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enigma57
11-29-2020, 04:41 AM
Exploring options to prevent corrosion from electrolysis in cooling system. Along with correct anti-freeze/distilled water mix and possibly an additive to minimize corrosion...... I am looking at sacrificial anodes. I understand there are both zinc and magnesium anodes available for marine engines, so am looking at these......

https://www.westmarine.com/buy/sierra--zinc-pencil-anode-for-onan--13482120?cm_sp=Onsite-Recs-_-DY-_-PDP

Son's 350 engine will have iron block, aluminum heads and intake manifold. My 292 inline 6 is all iron...... Will not have any aluminum parts in contact with engine coolant but I am looking into this anyway. Both will run copper/brass radiators (no aluminum radiators) but whatever is shared in this thread should certainly be helpful to those who do.

What are y'alls experience and thoughts on this?

Thanks,

Harry

BamaNomad
11-29-2020, 05:29 AM
Harry, You wrote (in part)

"Son's 350 engine will have iron block, aluminum heads and intake manifold. My 292 inline 6 is all iron...... Will not have any aluminum parts in contact with engine coolant but I am looking into this anyway. ..."
--------------------------------------

Am I mis-reading or did you mis-state something? Engine coolant flows thru both heads and the intake manifold...

PS. I bought a Z28 in the mid seventies (of course with Aluminum intake), and when I tore it down for rebuilding right after purchase, I found aluminum deterioration in the coolant flow ports... Not knowing what had been done to or used in the engine in the past, I attributed that deterioration to 'dissimilar metal' corrosion...

enigma57
11-30-2020, 12:57 PM
I believe you are correct regarding the corrosion in your Z28's cooling system, Gary. Dissimilar metals where there is electrolysis at play...... The metal most prone to corrosion becomes the defacto sacrificial anode for the other. What we will be doing is introducing a zinc piece to become that sacrificial anode and save both the aluminum and the cast-iron that is in contact with engine coolant.

What I meant about my son's engine and mine is that he will have both aluminum and cast-iron in contact with engine coolant, but my 292 inline 6 will have only cast-iron in contact with engine coolant. So son's engine will be more at risk of corrosion than mine. But I would like to protect both.

Best regards,

Harry

Dave the Wave
12-05-2020, 05:42 AM
just checked my reading, as i do periodically. it`s at .03, and it`s a small block, cast, with aluminum radiator and intake. i think the reading should be under 4.0.

Dave the Wave
12-05-2020, 05:44 AM
max should be .30, just looked it up, sorry.

BamaNomad
12-05-2020, 05:55 AM
Dave, It's early in the morning, and I'm at least half asleep... but I'm *lost* as to what reading you are measuring/referencing as being a max of 0.030?? 0.030 ? what? units?

Dave the Wave
12-05-2020, 03:26 PM
you could check this in your system. volt meter, negative to battery terminal, positive in the coolant, not touching anything but coolant. max reading of .30 is good. i just stated that mine was .03 . and, bama, as you know, i watch the cooling system closely. and in my system, about 2 qt. anti-freeze, distilled water, and a bottle of water wetter for corrosion and lubricant.

Dave the Wave
12-05-2020, 03:30 PM
and , enigma, don`t look into this too deep. use a corrosion fighter if ya arn`t running straight anti-freeze. just check it now and then. i do mine maybe 3 times a year. no big deal.

BamaNomad
12-05-2020, 09:53 PM
So you are reading the 'voltage' of the coolant relative to the negative side of the battery? I'm just guessing but I think the 'age' of your coolant probably has a large influence on that value...

LEE T
12-05-2020, 10:29 PM
Is Evans Waterless Coolant Right for My Classic Car? (evanscoolant.com) (https://www.evanscoolant.com/blog/is-evans-waterless-coolant-right-for-my-classic-car/)

BamaNomad
12-06-2020, 06:19 AM
I'd never heard of Evans waterless coolant before Lee... but I read much of the information at the link you included. Do you use it? or have friends that use it? *wondering about the user feedback*?

I looked for it online and found it available (full conversion kit for small block chevys) on Amazon for $299, which included 3 gallons of the Prep, and 4 gallons of the coolant.

Most 'user feedback' I found was from racers...

LEE T
12-06-2020, 07:26 AM
I guess its mostly used to keep the engine running cooler, and probably hard to justify the cost for corrosion resistance. I put it in a freshly rebuilt engine about 15 years ago, but pulled the engine out shortly after that, so I can't give you any feedback.

