Cleaning Inside Radiator - Overclock.net

The Bartender Paradox · 12-29-06

I've got an old Volvo heatercore that I will be using inside my loop. It looks like it has been used long and hard. I ran some water through it and it came out white with small black chunks that look like styrofoam or some other plastickey insulator. I was thinking of washing it out with a bit of CLR mixed with distilled water, and was getting ready to do it, but I noticed on the bottle, among other things, it said not to use on copper. Thoughts? Should I use CLR, if not what else should I use?

Dryadsoul · 12-29-06

White vinegar and salt.

**ira-k** · 12-29-06

Put 10% white vinegar and 90% distilled water and shake the fire out of it...Let it sit over-night shake it a lot to...Thats how I clean new rad's don't know how well it will work on a corroded one....You might have to do that several times to ever get it clean if it even would...

I wonder how a little dilute Muriatic acid would do in it? I mean just a few % the rest distilled water...That might be worse then the CLR I don't know...If there is a Radiator shop near you they might be better able to tell you what to use....Tell them it's for Comp WC, that will get them laughing and may-be they will help....

....

The Bartender Paradox · 12-30-06

Thanks for the suggestions, I washed it out with water until the water coming out was clear last night. I just filled it about 1/3 up with white vinegar, shook the crap out of it for 20 minutes, and filled the rest up with distilled water. This is what it looked like. Left is water going in, right is water coming out. I will let it soak over night.

For the outside I have heard that soaking it in coke would clean it up. Ive got a ton of root beer, but no coke. Would that work?

hvacgaspiping · 12-30-06

Get a couple of bottles of radiator flush at an automotive shop. `Best to use a pump that will put out at or near the GPM that the water pump on the car accomplished. If that is not possible, use a pump that will allow heated water to go through it (do that anyway). I would use a 5 gallon bucket or even a larger container for a cleaning reservoir (maybe a 20 or 30 gallon trash can). Crank up your hot water heater to its hottest setting and let it get up to temperature, then draw water out of bathtub or a tap that will deliver the hottest water into containers you can carry outside (5 gallon buckets?) or wherever you intend to clean the radiator. Set the reservoir on something at a higher level than your pump and radiator. Attach the inlet side of the pump to a hose that will reach up and over the edge of the reservoir and then down to the bottom of the reservoir. Put a strainer with 1/8" mesh on the bottom end of that hose to keep the crud from recirculating through the pump. Attach a hose from the discharge end of the pump to the bottom opening of the radiator, and then attach a hose from the upper end of the radiator to dump into the reservoir. Once you have this setup and the pump circulating water, add the first bottle of radiator flush. Depending on how dirty the radiator is inside (hopefully not blocked up), it should take anywhere from 15 minutes to a half an hour of circulation to loosen most of the crud inside. Shut off the pump a couple of times during circulation and check the strainer to make sure it`s not filling up. If it is, pull it out of the reservoir and hose it clean, and then continue the flush. After you`re satisfied that the present cleaning has reached its maximum, stop the pump, dump the reservoir and radiator, and hose everything clean. Refill everything with cold water this time and recirculate again just long enough to see if the water gets dirty. If it does, repeat the above process with the hottest water you can get into it once again. After that`s done, get a strong light that is capable of putting light down inside of the radiatior, so you can see the tube ends which end vertically near the top of the radiator shell. If the radiator is clean these tubes should be completely clear. Look for a small white coating of lime scale on the inside of these tubes. This is the most difficult scale to remove. If it is still there, but mostly gone, repeat the flush. If it is heavy enough where you can`t see the copper internal wall of the tubes, then you will have to use a mild, INHIBITED, acid specifically made for lime scale. This should be used only as a last resort, because there is always a risk of a pinhole leak later on. If none of this works, then the radiator is not cleanable by inexpensive means, and may not be at all. Finally, don`t forget to set your hot water tank back to its normal temperature setting.

hvacgaspiping · 12-30-06

The pic you showed leads me to believe that there is lime scale present, even though you have cleaned it already (note the whitish color of the hose connection on the right). Circulation of hot water and whatever limescale cleaner you`re using is the best way to thoroughly clean a radiator. This will allow all internal surfaces to get the most benefit of the oxidizing properties of the cleaner. Shaking and letting it sit won`t be very thorough, and the remaining scale will just continue to grow. It`s a hassle, but worth it. If you`re using an acid on the internal portion of this radiator, make sure it is inhibited. Inhibitors stop the action of the acid from continuing to work when it is within the pores of the metal and can`t be rinsed. Using unhibited acid WILL cause leaks later; guaranteed. If you use an unhibited acid on the outside of the radiator, make sure it is not concentrated and rinse quickly and thoroughly.