Has anybody cleaned their radiator with CLR ?

[MountainGoat1966]

The copper/brass radiator in my 84 is due for a good cleaning, the tubes flow very little coolant.
I can't afford to replace it, and having a radiator shop do a cleaning job would require two 130 mile round trips, since it'll most likely be the next day or so after I drop it off until it's ready.
Plus the cost of the shop to rod out a three row radiator.
I'm tempted to make a cap to close off the hose connections, get three or four jugs of CLR, and clean it off the truck.
I'm not sure about running the stuff through my engine block, even though there is nothing aluminum in it, so I won't do it while still installed.

[81GMCSierra1500]

Originally Posted by MountainGoat1966

The copper/brass radiator in my 84 is due for a good cleaning, the tubes flow very little coolant.
I can't afford to replace it, and having a radiator shop do a cleaning job would require two 130 mile round trips, since it'll most likely be the next day or so after I drop it off until it's ready.
Plus the cost of the shop to rod out a three row radiator.
I'm tempted to make a cap to close off the hose connections, get three or four jugs of CLR, and clean it off the truck.
I'm not sure about running the stuff through my engine block, even though there is nothing aluminum in it, so I won't do it while still installed.

I couldn't see any problems arising from this, as CLR is not corrosive. Just find a way to get it constantly running through the rad, so as not to leave excess. And make sure you give a good rinse with fresh water afterwards. But I wouldn't think it would be problematic.

[hatzie]

CLR used to contain phosphoric acid and Citric Acid. Not sure what it contains now that it's "Phosphate free" but I bet it's still a mild acid.

Back in the dark ages I flushed several mildly abused cooling systems on my father's vans with an acid type product that had two parts. A Flush and a neutralizer.
It worked very well;

• Drain the brown murky stuff and heave it
• Thoroughly rinse the system with a garden hose
• Mix up #1 with warm tapwater till it all dissolves then pour in and fill up with the hose
• Put on the old cap and run engine up to temp then cool down to warm
• Thoroughly back and forward flush with the garden hose
• Mix #2 with warm tapwater til it all dissolves, pour in and fill with hose.
• Put on the old cap and run engine up to temp again then cool down to warm
• Thoroughly back and forward flush with the garden hose again
• Put on a new thermostat
• Replace any dodgy hoses and clamps
• Replace the leaky radiator and-or heater core you just discovered... If you weren't lucky and they leaked.
• Fill with 50:50 Anti-freeze and distilled water
• Install the new radiator cap and run her up to temp to check for any leaks...

That flush was probably Tri-Sodium-Phosphate or some equally nasty stuff. It cleaned out all of the lime crud and even rust right down to the raw iron, copper, steel, and aluminum. The plastic overflow tanks became translucent again instead of brown.
If I had had any leaks they would've become gysers, or at least very real leaks, so be prepared to discover nasty things. I never had the scale or rust come back in 75K on either van.

I'd go for it. Be very sure you have every drop thoroughly rinsed from the cooling system. Be sure to rinse it off the body and frame when you're done too. Maybe even go so far as to neutralize it with a pre-mixed baking soda and water solution poured in and filled with tap water then run up to temp again... then rinse that crap out and fill with your favorite poison.

[69chevytrucker]

drain rad then put in couple jugs of vinegar add some water run it for a cycle or two just leave it in there for a day or two run it again for a bit wash it out and should be clean

[bdiamond]

I used ice machine cleaner in mine. It is citric acid. It got a ton of rust out of it. I was planning on replacing the radiator anyway just wanted to get it running first. The radiator appeared to have only had water in it for a long time and was empty when I got it. Shortly after the trans cooler section ruptured.....I get to replace the transmission now too.

[MountainGoat1966]

I removed the radiator today and set it flat on a board.
There was no rusty crud as I am pretty good at maintaining the coolant mix.
The CLR I had seems to have sprouted legs and disappeared, so I went to plan B which was a gallon of white vinegar.
Plan C would have been a 50/50 mix of muriatic acid and water.
Let it soak for about an hour, then rocked the radiator back and forth a few times to work the vinegar through the tubes.
I did notice an increase in how fast the liquid moved through the tubes and some white and green crud did come out..
Did a good flush, then flushed with baking soda water, then fresh water flush twice.
After reassembling the truck, I did notice the coolant flow is better, but still not what it should be.
Most of the radiator tubes only have a trickle with the engine running as I shine a light down through the filler neck.
A few tubes now shoot a stream of coolant where they didn't before.
I guess I need to get some CLR and do it again.
I gotta get this engine down to a reasonable operating temperature.

[farmall]

SECTION 3 - COMPOSITION /INFORMATION ON INGREDIENTS
Component CAS# OSHA HAZARD % by Weight
1. Lactic Acid 79-33-4 YES 12.00-18.00
2. Gluconic Acid 526-95-4 YES 2.50-3.75
3. Lauramine Oxide 1643-20-5 YES 1.50-3.25

I would run it through the whole system. It cant be as potent as the DuPont 2 part cleaner. Then as suggested rinse with soda.

[parrisc19844x4_468]

I just did it to my 83 this weekend. It was running about 210F and I thought that was too high.

1. Drained the who system, disconnect the lower rad hose from eng block. Removed drian plug from Rad. Drained the overflow container.
2. Rensied Rad with graden hose.
3. Disconnecd heater hose to the Rad. Remove the upper rad hose. Capped off the lower and upper Rad hose so vinegar wont leak out. Plug the nipple to heater hose. Filled Rad with distilled vinegar. Let it set for 4 hours.
4. Drain the Rad. Rensie for about 5 mins with garden hose.
5. Reconnect all hoses(replace if needed), Replaced the thermostat.
6. Fill rad with garden hose water. Run truck for about 5 mins. Let it cool down, drain water. Pain, but I disconnected the ower hose again and lossened the drain plug on the Rad.
7. Connect lower hose and tighen drain plug.
8. I filled mine with the 50/50 anitfreeze from Peak. The water they use is distalled. You should not use garden hose water for your mixture if you buy the 100% anitfreeze. Spend a few bucks and buy some distalled water. Your graden hose water has too many hardners in it and will eventually get you back to the reason we are doing this now.

