Irontite Thoro-Flush Coolant System Cleaner - Removes Rust, Scale, Oil, Sludge & Gelled Dex-Cool - 16oz Powder - Cleans Cooling Systems, Restores Coolant Flow, Safe for Cast Iron, Aluminum & Plastic

This stuff ate the junk out of the radiator of the car next to me, it's that good. I have a VW Jetta Diesel that had a mystery water leak for quite a while. The PO dumped an asinine amount of 'stop-leak' into it, trying to fix it, to no avail. When I bought it, the system was so plugged up, the heater wouldn't work and the thermostat was glued open. I tore into it and found the leak, the water pump o-ring, under the timing cover. The vanes on the water pump were covered in goo, you could see caked up crap in the passages behind it. I thought I'd be hunting for a new car, but decided to give this stuff a try on the recommendation of a friend. Mind you, this system was so plugged up, it barely held a gallon of coolant, and the fans were running almost constantly. I went a step beyond the instructions, I replaced the thermostats, and flushed the system as best as I could with hose water, then drained it with a suction pump. I then filled it as the instructions recommended, and topped it off with distilled water. After the first 15 minutes, the recommended time, the heater started to work. I let it go 30 minutes, twice the time it said on the instructions. The water in the reservior looked like mud at this point and I was concerned about it eating the seals and gaskets in my engine. It took over an hour to completely flush the system after using this and get clear water running out of it, at first, there was goo coming out in clumps, it looked like river mud. After it cooled down, I again used the suction pump to be sure it was drained, used a scope to inspect the radiator, it looked like a new one inside, then I refilled it. It took the full gallon and a half of coolant to refill. It's been running fine ever since, the fans hardy ever come on, even with the A/C running.

Worked great but... If you have an older vehicle especially one with plastic on the sides of the radiator be prepared to be buying a new one. I was wanting to keep my 87 Ranger radiator because it was original and didn't leak at all. I knew the risk but went ahead with the flush. It worked really well. Follow the directions to the T. But the nearly 40yo radiator o-rings on the side tanks gave out. So I ordered a new aluminum one yay! It worked and I got a lot of crud out so I'd buy again.

A product that does what it says it does. Use on a Duramax Diesel with copper stop leak. Used the flush because I noticed the stop leak and noticed the color wasn’t all orange. It had a tinge of green. I was worried the mix would turn into sludge. Was thinking of using some other products but just didn’t think they would work. Then I came across this. One gallon dissolved most of the stop leak that was on the bottom of the exp tank. But some books and crannies still had some there. Used a second bottle and now the tank is clean. I’m going to assume if it cleaned the tank out, it also cleaned the water jackets, rad, and heater core. Some tips: Dissolve the powder in hot Tap water First. It will help dissolve all the crystals throughly. Then pour it into the rad or exp tank. You need to circulate this throughly through the system. Either drive or increase idle to bring the temp up enough to trigger the thermostat. Heat on full blast. Once it’s up to temp, then start the 12 minute timer. Then drain it. If you have a full dexcool failure, you have big chunks, it would be better to drain from a large hose rather than from a petcock. If possible, to create a lot of velocity in the system and really get stuff moving out, engine running, garden hose filling the system, drain the system at the same time. This turbulence generated by the water pressure and the circulation at the water pump will ensure most of the bits will get pulled out of the system. Then you can pull the hoses from the heater core and flush that out.

The product works well, the only downside, you will have to do a clean water flush several time to remove. Oh, and it does not taste that great either. I preformed the flush without removing the thermostat, and when the bottle states, do not run for more the 15 minutes, please be aware, it means a max of 15 minutes. At the 13 minute mark the vehicle started to heat up - quickly.

Amazed at what came out. I did a complete flush with no cleaner 2 week before and hardly any flakes or grit. This time I isolated the heater core and used a fountain pump, a bucket, garden hose fittings, and two 10 foot garden hoses to circulate the Irontite (half the bottle, gallon of hot water, and whatever anti-freeze in the core) for the 12 minutes. Then I flushed core with another garden hose with a shut-off valve to pulse the flow. I reversed the flow probably a dozen times before the water came out clear always keeping the drain hose in a bucket to see what came out. I have a 2009 Wrangler and finally have heat on my left side,150 degrees and my right side went from 100 to 170 degrees.

Flushed entire system thoroughly with a flush and fill kit before using several times. Ensured all hoses were clear and heater core wasn’t blocked. Installed new thermostat and ensured proper functioning. Added this flush properly and ran for 12 minutes. Once done there are still little white calcium rocks inside radiator. Maybe it’s supposed to chemically react with coolant, but doesn’t work well with straight water.

Had zero heat .. flushed the engine twice with another product. Flushed the heater core directly with this. BOOM. 160 degrees out of vents on an 18 degree day. Will use again.. saved me a 3 day job ripping out the dash to change the core

Works well. Follow directions closely. Their website says 10 mins run time in the direction video they have yet the bottle says 12 minutes. Be careful draining the hot coolant but the product works very well in my 25 year old jeep. Restored my heat from 90 at the vent to 135 degrees .

Worked great. I wish I used it on my other car before I replaced the heater core

I was dubious but needed to clean coolant system after two previous flushes dirtied after just a few days/ weeks. Used this and it did what I needed. Coolant system all clean - very satisfying. Expensive but when it works it is worth it

Based on several online reviews I attempted to use this product to unclog a heater core. Followed the directions to the letter and it did nothing. If you're buying this for a clogged heater core don't waste your money.

Worked beautifully!

I bought this as some reviewers on here and other internet forums have said that this removes 'stop leak' sealants from the coolant system. After using the product and following the instructions on the bottle, it made absolutely no difference at all. Total waste of money.