Help identifying possible radiator leak

Doing a full tear down of my loop after around 2 years of use, using 2x EK copper GPU blocks, EK Supremacy Acetal/Nickel CPU block, D5 pump, de-mineralised water and a silver kill coil (no dies or additives), 240 and 480 HWLabs SR1 radiators. Loop has been refilled twice in that period with new water.

The (presumably nickel) plugs in some of the EK components looked to have corroded somewhat since they were put in, their surface being very rough and no longer shiny, the Nickel CPU block also had some obvious discolouration - in some places all the way down to copper below the plating. The copper GPU blocks when last disassembled had some mild discolouration, partially removed by just rubbing with some wet paper towel. None of the Bitspower 'silver shining' fittings showed any meaningful signs of corrosion.

After flushing out the rads, there were some very tiny 'dark' particles in the water - so small it seemed more to affect the colour of the water than being clearly visible particles.

Image too big to embed:

This residue and paint bubbling is on the bottom of the end tanks of the 240 radiator at the lowest point in the loop. Does this look like a pinhole leak due to corrosion? There was no signs of water residue on the case or fans, or around the fittings on the opposite (upwards facing) side, and the inside of the end tanks look pretty normal.

Any help would be much appreciated as I plan to re-assemble everything in the next few days.

Yeah, I mean that looks a bit rough. Can't tell how that's all assembled. A more distant image along with the close up would be nice.

My oldest 4-5 yr old SR1 (360mm) still looks good as new other than some of the fins. To me that looks like something might have scratched it pretty well from the outside otherwise I feel if it was internally, you'd surely be leaking and it should've been visible but than again, if its corrosion eating it up inside, I guess that could be possible as well.

Are there other sides like that other than that section?

I'd sand it or take a small pick to it and see what's under those spots. Won't know till you do that IMHO. I don't think it's on the inside, I think it's left over from the assembly of the rad. Did you notice it when you built it and you're sure it wasn't there before?

Just looks like an issue in the painting process to me.

This is the case layout since it first went in:


The 480 rad at the top of the case has a couple of very, very slight blemishes (no big spots, only some slight 'bubbles') also on the 'bottom' of the end tank which faces upwards in the case.

I'm in the process of changing the loop arrangement currently, but it's entirely possible the blemishes have come about from having some of the PSU cables sitting under the end tank all this time, vibrations or even damage from installation (getting to the PSU connectors is a very tight fit).

I cleaned back a few of the larger 'spots' with a q-tip and it just looked to be clean metal, have left some water sitting in it and spotted no water coming through, and even pressurised it slightly by blowing into the rad with the other port sealed and there was no hissing or signs of air leakage.

Plan right now is just to add some EK Ekoolant EVO Clear Concentrate to hopefully prevent any further corrosion (if that's what it is) and keep an eye on that particular location. Thankfully it's positioned somewhere it is very unlikely to leak onto other components.

it just look like they did not get it clean enough before they painted it.

A little bonus for anyone helping out, here is the reason for the loop teardown. D5 Pump shat the bed =(

Oh wow. I couldn't fathom what that poor pump was going through. Do you know why it failed?

As for the rad, I think the guys are right. It either wasn't smoothed out right before painting or it got dinged during the installation.

Overall, nice clean looking setup.

After removing the pump from the pump top, it showed the rotor to be scraping against the motor housing for a consistent area in its rotation, had had no issues at all until it started making a horrible rattling sound when I was gaming. Not sure if its due to an issue with the magnets inside the motor, or if the bearing ball or plastic it sits on has worn down at a specific location. I gave draining and re-filling a go, and changing the pump speed but it was rattling no matter what.



Appreciate all the help and feedback!