the same dia on the one that erodes the quickest.
Those that have eroded away are not an issue other than an indication to shorten the replacement cycle. If any break off and drop in I doubt they will erode much as a closed circuit back to the material they are protecting is required to act as an anode and be sacrificial.
I won't claim I've never lost one I couldn't retrieve but I tried to check more often and recently tried a longer rod anode of the same dia on the one that erodes the quickest.
Comodave
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The broken off piece may or may not erode away. It may just collect inside and eventually may block off water flow. I try to get all of them out.
jleonard
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I had one erode and block off the water flow at the entrance to the exhaust manifold on my old Mainship I with the Perkins 160.
You don't want pieces in there to rattle around and cause a problem.
You don't want pieces in there to rattle around and cause a problem.
As noted above, it is not a good idea to leave a broken off piece of zinc rattling around. It is fairly easy to remove the end cap of the heat exchanger to get inside and pull it out.
Presuming it is in the main heat exchanger, look at the tubes when the cap is off for plugged ones. Rod out the plugged ones out and circulate Barnacle Buster, Rydlime or CLR solution to dissolve the scale. A .22 cleaning rod or a length of 1/4" brazing rod will work to rod the tubes out.
David
Presuming it is in the main heat exchanger, look at the tubes when the cap is off for plugged ones. Rod out the plugged ones out and circulate Barnacle Buster, Rydlime or CLR solution to dissolve the scale. A .22 cleaning rod or a length of 1/4" brazing rod will work to rod the tubes out.
David
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Barnacle Buster and other cooling system flushing chemicals will dissolve zincs lost in the cooling system.
The manufacturers recommend removing zincs prior to flushing the cooling system to preserve the zinc.
The manufacturers recommend removing zincs prior to flushing the cooling system to preserve the zinc.
C lectric
Guru
Ditto for the dissolving with some B.B.
You do need to step up the program interval to cut that falling apart to no more.
Judging by the condition they stopped doing any good some while ago.
I smear the pencil threads with a bit of Rectorseal #5 which helps seal the water out of the cap/pencil threads so they are less likely to fall out.
I also tighten them in firmly using pliers and a wrench.
I then check the resistance between the cap and the pencil just to be sure.
They likely, almost guaranteed, will not all last the same length of time so you need to check fairly frequently untill you determine which one disappears the fastest. I change mine at the roughly 50% mark.
When you check them some will look decent untill you brush them or poke at them. That means they are doing the job but it is time for the change as, , at least in my experience, once they reach the apparent 50% they really don't have 50% left. The rate of degredation will increase as there is less material.
You do need to step up the program interval to cut that falling apart to no more.
Judging by the condition they stopped doing any good some while ago.
I smear the pencil threads with a bit of Rectorseal #5 which helps seal the water out of the cap/pencil threads so they are less likely to fall out.
I also tighten them in firmly using pliers and a wrench.
I then check the resistance between the cap and the pencil just to be sure.
They likely, almost guaranteed, will not all last the same length of time so you need to check fairly frequently untill you determine which one disappears the fastest. I change mine at the roughly 50% mark.
When you check them some will look decent untill you brush them or poke at them. That means they are doing the job but it is time for the change as, , at least in my experience, once they reach the apparent 50% they really don't have 50% left. The rate of degredation will increase as there is less material.
kapnd
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It pays to measure the available height in the pencil zincs aperature, and compare it to the one being installed.
Sometimes you’ll need to shorten a zinc before installation, or it will break off when it is tightened down, and while you’re thinking you’ve protected for your regular maintenance interval, not so!
Sometimes you’ll need to shorten a zinc before installation, or it will break off when it is tightened down, and while you’re thinking you’ve protected for your regular maintenance interval, not so!
C lectric
Guru
Good point. A too long zinc may also break a solder joint at one of the cooling tubes causing a leak needing the cooler to be pulled off , taken to a repair shop OR simply replaced. Don't ask how I know.
