Prestone Radiator Flush

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grizzlygibbs

grizzlygibbs

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Has anyone used a radiator flush solution? I think my radiator has some sludge build up as I keep getting some very small amounts of gray residue up by my rad cap and in my reservoir. Anyway, I added this to my radiator that is partially drained since I am in the middle of my My overdue PM journey. Picture heavy. I dumped this crap in the radiator to hopefully clean it out and then will flush when I get things up and running. Anyone used or have good luck with this or a similar product?
 
Well? The Permatex brand says not safe on aluminum but the one does not. Is it any good, or just snake oil?

IMG_8466.webp
 
Thanks @NLXTACY, will prob do that by this summer anyway. Switching off from Toy red to Green rad fluid due to costs and availability and just wanted to get everything nice and clean. I will check in with results here and my pm thread.
 
For anything like that to work there has to be flow, if the tube is blocked there is no flow, experience dictates it is a waste of money, back flushing may help due to the pressure but, given a choice a new radiator is the answer, flushing out the heater rad as well while in there.

regards

Dave
 
blkprj80 said:
Nearly every time I used that crap in the past I've ended up losing a water pump in a month or so. Not saying that caused it, but had it happen 3 or 4 times. It was on gm vehicles that failed.
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Very possible, any crud gets loosened and fouls up the rubber seals of the pump, basically sanding them away.

regards

Dave
 
Good to know. I guess I will be buying a new water pump with my new radiator this summer :hillbilly:
 
Just drain and fill the radiator 4 or 5 times with distilled water driving around in between with full heat on front and rear. Then final fill full strength prestone universal in the radiator and reservoir. The left over clean distilled water in the system will dilute it down. I did this twice with 80's and according to my cheap coolant tester my protection level is -40 below.I used the lower radiator hose to drain, the plugs access is a bitch. Probably blasphemy here but my results have been good.
 
The last time I did a radiator flush I remember my petcock being really brittle too. So will likely use the lower hose. I do not believe my radiator is completely blocked but I do believe there is some sludge as I just cleaned out my reservoir last summer and have the gray silt on the bottom already. Will likely throw in a Koyo, before it gets too hot here.
 
Interesting, I read that the Permatex heavy duty was not safe for aluminum, but this product has no warning... Did you try contacting Prestone after your failure using this product???
 
I would only use water, knowing what I know. Other mud members here in my local club told me not to use any chemicals and I went ahead with my "But I am a certified scientist, I know better about organic and inorganic chemistry". Now I say "I am a mechanic, I changed my radiator". Both flushing and new radiator were easy jobs, but time consuming and for me time is worth a lot, can't recover time....
 
Bumping an old thread but i cannot fathom a product that goes into an engine that isn't compatible with aluminum? In this century? Let alone in the 90's. Even in the 80's aluminum was a common material in engines.

Prestone says this product is safe for all metals used in cooling systems.

I've never used it, but i have a bottle of it that i am planning on using real soon now, like when i can stand to be out in the heat.

The only product like this that I've used was liqui-moly's radiator cleaner. Used that in a '91 VW 1.8 yes with aluminum head and radiator. Worked GREAT. And i rinsed twice before i filled that engine with Pentosin G12+. That's been my sister's daily driver since december.

anyway, the instructions for this say you should run it for 10 minutes at temperature, then drain and rinse with another 10 minutes at temperature with straight water. I would wonder whether people who had issues with radiator flush products ran it for longer than that.

I don't have anything clogged, just a troubling quantity of rusty sediment in the green stuff i drained out.
 
Timpanogos Slim said:
Bumping an old thread but i cannot fathom a product that goes into an engine that isn't compatible with aluminum? In this century? Let alone in the 90's. Even in the 80's aluminum was a common material in engines.

Prestone says this product is safe for all metals used in cooling systems.

I've never used it, but i have a bottle of it that i am planning on using real soon now, like when i can stand to be out in the heat.

The only product like this that I've used was liqui-moly's radiator cleaner. Used that in a '91 VW 1.8 yes with aluminum head and radiator. Worked GREAT. And i rinsed twice before i filled that engine with Pentosin G12+. That's been my sister's daily driver since december.

anyway, the instructions for this say you should run it for 10 minutes at temperature, then drain and rinse with another 10 minutes at temperature with straight water. I would wonder whether people who had issues with radiator flush products ran it for longer than that.

I don't have anything clogged, just a troubling quantity of rusty sediment in the green stuff i drained out.
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Well I just used this stuff a couple weeks ago. I got my LC in May and best I can tell the coolant was last changed over 15 years ago if at all. My coolant was thick and brown. After a half dozen flushes with straight water I added a bottle of this stuff and drove normally for 2 days, probably 4-5 hours in total and then flushed the system again. What came out was pretty bad. Lots more sludge and some chunks of scale and crap. Flushed twice then ran straight water for 2 more days. Water was pretty clear after 2 days. Drained then filled with Prestone 50/50 Green.

Worked well for me. Not magic in a bottle but cleaned some and did no harm.

Edit: However as @NLXTACY said, if you are at the point of needing this a radiator replacement may be imminent anyway. I think mine most likely has permanent blockages that only replacement or rodding will fix.
 
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The Flush is mild citric acid like lime juice or a pop.
It is suppose to loosen any mineral deposits and they get flushed out.
Deposits do not always end up getting flushed out and sometimes cause harm.

Antifreeze contains buffers that balance PH to keep it from becoming acidic. This is why regular changes of the fluid will ensure it is not acidic even it solution appears good.

If you want to save some $$$ switch to green and change it every few years. It is easier than an oil change and old coolant can be flushed down the toilet or drain. Toyota Coolant systems will last a long time if cared for correctly.
 
Hornd said:
The Flush is mild citric acid like lime juice or a pop.
It is suppose to loosen any mineral deposits and they get flushed out.
Deposits do not always end up getting flushed out and sometimes cause harm.

Antifreeze contains buffers that balance PH to keep it from becoming acidic. This is why regular changes of the fluid will ensure it is not acidic even it solution appears good.

If you want to save some $$$ switch to green and change it every few years. It is easier than an oil change and old coolant can be flushed down the toilet or drain. Toyota Coolant systems will last a long time if cared for correctly.
Click to expand...

Sort of. The SDS says it's sodium citrate, which would be any of three different sodium salts of citric acid.

Probably trisodium citrate, since that's commonly used as a descaler. It is mildly basic.

The liqui-moly stuff is sulfonic acids, sodium salts, and surfactants (detergent).

The permatex heavy duty radiator flush is hydrochloric acid - wtf?! yes it's not compatible with aluminum.
 
Timpanogos Slim said:
Sort of. The SDS says it's sodium citrate, which would be any of three different sodium salts of citric acid.

Probably trisodium citrate, since that's commonly used as a descaler. It is mildly basic.

The liqui-moly stuff is sulfonic acids, sodium salts, and surfactants (detergent).

The permatex heavy duty radiator flush is hydrochloric acid - wtf?! yes it's not compatible with aluminum.
Click to expand...

I'm a little confused:

If H+ Ion Concentration is <7 it is an Acid
If H+ Ion Concentration is >7 it is a Base (Greater OH- Concentration).
 
Hornd said:
I'm a little confused:

If H+ Ion Concentration is <7 it is an Acid
If H+ Ion Concentration is >7 it is a Base (Greater OH- Concentration).
Click to expand...

Yep. Trisodium citrate in solution with water has a ph above 7.
 
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