Question Radiator Cleaning Tips

[Aikouka]

I'm curious if anyone has any surefire or really effective methods for pre-cleaning a radiator.

I ask because I'm not sure if I'm just making the task harder on myself, or if it's just par for the course. I usually do a vinegar soak (100%) for about 12 hours, which was then followed up with water-filled shakings that would usually last for 30-60 seconds. I typically use tap water in the beginning and switch to distilled later. In the past, I've also heated up the water prior to putting it into the radiator for shakings. When done with any shakings, I dump the water into a white ceramic bowl to look for flakes. The problem is that I end up having to perform an inordinate amount of shakings to get no flakes. I like Hardware Labs' L-Series radiators, but it literally takes me three dozen (or more) shakings just to get no flakes. (I'm curious if Corsair's XR series is cleaner given they're just HWL's L-Series with a Corsair badge.)

I've seen people suggest using a garden hose to force the gunk out, using things like Mayhem's cleaners, or using a temporary loop with a filter. I haven't tried the former two, but I have tried the loop with a filter, and I didn't notice anything caught. Albeit, that might also mean that I'm going a bit overboard with the number of shakes; I mean... if the pumps can't force water fast enough to dislodge the small flakes, then would an actual loop have an issue?

 

[mindless1]

Are these flakes, corrosion you have caused by soaking it in acid (vinegar), or are they fungus? If fungus, I might try an enzymatic (non-acid) drain cleaner.

What is "pre-" cleaning? Would not it be post- cleaning?

 

[Stuka87]

I am unable to find what these radiators are made from. Their docs say that they have copper fins, but they don't say what the tanks or tubes are made from. Typically they would be brass or aluminum.

But if this is happening to you on a regular basis, it makes me think of a few possibilities.
1: There is some current in the coolant, resulting in electrolytic corrosion. This can also happen if anti-freeze goes bad.
2: Whatever you are using for coolant is becoming acidic over time. Or using an acidic cleaner, like vinegar.
3: You may be seeing what is typically referred to as erosion corrosion. Which is where the coolant is moving fast enough to wear away the oxidized layer on the outside of the aluminum, which then makes it susceptible to corrosion. And since aluminum only oxidizes when its in contact with oxygen, once that layer is gone, it won't return until the fluid is drained.
4: Less likely, but indifferent metals can cause this. But that normally requires the coolant to have metal that reacts with aluminum in it.

 

[aigomorla]

What flakes are you talking about?
You shouldn't get any flakes after the initial flux cleaning done on a new rad.

HWLABS are brass tubes, never aluminum.
Infact all but a few koolance radiators are brass or copper, mostly being brass then full copper except a few like the NeXXXos series.

And no i am thinking those flakes might be from a premix, or a dye deposit.

Personally i just let the rad run in a bucket with tap water with a tube res filled with filter cotton if the rad has been used in a premix coolant situation.

Then i will let it sit in distilled vinegar for about 30 min, and then flush the radiator out, with tap water, followed by a good rinse with distilled, then immediately Cap the inlet and outlet ports so air doesn't immediate oxidize the interior after.

But care to show me pictures of what these flakes are?

 

[aigomorla]

So i did a radiator cleaning today that was going to go in storage....

This is the order I went though.

1. I took a 5 gallon bucket with a Aquarium sump pump that had 1/2 inch fittings on them. They look something like this.

https://www.amazon.com/Submersible-Aquariums-Fountain-Aquarium-Hydroponics/dp/B09ZY93DM9?ref_=ast_sto_dp&th=1&psc=1

The pump sat in the bucket. The radiator i had feeding from the pump and output into the bucket.
I let the unit run for about 10 min to free any loose material that might of deposited in the fits.

