What liquid can I soak radiator in

oldford

Senior Member
Since I have the radiator out of car I would like to soak it in an old plastic kids pool I have. There is not any rust that I can detect just dirt and gime from over 90 years of use. I know about the products to put in radiator when running car but is there something I can use now since I can completely cover it with water, thanks
 
I've used A/C condenser foam spray cleaner on radiators before and it worked really well. Should work even better since you have it out and are able to get to both sides easily.
 
Are you looking for "exterior" or "interior" cleaning (i.e. "Boil out.")

Assuming copper/soldered radiator with tubes/fins. And not one of those blasted "honeycomb."

Joe K
 
Mostly exterior but if it goes into the tubes that's OK. It's an original radiator with tubes and fins.
 
Spray it down with straight Simple Green, lay it flat in a large plastic trash bag and seal the bag up with as little air as you can. Allow it to "soak" for a day or so and reapply more Simple Green. Repeat until things are softened up and then spray it off with a garden hose. To clean grease and gunk out of the inside of the radiator seal the end of the lower pipe and over flow tube and then pour straight Simple Green in the radiator and put the radiator cap back on. Invert the radiator several times over the next few days. Drain and rinse.
Cleaned my original radiator up nicely. Runs very cool.
 
Go to a hardware store and get septic tank cleaner crystals. Mix it with water. That's what a radiator shop uses except theirs is hot. Caustic soda is what I was trying to remember. An OLD GOOD hardware store will have it.
 
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Since I have the radiator out of car I would like to soak it in an old plastic kids pool I have. There is not any rust that I can detect just dirt and gime from over 90 years of use. I know about the products to put in radiator when running car but is there something I can use now since I can completely cover it with water, thanks

While the radiator is out of the car, take it to an old fashioned radiator shop (if you can find one within a reasonable distance from you) and have them clean it for you.

They take the tanks off, they boil the core, they rod out each tube (literally run a metal rod that matches the ID of tubes down through each tube), and then they solder the tanks back on for you. Around here it costs about $100.

It is hard to get a solvent or a cleaner to get into a plugged tube because the tube is plugged.

Good luck.
 
While the radiator is out of the car, take it to an old fashioned radiator shop (if you can find one within a reasonable distance from you) and have them clean it for you.

They take the tanks off, they boil the core, they rod out each tube (literally run a metal rod that matches the ID of tubes down through each tube), and then they solder the tanks back on for you. Around here it costs about $100.

It is hard to get a solvent or a cleaner to get into a plugged tube because the tube is plugged.

Good luck.
$100 for rodding out a radiator? Day-yum, I'd jump all over that. Last one I had done was about 5 years ago and it was $260. I don't know what it would be now, if I can even find a shop that knows how to work on brass radiators. Of course, our shop rates here in the Bay Area hover around $150/hr.
 
$100 for rodding out a radiator? Day-yum, I'd jump all over that. Last one I had done was about 5 years ago and it was $260. I don't know what it would be now, if I can even find a shop that knows how to work on brass radiators. Of course, our shop rates here in the Bay Area hover around $150/hr.

That's because I live in a low cost rural area, you live in higher cost SF.

And my mountain views are excellent! :D
 
The radiator shop cleaning is absolutely the best approach, but if you decide to tackle this job yourself cap off the upper and lower water outlets and pour in a mixture of 75% phosphoric acid and 25% water until it is full. The phosphoric will not harm the metal of the upper and lower tanks nor the tubes but it will dissolve rust, water scale, and a lot of the crud that settled into the bottom tank over the years. Let it sit upright for at least a day and then flush well. The phosphoric acid will do a good job of amateur cleaning at a reasonable expense. This process has worked very well for me numerous times without a problem.
 
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