Need the strongest coolant flush for brown sludge in cooling system

To Ursatdx (post #7): What are those pie sections mounted on the wheels?

CTIS. Central Tire Inflation System. Adjust tire pressure on the fly. The pie sections protect the exposed valves.
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I use citric acid for wet tumbling of brass, and it does a wonderful job.

Honda has recommended CLR for clogged heater core rejuvenation.

Fleetguard Restore (alkaline) and Restore+ (acid) are cleaners intended to do things...
 
I use citric acid for wet tumbling of brass, and it does a wonderful job.

Honda has recommended CLR for clogged heater core rejuvenation.

Fleetguard Restore (alkaline) and Restore+ (acid) are cleaners intended to do things...
And greasy, oily residue can be cleaned with Cascade.

Gotta rinse and flush all these cleaners really well.
 
It's been a really long time since the car I have had a coolant system flush. It looks like the prior owner ran the wrong/cheap coolant. After many many water flushes it's still brown muddy water.

I'm even looking at potential DIY home recipes if anything like that exists for a cleaning. The car is 24 years old but still cools exceptionally well. I don't have to drive it everyday so even if there's something that works as an overnight thing even. I can do anything

Thanks in advance.
CLR Pro radiator flush and cleaner. I have 1 gal left over, if you near Bulverde, TX come and get it. Its scary good.
CLR Pro.webp
 
The Fleetguard Restore product I mentioned comes in two flavors. There's a PDF out there on it. Apparently alkali products are better on silicate gel. Acid products better for scale.

For instance, Prestone is a citric acid product but Motorcraft VC1 is alkali salt, according to the SDSs.

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First find out whats the “debris”

If its just rusty scale, citric acid at 10-15% will clean that up perfectly.

For best results, drain out the old liquid as much as you can, then just refill with the citric acid liquid and start it up, for 2-3 gallon systems with orange muck I run it for about 30-45 minutes and then let it cooldown, then just figure out how to push the acid out or drain it out.

E.g. on the chev 3800 motors the knock sensors are the drains, or you can remove one of the waterpump longer bolts and let it drain out. Then use a hose to push out any stale stuff sitting below that line, it less than a quart.

For some fwd 4 cyl fords you have to remove the thermostat (lowest point) or drain it hot so all the stuff in the head n block drains out. Rinse with boiling water through the heater bypass so it flows from the head to block and out the thermostat hole.

The rest can be pushed out with motive force of a garden waterhose. You can rinse out with some distilled or premix as a final step before buttoning it up and filling it up.

For v engine mercedes i just drain at the waterpump and radiator, for flushing that system (atf leak) I pinched the upper radiator hose shut while dumping the degas hose into a bucket while filling the system slowly with heated water, worked a treat to get all soap out. (Cascade)

Just use your imagination on how its plumbed and you will figure it out. Dont waste hundreds of gallons of distilled stuff to end up with a part flush.
 
I have a bucket with a bulkhead attachment on the bottom and it connects to a regular clear hose, shove that hose into a heater connection or make a junction connection yourself with a prestone T flush and some generic heater hose (dont cut your original one)

With the bucket on a ladder full of 5 gallons distilled and the system open for drain out, it will push out everything if you know what you are doing.

I used to use that to fill and burp some annoying cars too (now I use an airlift)
 
Anybody know the ratio (citric acid to water) to mix?
I'm guessing 2 c. per gallon water.

I bought a 10-pound bag.
I've used it to clean coffee makers/stainless steel thermoses and revived a home humidifier's wick with the stuff.

To Ursatdx (post #7): What are those pie sections mounted on the wheels?
FYI, here is a good write-up with photos on performing a citric acid cooling system flush on a Mercedes Benz diesel:

MB Citric Acid Cooling System Flush
 
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Zulf200 was the first to ask the germane question, what is the problem you're trying to fix?

Scale comes from lime in water, which isn't everywhere in the world, and reacts well to acid.

Oil comes from (former) head gasket/ ATF cooler problems and does well with detergent.

Remember BITOG gets mechanics from all over the place, with experience with their local water chemistry and resultant problems.

Rust comes from the iron block, and is a particulate so a filter will get it, but so also would a million drains and fills.

I would do the million drain & fills with tap water until the last couple of exchanges. Save samples as you work to assure yourself that you are actually having a positive effect over time.
 
Chemical flushes are awfully hard on water pump seals. Repeated water flushes are usually enough but that’s tough this time of year (freezing temperatures).
 
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