MTFCA Forum

I have the radiator out of my '23 touring and thought it was a good time too clean/flush it out. Does anyone have any experience with products like Prestone Radiator Flush and Cleaner? Anyone aware of any downside? As always, Thank you for your thoughts.

I've had some *limited* successs with very badly clogged systems using such products. Be warned that if your radiator is in poor condition, using such products may cause it to leak. It may even leak like a shower head. Likewise, if your engine block/head has old repairs or rusted over cracks, there's a chance they will begin to leak. Personally, I'd start with a regular system flush with plain water. Then refill with your chosen coolant, run the car for a while and, if you have no overheating problems under normal operating conditions, you're done. PS: I believe that most cooling system cleaners depend on engine heat to work properly, and they're probably more effective in a system with a high temperature thermostat and a circulating pump.

10% pickling vinegar at full strength....

Coke, 12oz to About 1/2 liter. My best results included removing the radiator & reverse flushing from bottom outlet. I found much of the problem is rust flakes lodged in tube openings on top. If you drain the top tank & look carefully past the baffle you can see some of the tubes.

I've also had loose rust flakes plug the top of the tubes in several old cars. Removing the radiator and turning it upside down and flushing from the outlet would usually get most of them out. I'd have to do this over and over, and shake the radiator to help the loose flake find the filler and escape. Flushiing, then reverse flushing seemed to help You'll have to flush the block also, or more flakes will eventually find their way to the radiator and plug it again. I had a '59 Buick that had a bad overheating problem. You could run it until it was about to boil, then loosen the radiator cap and run for your life. It would erupt like Old Faithfull and blow most of the flakes out. After that, it would not overheat for a week or so, when more flakes would accumulate and plug it again. !!!WARNING!!!: Don't try this at home! It's a good way to get permanently blinded and disfigured!!

As far as OTC radiator flush products....a total waste of time.
Most are only a detergent and won't touch anything that will plug up a Model T radiator.
Years ago, there was a 2 part acid flush with a neutralizer, but that's been gone for 50 years.
But it worked !!
I agree with removing the radiator and backflush with a vinegar solution or CLR.

I think Dupont or K&N (K&W?) made the 2 part flush in a canister type package. It was pretty stout stuff. It might have been oxalic acid crystals.

Best radiator flush now seems to be a product from Evapo-Rust. If you've used their rust remover product you know how good that works and I've heard from several people that the radiator flush made by them works just as well. You can leave it in your system for an extended period without any problem.

My brother found a great price on ebay with free shipping. I run Green conventional antifreeze in my T so I don't have any rust buildup.

Dishwasher soap has to have very little suds activity.

I have been tempted to put one of those wash pellets in my radiator to see if they clean like they clean pots and pans.

I just got a couple of jugs of this Thermocure by Evapo-Rust in today. Each does 3 gallons. The '14 Touring has been getting better with each flushing but is still not done, there is rust in the block & probably in the radiator in areas that I can't reach so it will be worth trying this new radiator goo to see what I can do.

What is the cooling system capacity of the brass cars? How about the low steel? I tried to find the figure in the Ford book but didn't see it.

I used Evaporust bought at Harbor Freight in a gallon judge. I first learned about it on the 6.0 forum for my power stroke that was running some high temps. Worked like a charm actually ran it in the truck for several months before I flushed the coffee like contents out and then flushed till clear water came out. Drain it totally then filled with distilled water and antifreeze. Soaked a T head and block. Cleaned them really well. I didn’t try it while my T was running but will shortly. The best part of the end product of EvapoRust is that it is very environmentally friendly for humans and pets.

I have used vinegar to soak rusted vending machine panels and found it attacked the lead/puter lock parts and dissolved them if left in the solution too long. don't know about the solder joints in a radiator. but might not want to leave the solution in the radiator too long either. maybe someone has information about the effects of vinegar on lead.

A fellow T'er point out to me that i should have explained that coke has phosphoric acid as an ingredient. On a long club tour a fellow was having cooling issues. 1 or 2 cans used. Radiator cleaned itself as they drove on. No cooling problems for the rest of the trip.