DoubleDingo
Full Access Member
- Joined
- Jul 3, 2012
- Posts
- 11,254
- Reaction score
- 17,185
- Location
- Right where I am
- First Name
- Bagoomba
- Truck Year
- 1981
- Truck Model
- 81-C20 Silverado Camper Special-TH400-4.10s
- Engine Size
- Carb'ed Vortec 350
Can this be made into a Sticky?
I recently did some research on the subject, and performed the task myself, so I thought I would share with you all how I arrived at the positive results. I apologize in advance because I didn't take pictures of the process.
My truck is a 1981 Silverado Camper Special with 72,4** original miles. The radiator is the good brass type and besides it being corroded on the inside, and some stuff in the fins from a rat, it is in pristine condition. Some of you may not be so lucky, but I believe you can get similar results if you have a neglected cooling system like mine was.
Over Veterans Day Weekend 2013, I decided to buy 8 gallons of distilled water and 2 gallons of coolant. I normally buy Prestone, but this time I bought Peak because it was on sale. I don't research antifreeze but I have seen these brands pretty much all my life so they must be good quality or they would be out of business. So pick whatever antifreeze brand you prefer and go with that. I also bought some "Calcium, Lime, Rust" remover. I got the Zep brand because a whole gallon was about $14 dollars cheaper than a quart of the name brand CLR.
You will need plenty of containers, such as 5 gallon buckets, to capture the fluids to take to the recycle facility, or if you're lucky enough to have an enclosed sump at a shop, do the work there.
I began by draining the nasty looking brownish-grey coolant that was in the system. I drained and flushed the cooling system as soon as I got the truck in June 2012, but the coolant soon became the same ugly brownish-grey color is was when I first got the truck home. Even though the truck didn't overheat, knowing that crap was flowing through the engine and radiator didn't sit well with me. Then I pulled the thermostat, replaced the neck and upper hose on the intake manifold, and proceeded to flush the cooling system until I saw nothing but clear water coming out.
Next, I removed the radiator, used very sticky duct tape to plug hose inlets and outlet, and McGyver'ed up some duct tape plugs for the atf cooling ports, and used the cap to plug the cap opening. Before I covered up one of the hose holes, I poured a quart of the CLR in the radiator and topped off with water, and then capped with duct tape. When I removed the radiator from the truck I saw a bunch of stuff in the fins from a rat making a home between the radiator and AC condenser. While the CLR was working its magic inside the radiator, I shook the radiator from side to side to dislodge any scale on the inside of the tubes. I also used a blaster nozzle on the hose and set it to a low pressure from the hose bib so I didn't ruin the fins and I commenced to dislodging the debris I saw in the fins. I did this over the City-Issued green waste container because it has slots in the bottom and a lot of water was used. This is a tedious process but well worth the effort if you have plugged fins. I alternated between shaking the radiator from side to side, and cleaning the fins for a couple hours. Once I could see through the fins I found some screen and drained the radiator into a white plastic bucket. Amazing the amount of scale that the screen caught. I poured the clr mixture back in the radiator, and went back to cleaning the fins and shaking the radiator form side to side. Any bent or distorted fins I saw, I used a metal pick and gingerly reshaped them back to their original positions. Next, I removed any debris from the fins that I could grab with my fingertips. Lousy rat!
I was going to let the radiator sit overnight with the clr mixture in there, but I didn't want to chance ruining the radiator when all I was doing was trying to fix it. I didn't know for sure if the clr would cause a hole to develop, so to be on the safe-side I drained the mixture around sundown, which provided about 4 hours of cleaning time, and then I filled it with water, held one side up and listened for the water to evacuate one tank and fill the other. I did this over and over. Each time I drained the water, I opened up a duct tape plug to let it drain from that port. By the time I had all the ports opened up, the swooshing sound of the water going through the tubes told me they were clear. Yes, some scale remained on the ends of the tubes, but I could clearly see they were completely open.
So I put the radiator in my bathroom, and turned on the heater to dry it out really good.
While I removed the radiator from the truck, I also removed the coolant overflow tank so I could clean the inside of it too. I noticed two of the tabs were in bad condition and one was about to break off completely. I got out my Permatex Plastic Weld Epoxy, and basically applied it directly to the tank mixed it right on the surface of the tank and worked it into the plastic. There were two size-able cracks that got sealed up, the broken tabs were fixed up real good, and I reinforced the third tab for good measure. In the morning those tabs were stout and the mounting surfaces were ready to smoothed out by sanding them with a long board with rough sandpaper attached.
Since I was replacing the heads with vortec heads, I was able to rule out a blown head gasket causing the brownish-grey coolant in the neglected system.
I painted the radiator with some gloss black enamel, cooked it in the bathroom, and then let it sit in the sun once it warmed up enough to do so. With paint cured, and the engine back together, I reinstalled the radiator, thermostat, water neck and upper hose, coolant overflow tank, shroud, fan and fan clutch, and added some Prestone Super Flush, and topped of the system with water.