Dave the Wave
12-06-2020, 10:57 AM
i have zero experience with it.

enigma57
12-16-2020, 12:59 AM
Thanks for your comments and tips, guys. Much appreciated. I will probably stay with a mix of traditional 'green' anti-freeze topped off with distilled water and install a couple of the zinc sacrificial anodes as a hedge against corrosion.

The Evans waterless coolant sounds a bit like GM DexCool and after reading the info in the link, probably not for me.

Son's engine will have an aluminum intake and aluminum heads though, so we will check into various other types of anti-freeze as well before making our decision on which of these to run in his car.

Happy Motoring to all,

Harry

LEE T
12-16-2020, 03:42 AM
I have heard that changing the antifreeze every two years prevents the Alum corrosion

enigma57
12-23-2020, 01:43 AM
That is something I must admit to letting slip by on our older cars, Lee. Thanks for the reminder. I have typically been a stickler for changing oil and oil filter at regular intervals. But changing engine coolant on a regular basis is something I must make a point of doing. My wife's car uses a pink coloured coolant only available from the dealer which cannot be mixed with water nor other type coolants. Its like DexCool that way. Only without the problems so long as directions are followed.

I have thought about using this in my '57 and recommend it to my youngest son for his Camaro, as well. Dealer has no recommended periodicity for engine coolant change (which I find rather strange). Manufacturer of this engine coolant says change it every 100,000 miles or every 15 years, whichever comes first. But I am concerned about flushing contaminants out of the cooling system, so it may be better to stay with the 'green' stuff and change it every few years. Still debating which way to go on that.

Thanks,

Harry

enigma57
12-24-2020, 04:52 AM
Have continued researching engine coolants. Looking for a good coolant that will last a while and help prevent corrosion in son's new 350 engine with aluminum heads and intake. Finally settled on this......

VW - Audi aluminum compatible ethylene glycol type (same as my wife's 2013 VW Passat uses). VW - Audi part number G013A8J1G (concentrate). This to be mixed with distilled water. Anywhere from 50 - 50 to 70 - 30 coolant to water ratio. Be sure to flush cooling system with water thoroughly priour to installation and do not mix with any other type of coolant. This coolant is a sort of pinkish red colour.

Surprisingly, VW has no recommendations as to changing interval, but the coolant manufacturer recommends flushing system and changing coolant at 100,000 miles or 10 year interval, whichever is reached first. My wife's VW Passat has 138,000 miles on odometer at present. We take it to the dealer for regular maintenance and thus far, they have not changed the coolant since new. Still clean and works good as new. As added insurance, we will also install 1 or 2 of the zinc sacrificial anodes in son's 350 engine cooling system for good measure.

Happy Motoring,

Harry

LEE T
12-24-2020, 05:00 AM
the coolant manufacturer recommends flushing system and changing coolant at 100,000 miles or 10 year interval, whichever is reached first.
They probably recommend flushing before you start using it also, unless the engine is new.

Dave the Wave
12-26-2020, 02:50 AM
those anodes are not needed if you just check the level of/if any electrolosis in the system.

enigma57
03-10-2021, 12:49 PM
That's a good idea, Lee (flushing system). Even with a new or freshly rebuilt engine.

Dave, from our experience running the VW - Audi part number G013A8J1G engine coolant in my wife's car over the past 8 years and 140,000 miles, I'd say you are right about the artificial anodes. Of course, it is formulated to run in aluminum engines and her engine and radiator are both aluminum.

Son's engine will have dissimilar metals in contact with coolant though (cast-iron block, aluminum heads, intake and thermostat housing, copper/brass radiator). So we will likely use a couple artificial anodes as added insurance (can't hurt, might help). They aren't expensive and with a bit of thought, we may be able to position them so they can be checked when radiator cap is pulled.

My 292 inline 6 will only have coolant in contact with cast-iron head, block and thermostat housing, though. And a copper/brass radiator. Only aluminum will be the rocker and tappet covers and intake manifold and the intake on these engines has no coolant passages. So I have more engine coolant options than with either my wife's aluminum engine or our son's 350 engine with dissimilar metals in contact with engine coolant.

Thanks to you both for all your help. Much appreciated,

Harry

Dave the Wave
03-10-2021, 02:30 PM
again, don`t look to deep into this. just check it twice a year.

enigma57
03-16-2021, 02:34 AM
Thanks, Dave! Will do!

HB