DO NOT USE A PUMP WITH HIGH HEADPRESSURE OR A PRESSURE WASHER ON THE INLET AS YOU RISK WARPING YOUR CHANNELS LIKE A BALLON FROM WATER PRESSURE

2. I then went to an autostore to pick up a Prestone Radiator Flush.

https://www.autozone.com/antifreeze-radiator-additives-and-windshield-wash-fluid/radiator-flush/p/prestone-radiator-flush-cleaner-22oz/223022_0_0

You can pour the dilute inside the 5 gallon bucket with fresh water.
Then let the system run again for about 15-30 min. Typically i will use about 1/4 of the bottle with about 4 gallon's of water.
If you notice the solution is running clean after 15 min, your probably done..... if its a little dirty, let it run to 30 and check again for any changes.
If the solution is getting dirtier, then let it run longer.

3. Drain bucket + radiator and rinse out pump with water.
Then refill the bucket with fresh water again, and run the system with fresh water for 10 min to get rid of any residue.

4. fill the radiator half way with distilled... give it a good shake... empty. Repeat this step about 3-4 times, as you want to make sure the only wet solution left in your rad is the distilled.

Then seal the inlet and outlet of radiator after the distilled rinse, and store away, or install in your system.


You do not need to go all out like this, but this is what i did as i retired out a mining rig, that was water cooled, and had to shelf the dual 360's i had mounted on the mining rack.

 

[Aikouka]

Are these flakes, corrosion you have caused by soaking it in acid (vinegar), or are they fungus? If fungus, I might try an enzymatic (non-acid) drain cleaner.

What is "pre-" cleaning? Would not it be post- cleaning?

The flakes existed prior to soaking it in vinegar, but when pouring the vinegar out (and the few cleanings afterward) is when I see the most flakes. I've always read that it's recommended to "pre-clean" radiators due to manufacturing "gunk" being potentially present in the radiator.

But care to show me pictures of what these flakes are?

I can't recall if any have any pictures left from when I was going through the process, but I did purchase two radiators when I was unsure what would fit best in my Meshify 2 Compact. (As a side note, I went with the 280 over the 360 due to better fitment.) So, I do still have the 360 lying around that I could try to clean again. The last time I cleaned them, they had few enough (if any) flakes for me to consider them good, but I'm sure I can get a flake or two out if I shake hard enough.

Anyway, the flakes sort of look like pepper; they're usually small and black. Sometimes, I get larger ones that look a bit more like a very small black paint chip.

 

[aigomorla]

Anyway, the flakes sort of look like pepper; they're usually small and black. Sometimes, I get larger ones that look a bit more like a very small black paint chip.

left over solder flux probably when fusing the channels to the distro at the top and bottom.
The top and bottom is basically like a pan with many holes, they solder and fuse the fins to.
The water builds up in the pans, and then flows down the flat tube channels.

On new rads, the solder can sometimes seep inside and you will get that left over flux.
This is why your correct, we always recommend a good flushing even on a new radiator, to unclog those potential flux, and other stuff which can be deposited so they don't end up traveling to your heatsink and clogging the injectors / base plate.

Nothing to worry about unless your continuously seeing it.
Then it has to be related to the premix your using if at all your using it.
If not, then it could be the plasticizer from the tubing you using, but those would more like like jelly then flakes.

 

[Aikouka]

Nothing to worry about unless your continuously seeing it.
Then it has to be related to the premix your using if at all your using it.
If not, then it could be the plasticizer from the tubing you using, but those would more like like jelly then flakes.

These were brand new radiators, so I had never hooked them up to tubes, and the only thing I ever used in them was water (tap and distilled) and vinegar. My rule with water was to never finish any cleaning "session" with tap water, so I always made sure to use distilled for at least one cleaning at the end of every night. (It took quite a few nights to clean these.) My rule was that I was okay with maybe a few small (pepper-like) flakes, but anything more than that suggested that I needed more cleaning. It also really mattered how much I shook the radiator as a light shake may not result in many flakes, but when I'd shake it like a madman, I might end up with far more. Unfortunately, the latter is also far more (physically) exhausting.

 

[aigomorla]

im fairly sure its just left over solder and flux, and when you shake it harder, its more of it what was left stuck inside.