Results. My temp went down to just blow 200F after a vigrours Sunday afternoon workout.

[hatzie]

Run the engine up to temp with the flush inside the whole system not just the radiator.

If the heater or water pump fails they were on the way out already.

My trucks run right around 185 most of the time.

[Skunksmash]

Originally Posted by hatzie

CLR used to contain phosphoric acid and Citric Acid. Not sure what it contains now that it's "Phosphate free" but I bet it's still a mild acid.

I'm curious about the acid. It seems to me, that any acid wouldn't matter because it simply wouldn't be there long enough. Or would it? It seems like it would just be flushed back out or neutralized when you finally thoroughly flushed the radiator again, with the garden hose.

[parrisc19844x4_468]

Ok, guys check this out. I wan't satisfied with just under 200, so I put my temp meter on it after just idleing for just a few mins, my meter is showing 158 to 159. The OEM guage was reading just under 200. To check my meter i let it sit in the shade and it is showing 66, which is our temp here today in Wisconsin. I would like to belive my meter but 158 seems low. Thoughts?

[parrisc19844x4_468]

Originally Posted by hatzie

Run the engine up to temp with the flush inside the whole system not just the radiator.

If the heater or water pump fails they were on the way out already.

My trucks run right around 185 most of the time.

Read step6.

[hatzie]

Didn't you drain the vinegar solution in step 4...? That means step 6 is just water...

I was recommending that your flush chemical of choice be run to temp in the whole system. It'll clear the hard water deposits from the block and head passages as well as the heater core. The heat will accelerate the chemical reaction between the acid and the hard water deposits.

158F seems a little low for full operating temp on the block unless you are running a 165degree thermostat. Once she is up to temp the block should hang right around the thermostat opening temp maybe varying by +/-5 degrees F or so. The thermostat should open and close to regulate coolant to the radiator. Mine climbs pretty fast to about 210 and then drops back to 170. Then it climbs back to 185-190 and stays there pretty steady (two 185 degree F thermostats). The 6.x Diesel engines are not noted for excellent cooling but mine seem to hang right where they should.

[71swb4x4]

Originally Posted by parrisc19844x4_468

Attachment 1299378

Attachment 1299379

Ok, guys check this out. I wan't satisfied with just under 200, so I put my temp meter on it after just idleing for just a few mins, my meter is showing 158 to 159. The OEM guage was reading just under 200. To check my meter i let it sit in the shade and it is showing 66, which is our temp here today in Wisconsin. I would like to belive my meter but 158 seems low. Thoughts?

What are you reading the temperature of? It looks like you are reading the temp of the outside of the sending unit. It's tough to tell in the pictures though.

[parrisc19844x4_468]

Originally Posted by hatzie

Didn't you drain the vinegar solution in step 4...? That means step 6 is just water...

I was recommending that your flush chemical of choice be run to temp in the whole system. It'll clear the hard water deposits from the block and head passages as well as the heater core. The heat will accelerate the chemical reaction between the acid and the hard water deposits.

158F seems a little low for full operating temp on the block unless you are running a 165degree thermostat. Once she is up to temp the block should hang right around the thermostat opening temp maybe varying by +/-5 degrees F or so. The thermostat should open and close to regulate coolant to the radiator. Mine climbs pretty fast to about 210 and then drops back to 170. Then it climbs back to 185-190 and stays there pretty steady (two 185 degree F thermostats). The 6.x Diesel engines are not noted for excellent cooling but mine seem to hang right where they should.

Yes I did drain the vg. I guess my thought was I didnt want those chemicals in my block. The eng was recently rebuild and heads were boiled out and checked.

good to know about where the temp should be normal. I have a 180 thermostat, so yea was wondering why it was so low and the other thing is my oem gauage in the truck was way off.

I hooked my mutilmeter temp guage to the same place where the OEM guage wire is connected right on the water temp sensor. Would this be a good test?
Seems so.

[KQQL IT]

Used Tide powder detergent in one mucked up with rust and Dex cool.

[parrisc19844x4_468]

Originally Posted by 71swb4x4

What are you reading the temperature of? It looks like you are reading the temp of the outside of the sending unit. It's tough to tell in the pictures though.

I hooked the wire from my mutimeter to the water sensor plug, same place where the OEM guage is connected to.

[hatzie]

Are you running a 160 degree thermostat?
Do you trust your thermocouple?
It might be time to change the thermostat...

[71swb4x4]

Originally Posted by parrisc19844x4_468

I hooked the wire from my mutimeter to the water sensor plug, same place where the OEM guage is connected to.

Attachment 1300177

I am not sure you are accurately testing at the sending unit. The sending unit is limiting voltage with a spring, as the engine gets warmer the spring is decreasing resistance. Is that resistance what you are measuring with your multimeter?

[parrisc19844x4_468]

Originally Posted by 71swb4x4

I am not sure you are accurately testing at the sending unit. The sending unit is limiting voltage with a spring, as the engine gets warmer the spring is decreasing resistance. Is that resistance what you are measuring with your multimeter?

No I am measureing the temp. My multimer has a seting for temp and a special temp wire. But I see your point. Maybe the temp is disapated by the time it reaches the outside of the sensor.

Where would be a good place to take the actual temp? I dont want to open the system as it is under pressure.