Cleaning out the radiator

ISPKI

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I really want to try the vinegar flush. I can get several gallons of that from restaurant supply depots for darn near nuthin, and its not damaging to the environment? Sign me up! I'll run 10 gallons of that thru my system no problem!

I wonder though, can you fill your system with straight vinegar and actually run the engine for a while to circulate it? Or would it be better to pump it in and thru your system? I was wondering if I could use a manual pump to push it thru and flush everything out. That drain petcock at the bottom of the radiator isnt going to allow any large particles to flush out of the system. I'm actually surprised it wasnt clogged...
 

gnathv

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I would take out the thermostat so it can fully circulate and run it for awhile. The vinegar should dissolve deposits. I would get some of the scale out of radiator and put in vinegar and see if it dissolves and how long it takes to dissolve before I started. White vinegar is 5% acid 95% water, cleaning vinegar is 6% acid 94% water. Cleaning vinegar is 20% stronger than white vinegar. To put it in perspective, coca-cola is more acidic than either.
 

Nugget

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Just to add my .02, in hopes it assists someone. Im in the process of rehabing my coolant system.

1. DO NOT put ospho into any closed vehicle system. Being a rust converter only, it is intended to dry per their instructions and outside the scope of the product.

2. The only acid I would ever put in the complete coolant system as a cleaner only, would be white vinegar. I did a 50/50 ratio and let it sit for 2 days after warming tge truck up. I left my thermostat in as i planned on replacing it.
I then drained out the vinegar solution and flushed with distilled water. Then filled the system with distilled water and warmed it up, then drained, then began disassembling.

3. Im doing the heater core separately, which is stated in the original service manual, and it states to back flush.
Im going to use non diluted clr in the heater core for 15 minutes, then flush with distilled water chased by blasts of compressed air. All the hoses are original so changing them all out.
 

BeastMaster

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Yeh, I was wondering about citric acid, phosphoric acid ( "Tile Smile " janitorial cleaner), or vinegar. I just got a ten pound bag of the citric off of Amazon, but that stuff ain't cheap. I'd like to boil my little crusties off too when I change out my coolant.

I'll probably use the citric.

Thanks to some previous posts here, the Phosphoric acid is no longer on the menu. A big thanks!
 
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Nugget

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I wanted to thank you for your inquiry as it sparked my deeper research into phosphoric acid revealing new information i never knew.

The concensus from my research, which was as clear as my old coolant, was phosphoric acid does chemically react with rust, but doesnt seem to convert if its not allowed to dry. It also, does not react with iron itself, so it doesnt eat the original material, which makes it pretty unique. And why its used to clean milking equipment on farms as it descales really well and considered food safe.
Phosphoric acid is a very effective rust remover, which is why i was a bit confused that it actually converts as well. So, it does do both.
And just for peoples knowledge, the other acid not commonly known for rust removal, yet very effective is oxalic acid and i would recommend searching machinist forums for rust removal.

And as mentioned, I need to research it more still to better understand it as I couldnt find many complete, simply written documents on it as if people were intentionally being vague, or simply didnt understand it well enough.

I would not use muratic acid for rust removal as it eats, well everything, demanding proper neutralizing, which is difficult to ensure. It is the best way to actually rust new metal quickly for that weathered look.
I have bought "milkstone" cleaner from tractor supply, which is 70% phosphoric acid, and was cheapish, its doubled since i last bought it, but so has everything. They did in store pickup, but dont keep it in stock.

To conclude, even though phosphoric acid IS the active ingredient in Ospho(which i just bought a gallon at Ace for $29), it has additives specifically designed with conversion of rust, not removal. Thats why i use the milkstone cleaner i linked too for aggressive rust removal, such as gas tanks. I wont use muratic anymore for even small stuff. Also to create a small bath to remove rust on bolts tools etc. I just pour it in an old glass pickle jar, so can use it repeatedly, which i need to do another for my base bath, and dissolving baking soda in boiling, or near, water allows for super-saturation as the solubility of baking soda to water is 8.9%, which increases with heating the water.

Hope that helps.


I have a mechanical engineering degree, which only means two things.
1. I have a perpetual, crack-like addiction, need to understand how everything works.
2. Im a pain in the @ss, due to # 1.
 

ISPKI

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I was a bit miffed on who was necroing a 2 year old thread but this is some interesting information.

So we are feeling that phosphoric acid is a good candidate for the coolant system?

I use a range of acids at work (Welding engineer) - Ranging from Muriatic toilet bowl cleaner (minimal strength) to Krolls etching acid (Hydroflouric, Nitric, + Catalyst at 90% concentration) that can turn a stainless steel aerospace component into a smoking pile of red sludge in a matter of minutes while also causing a localized evacuation of a metallurgy lab.

