What Are You Using to Flush Radiator?

[Dibbons]

My '96 Dodge Dakota is overdue for a radiator flush and fill. What's recommended these days? Thank you.

 

[toolmanmike]

I take the upperhose off at the radiator and stuff a garden hose in the radiator neck and flush it with hot water with the engine running.

 

[diesel_lv]

What color is the coolant, is it still running at normal temp? If it's still the original color and normal temp, complete drain and refill.

 

[zyzzyx]

I like to use a gallon of ZEP calcium and rust remover and a little bit of water to top it off,
run it with the cap off until it gets warm and then drain it and flush it with water. When you
refill the system, use distilled water and anti freeze.

 

[snakeoil24]

Cascade powdered dish machine detergent then neutralize with white vinegar

 

[YY1]

If it's rusty.....Thermocure.

 

[themechanic]

 

[bandit67]

On the V eight cars and trucks I do, I remove the lower block plugs and flush them out with a water hose nozzle . Some engines accumulate lots of sludge/crud down there that will not get flushed during a normal drain/flush/refill. Keeping that crud out of the radiator is worth the effort, IMHO

 

[diesel_lv]

Cascade powdered dish machine detergent then neutralize with white vinegar

Shouldn't that be the other way around? Vinegar is acidic and etched the metal, steel, aluminum, iron etc... and the Cascade pods neutralize the Vinegar to stop the etching.

 

[65wgn440]

This is what I use at the shop. Best that I have found.

 

[snakeoil24]

Shouldn't that be the other way around? Vinegar is acidic and etched the metal, steel, aluminum, iron etc... and the Cascade pods neutralize the Vinegar to stop the etching.

No Clean out Debris first with alkaline then metals are left for iron reduction. Simple rinse will deactivate the Vinegar quickly.

 

[Muddy Udders]

I'm currently doing a flush with oxalic acid (wood bleach powder). I tried blue devil with poor results. Supposedly there is no eating of the cast iron and no hydrogen embrittlement issues. After a couple hours I see a drastic improvement of water flow through the radiator.
I'm having overheating issues with this engine that sat for 30ish years.

 

[snakeoil24]

Oxalic Is perfect

 

[themechanic]

I'm currently doing a flush with oxalic acid (wood bleach powder). I tried blue devil with poor results. Supposedly there is no eating of the cast iron and no hydrogen embrittlement issues. After a couple hours I see a drastic improvement of water flow through the radiator.
I'm having overheating issues with this engine that sat for 30ish years.

Oxalic acid on Amazon 5 lbs for $22

OXALIC Acid 99.6% 5 Lb. Deck, Crystals, Metal Cleaning- Rust Removal, Wood Stain Remover and More!

OXALIC Acid 99.6% 5 Lb. Deck, Crystals, Metal Cleaning- Rust Removal, Wood Stain Remover and More! Amazon product ASIN B0147JPQAI
Can't paste the product page link due to the software update. @Joeychgo

 

[snakeoil24]

You should use 2%

 

[Muddy Udders]

Ouch I paid too much. But I figure if this works it's cheaper than a tear down and clean. After I put the grill and stuff back on it will get a test drive. Lots and lots of chunky stuff flushed out of it.

 

[themechanic]

Ouch I paid too much. But I figure if this works it's cheaper than a tear down and clean. After I put the grill and stuff back on it will get a test drive. Lots and lots of chunky stuff flushed out of it.

Probably should mix thoroughly with warm water before adding it to the radiator.

 

[Muddy Udders]

Absolutely, if not it would probably sink in and be a mess. I used three 12 Oz tubs for my system. 383 with 26" rad PH was in the 5's.