Anode-Dissolving Antifreeze?

[ducked]

Came across this while posting on an automotive forum

https://www.commaoil.com/passenger-v...ducts/view/300

The (not very) TDS for this Comma Super Coldmaster stuff (The SDS, often more, though of course still not very, informative, doesn't seem to be there) notes:-

"Avoid galvanised containers for storage or dispensing as they will corrode and contaminate the product."

Oo-er.

This Comma stuff seems to be your "classic" IAT that I understand is usually recommended for marine engines, and probably very similar to the Halfords Silicate stuff I used to flush my raw seawater cooling system before laying up.

I dont have the option of avoiding zinc, since a zinc anode provides essential protection to the engine.

Anode-dissolving antifreeze may not be very important in a raw seawater system, which is essentially an open "total loss" circuit, though it may mean I loose more of the anode while laid up. I'll be checking how much of the anode is left before I run the engine.

Anode-dissolving antifreeze would seem to be potentially quite important where the seawater system has been converted to a closed circuit containing antifreeze, perhaps using a keel cooler.

Is this zinc incompatability a general property of IAT antifreezes?

 

[VicS]

Came across this while posting on an automotive forum

https://www.commaoil.com/passenger-v...ducts/view/300

The (not very) TDS for this Comma Super Coldmaster stuff (The SDS, often more, though of course still not very, informative, doesn't seem to be there) notes:-

"Avoid galvanised containers for storage or dispensing as they will corrode and contaminate the product."

Oo-er.

This Comma stuff seems to be your "classic" IAT that I understand is usually recommended for marine engines, and probably very similar to the Halfords Silicate stuff I used to flush my raw seawater cooling system before laying up.

I dont have the option of avoiding zinc, since a zinc anode provides essential protection to the engine.

Anode-dissolving antifreeze may not be very important in a raw seawater system, which is essentially an open "total loss" circuit, though it may mean I loose more of the anode while laid up. I'll be checking how much of the anode is left before I run the engine.

Anode-dissolving antifreeze would seem to be potentially quite important where the seawater system has been converted to a closed circuit containing antifreeze, perhaps using a keel cooler.

Is this zinc incompatability a general property of IAT antifreezes?

An anode is not required in closed fresh water cooling system filled with an antifreeze solution. If you have converted a direct seawater cooled system you can leave out the anode because the inhibitors in the antifreeze will protect the system from corrosion.
Just plug the hole

 

[ducked]

An anode is not required in closed fresh water cooling system filled with an antifreeze solution. If you have converted a direct seawater cooled system you can leave out the anode because the inhibitors in the antifreeze will protect the system from corrosion.
Just plug the hole

My boat still has the original raw seawater system, so definately still requires the anode, which it seems will be attacked by the antifreeze I put in it for overwintering ashore, as is often recommended.

Perhaps an anode wouldn't be required on a converted system, but this came up in the context of someone experiencing galvanic corrosion of their car engine which this antifreeze, (formulated for this type of engine, and not for a converted direct seawater cooled engine) didn't prevent, so I wouldn't bet a lot of money on it.

https://www.honestjohn.co.uk/forum/post/199321/vauxhall-nova-1200-

There's also the possibility of a freshwater circuit losing integrity due to damage or wear and reverting to salt water, in which case it would be nice if the engine survived for a while.

Possibly a magnesium anode would be a partial solution for a converted system, though I dont know for a fact that magnesium is compatible with antifreeze either.

It would probably erode very rapidly in seawater but might buy a bit of time for an integrity loss fault to be detected, perhaps by monitoring conductivity, or, less benignly, by the system clogging with salt.