We do use Ox-Out extensively for eating away the oxide layer of aluminum to prep it for welding as well as removing the recast layer left from EDM manufacturer parts, usually also to prep it for welding. Ox-Out is a brand but they have a formulation for Iron and for copper alloys that should not eat the parent materials, problem is that its expensive stuff, ~240$ per gallon.
 

IDIBRONCO

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Sadly back in the "good'ol days" not long ago (10-15 yrs) I could pull my radiator off, carry to local radiator shop & get upper & lower tanks pulled & resoldered & core rodded & recored for $100-$150. Last yr I carried mine in & he wanted $1100 to recore it or sell me new brass core for $1200. sigh
Yep. They want everything to be disposable these days. Just like the new cars and trucks that are sold anymore.
 

Booyah45828

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I truthfully wouldn't use any acid in this scenario, unless you remove the heater core and radiator from the equation. Even a mild acid can cause electrolysis when in contact with dissimilar metals. There are too many available products out there for cleaning rust from cooling systems that don't harm radiators and heater cores that I'd be hesitant about using one that does.
 

Nugget

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Definitely, a No on using Phosphoric acid through the whole system or any strong acid, the seals especially, would object. As mentioned, removing the radiator or isolating the heater core separately, becomes a different story as i will explain just what i did with my heater in a moment. The theory of using ospho, aka phosphoric acid(i believe the concentration is about 30%) with water being the primary, to convert inside the system is a good thought, but not applicable for the whole system. Using in it a radiator removed, i havent evaluated enough to be confident with suggesting.

I might be buying our old 89 ford 1/2 ton fire truck with the trusty 4.9l and 5spd which has sat most of the time for decades and may be doing more experiments with flushing. When i think about being a redneck, i simply see it as applied engineering, which anyone can do. Even degreed engineers do dumb stuff that would bewilder a seasoned redneck, bc they often lack the common sense.
For example I offer, how long would it take a engineer to figure out which gas can his diesel is in vs his gasoline? We are so @nal we would short circuit. My redneck self, would simply smell it, with the "official" test being to just dip your finger in it, with gloves or not, and rub the together. The gasoline is considered a solvent, and like alcohol would evaporate quickly, its why it does not store well and its chemical deterioration over time, diesel is oil based and wont evaporate and has a natural lubricocity to it as you slip it between your fingers. So, people can stop judging rednecks for not having feelings, i feel my fuel plenty, so get that **** out of here, as im late for fishing.
Thought yall would appreciate that. FTR, i short -circuited when i confused my jugs, of fuel not on the wife, when it first happened, until I thought about it a bit over fishing, aka redneck meditation.


(I did not have a circulation pump, else would have used that for my heater core.)
The 89 Ford service manual specifically states to back flush separately when flushing the system.

With that said, the reason i used white vinegar through the system is because its a weak acid, and my 100 year old friends talked about it being the best way of removing rust from the bottom of the inside of my antique tea kettle. Just let it sit for a day or two. Apparently, some tea aficionados prefer a little rust flavor in their tea, go figure, i dont.

For my heater core, i back flushed while letting clr sit. I used an empty milk jug to catch it, used a funnel i squeezed into the 5/8 heater outer tube, held it up and poured. If you keep the inner heater hose up some it will aid in it sitting in there. Using this method, i actually switch directions, let it sit for 10 minutes and then with my compressor set to 40psi and not making too tight a seal blew it out. Using two milk jugs allows you to pour what came out back in while keeping most of the particulates in the jug. I put the jug low between the radiator and engine as i removed the alternator and vaccum pump.
I then flushed 6 times going both directions 3 times, alternating using a super-saturated mixture of baking soda, sodium bicarbonate, a base to thoroughly neutralize any acid in the clr left over. You will notice the chemical reaction as you pour it through and the bubbles coming out. I let it sit in there the first few times. (On hindsight, when flushing the entire system again, i would start with the vinegar, before using the base, where this time i did the base first through the whole system and warmed it up, also after draining the coolant originally, i would have used a heater core bypass kick before the base then vinegar flushes so that i wouldnt be bringing all the heater core crap into the system and it circulating back through the thermostat.)

I would not care about the coolant system this much if it wasnt for the criticalness to the operation of my motor. I knew none of this before this truck as its my first diesel.
Its no different than drinking sugary soft drinks, with phosphoric acid ironically, why going to the gym everyday. If that is all you drank, regardless of being in your early 20's and fit as a fiddle, you would suffer from kidney, renal, failure within a few months.

Now to finish painting my engine parts i removed, so my engine can compliment my redneck sophistication. Im using ospho on the rust and doing more redneck applied experiments.

PS never feel bad for reigniting old threads, because someone reading it after the fact doesnt know the difference. Sometimes it takes a few years of meditation, fishing, to discover some of the deeper existential redneck questions. I wouldnt necessarily ask someone directly in the thread from years ago, but you never know.

I may write all this up to put in the IDI Tech, as ive discussed it across several threads.
 
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