Cleaning rust/scale out of radiator, OUT of truck...?

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idahovette

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I think Chengny said to let it sit for a few hours and NOT circulate it. That may have caused the soapy reaction.
 

K5_489

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It was foaming _immediately_, as I was pouring it in. I dropped a gallon of water in first, then started pouring the Zep in. I didn't even get a quart of Zep in before I had foam pouring out of the fill hole. I started the pump at that point trying to get it to mix up hoping it would pull the foam down a bit.

But like I said, I started doing all this before I started reading all the replies too, lol.
 

Bigjake

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I wonder if you could use hoshizaki lime scale remover. I use it on my commercial ice machines and it gets the crap off the aluminum. Just a thought.
 

K5_489

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I wonder if you could use hoshizaki lime scale remover. I use it on my commercial ice machines and it gets the crap off the aluminum. Just a thought.

The what now?

I was actually thinking about this last night too, as the aluminum radiator that I pulled out of the K5 also has some rust in it, as the PO of the K5 also apparently preferred straight tap water to a antifreeze mix, and I know I definitely don't want to dump hydrochloric down that chute, lol.

I have zero intentions of ever putting that radiator back in the K5, but it would make for a handy radiator for the engine test stand...which I was also wishing I had made up as I was attempting to diagnose why the distributor wasn't producing spark last night, and thinking this would have been sooooo much easier to figure out with the engine on a stand rather than in the truck, lol.
 

Camar068

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wonder if diluting it with water first before pouring in would have helped? Seeing that picture makes me want to do mine in the spring.

I'll stop by and talk to the radiator shop that's fixed and later modded it to see if they clean them similarly.
 

K5_489

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wonder if diluting it with water first before pouring in would have helped?

NEVER NEVER NEVER add water to an acid, ALWAYS add acid to water.

Though the acid concentration in CLR type products is already low, it's still a good habit to be in. Reason being that adding water to an acid causes a chemical reaction that creates heat. On higher acid concentrations, this can be enough heat to immediately cause the water to boil, and thereby cause the acid to splash back up at you.

Going the other way, acid to water, means that the volume of water is usually enough to absorb the heat of the reaction without significantly raising the temperature of the water.

Plus, there was already a gallon of water down in the radiator, so it was getting diluted already :p
 

Tonyg123

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I usually pull the rad and add vinegar / water solution. Let lay overnight and wash with clean water the next day. Youll be surprise what will come out
 

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