[iamhollywood5]

I have a couple of EK radiators made of brass. I had been using a dark red EK premix coolant for a few months and when I took the whole system apart, the coolant had badly stained everything it touched. I was able to clean copper, nickel, and acrylic parts, but I cannot get the brass inside my radiators clean. The surface of the inside is still stained red.

I've let them soak overnight filled with 75% white vinegar / 25% distilled water. I've even let them soak for an hour with 100% vinegar. And I've connected them to a makeshift loop with a pump to run a 50/50 vinegar + distilled water mix through them and let it run for long periods of time, several times. The first time I tried flushing them with vinegar, it pulled up a lot of red that pure distilled water could not get. After flushing and re-filling a couple times, it stopped pulling up red stain and the mixture remained clear, but the inside of the radiator STILL has red coating the inside.

I really wanna get these things sparkly clean with not even a hint of dye stain. Any suggestions? Does Brasso come in liquid (not cream/paste) form? If so, would it be safe to fill up my radiator with it?

 

[Bit_reaper]

Really if pure vinegar does not do the trick I would just leave it as is. Far more risk then its worth. As the color refuses to come off then whats the problem? It won't color the new liquid when you use them in a loop and the staining won't impact performance in any measurable way.

If you absolutely must get them clean no mater what I guess you could try some more powerful solvents like turpentine or acetone. But thous are strong stuff and I'm not sure how they will react with soldered brass. Acetone especially is really potent and will strip paint of metal in seconds so don't go splashing that around. Again not sure how that would react with the solder joints so use at your own risk.

 

[Buzz247]

Dunno I would go for acetone as it is destructive and not sure it would remove the staining.

Using water, vinegar or citric acid, and a bit of salt is the best option. If you are truly desperate, you can try copper brighteners, which are basically a very weak solution of hydrochloric acid. I would avoid the metal polishes like you mentioned above. The residual effect of those will impede future use of the rad and thermal properties, not to mention risk reactions in the system loop later.

Another thought is Purple Power or Castrol Super Clean ( available at local supermarkets) They are butyl based cleaners - very harsh on brass!! - but both can be easily cut with water. If you have a couple of stop plugs, plug up the rad on one end, fill with above cleaner:water at a 1:4 or 1:6 ratio, and plug top up - let sit for awhile (few hours) and checked. basically, get it out of there and rinse/flush as soon as desired results are achieved. You can easily destroy a rad if not careful

 

[iamhollywood5]

Thanks for the tips guys. I don't wanna do anything that would damage it, so I'll just try adding some salt and then heating up the mixture before running it through the loop, and if that doesn't do it I'll stop there. I'm just a picky perfectionist and I really don't want the remaining red residue turning my new green coolant brown. It's mostly just re-sale value though. I wanna know what to do when it's time to sell these things, it will obviously be easier to sell them with clean, bright brass on the inside.

 

[Mr-Mechraven]

Where i work i clean brass/silver/gold/pewter and other metals almost everyday i will write a list of natural products you can use safely on brass. Make sure that it is solid brass and not brass plated though as treatment is different for both !!

Here's a few to try >

Fresh Squeezed Lemon Juice ( add salt as a natural abrasive, more salt more abrasion )

Cream of Tartar + Lemon juice ( a bit messy but works well )

Worcestershire Sauce

Yogurt ( yes yogurt the stuff you eat )

Or for tougher removal use ammonia ( usually 1 part ammonia to 8 parts water but you can make the solution stronger if you wish to ) * NOTE DO THIS IN A OPEN AND WELL VENTILATED AREA FUMES CAN CAUSE SERIOUS HEALTH ISSUES * Have to warn you about that

If you do choose to try ammonia then usually 10-15 minutes should do the trick , but you can leave for longer or change the solution to a stronger one.

Hopefully one of the above should help shift the staining, good luck !!

 

[DaaQ]

Or possibly, take it to a radiator shop and see if they have any advice on what will work or if they can do it.

 

[iamhollywood5]

Thanks Mechraven! Some good new ideas there, I'll probably try ammonia if nothing else works - I'm assuming there's no risk in damaging the radiator with that?

I just made a 1:1 water:vinegar mix, threw in 2 tbsp of salt, and heated it on the stove. Threw it in a makeshift loop and within seconds, it went from crystal clear to deep red. All that red would have eventually seeped out into the new coolant and made it brown. I'm shocked how much is still in these things after all I've done already. The loops is still running right now, hopefully when I empty it all out it will be clean as a whistle.

 

[Buzz247]

Quote:

Originally Posted by iamhollywood5

Thanks Mechraven! Some good new ideas there, I'll probably try ammonia if nothing else works - I'm assuming there's no risk in damaging the radiator with that?

I just made a 1:1 water:vinegar mix, threw in 2 tbsp of salt, and heated it on the stove. Threw it in a makeshift loop and within seconds, it went from crystal clear to deep red. All that red would have eventually seeped out into the new coolant and made it brown. I'm shocked how much is still in these things after all I've done already. The loops is still running right now, hopefully when I empty it all out it will be clean as a whistle.

Even if it looks good after that, I might suggest one more run of fresh brew to make sure everything is out. can't hurt, all it really costs is time

 

[iamhollywood5]

Quote:

Originally Posted by Buzz247

Even if it looks good after that, I might suggest one more run of fresh brew to make sure everything is out. can't hurt, all it really costs is time

I'm on the third brew now and it's still not clean =/ and this third brew is turning kinda pink. I'm done after this though, I've wasted enough time on it already and I don't have a good well-ventilated area to do ammonia, and I don't want to try anything that would ruin or reduce the effectiveness of the rad. If the new green coolant turns brown, I have tons more of it and I'll just drain and refill. Thanks for the help everyone!

 

[RX7-2nr]

I don't see what the problem is.