I ran this mix in the entire system for just under 4 days, and after going for a drive to get things nice and warm, I began the drain and fill process of the entire cooling system. At first the stuff coming out had chunks, and was the brown-grey color like before. I drained the system by removing the lower hose from the radiator. Each time I drained the system I filled with water from the hose, fired up the truck and let it run until the top hose was hot. Shut off the truck, drained the system, and repeated the drain/fill process until the water ran completely clear out of the system. At that point I didn't feel any guilt by letting the water drain on the ground. I started the truck and removed the outlet hose from the heater core where it attaches to the radiator, inserted a funnel in the radiator and poured 4 gallons of distilled water in the radiator with the truck running and clear water running out of the heater core outlet hose. When I got to the third 2-gallon container of distilled water, I turned off the truck, drained the system again, topped off with distilled water, ran the truck until the top hose was hot, shut off the truck, drained the system, and then ran the truck for about a minute with the hoses off so more water would come out.
The final step was to top off with straight coolant because of the water left in the block, and fill the coolant overflow tank with straight coolant up to the full mark.
After a week of driving, the coolant overflow tank only needed to be filled to full mark one time, and the coolant is a beautiful clear green color.
This sounds like a tedious process, and some of it is, but it is well worth it if you ask me. Next to receive this treatment is my other square, my 1991 Jeep Cherokee Laredo because after inspecting it, the replacement radiator I put in it about 8 years ago is brass! Sweet!!
I hope this helps some of you out there with neglected cooling systems, or those of you that want to clean the system right.
Edit: Had to rephrase some of the words because I kept getting interrupted.
I recently did some research on the subject, and performed the task myself, so I thought I would share with you all how I arrived at the positive results. I apologize in advance because I didn't take pictures of the process.
My truck is a 1981 Silverado Camper Special with 72,4** original miles. The radiator is the good brass type and besides it being corroded on the inside, and some stuff in the fins from a rat, it is in pristine condition. Some of you may not be so lucky, but I believe you can get similar results if you have a neglected cooling system like mine was.
Over Veterans Day Weekend 2013, I decided to buy 8 gallons of distilled water and 2 gallons of coolant. I normally buy Prestone, but this time I bought Peak because it was on sale. I don't research antifreeze but I have seen these brands pretty much all my life so they must be good quality or they would be out of business. So pick whatever antifreeze brand you prefer and go with that. I also bought some "Calcium, Lime, Rust" remover. I got the Zep brand because a whole gallon was about $14 dollars cheaper than a quart of the name brand CLR.
You will need plenty of containers, such as 5 gallon buckets, to capture the fluids to take to the recycle facility, or if you're lucky enough to have an enclosed sump at a shop, do the work there.
I began by draining the nasty looking brownish-grey coolant that was in the system. I drained and flushed the cooling system as soon as I got the truck in June 2012, but the coolant soon became the same ugly brownish-grey color is was when I first got the truck home. Even though the truck didn't overheat, knowing that crap was flowing through the engine and radiator didn't sit well with me. Then I pulled the thermostat, replaced the neck and upper hose on the intake manifold, and proceeded to flush the cooling system until I saw nothing but clear water coming out.
Next, I removed the radiator, used very sticky duct tape to plug hose inlets and outlet, and McGyver'ed up some duct tape plugs for the atf cooling ports, and used the cap to plug the cap opening. Before I covered up one of the hose holes, I poured a quart of the CLR in the radiator and topped off with water, and then capped with duct tape. When I removed the radiator from the truck I saw a bunch of stuff in the fins from a rat making a home between the radiator and AC condenser. While the CLR was working its magic inside the radiator, I shook the radiator from side to side to dislodge any scale on the inside of the tubes. I also used a blaster nozzle on the hose and set it to a low pressure from the hose bib so I didn't ruin the fins and I commenced to dislodging the debris I saw in the fins. I did this over the City-Issued green waste container because it has slots in the bottom and a lot of water was used. This is a tedious process but well worth the effort if you have plugged fins. I alternated between shaking the radiator from side to side, and cleaning the fins for a couple hours. Once I could see through the fins I found some screen and drained the radiator into a white plastic bucket. Amazing the amount of scale that the screen caught. I poured the clr mixture back in the radiator, and went back to cleaning the fins and shaking the radiator form side to side. Any bent or distorted fins I saw, I used a metal pick and gingerly reshaped them back to their original positions. Next, I removed any debris from the fins that I could grab with my fingertips. Lousy rat!
I was going to let the radiator sit overnight with the clr mixture in there, but I didn't want to chance ruining the radiator when all I was doing was trying to fix it. I didn't know for sure if the clr would cause a hole to develop, so to be on the safe-side I drained the mixture around sundown, which provided about 4 hours of cleaning time, and then I filled it with water, held one side up and listened for the water to evacuate one tank and fill the other. I did this over and over. Each time I drained the water, I opened up a duct tape plug to let it drain from that port. By the time I had all the ports opened up, the swooshing sound of the water going through the tubes told me they were clear. Yes, some scale remained on the ends of the tubes, but I could clearly see they were completely open.
So I put the radiator in my bathroom, and turned on the heater to dry it out really good.
While I removed the radiator from the truck, I also removed the coolant overflow tank so I could clean the inside of it too. I noticed two of the tabs were in bad condition and one was about to break off completely. I got out my Permatex Plastic Weld Epoxy, and basically applied it directly to the tank mixed it right on the surface of the tank and worked it into the plastic. There were two size-able cracks that got sealed up, the broken tabs were fixed up real good, and I reinforced the third tab for good measure. In the morning those tabs were stout and the mounting surfaces were ready to smoothed out by sanding them with a long board with rough sandpaper attached.
Since I was replacing the heads with vortec heads, I was able to rule out a blown head gasket causing the brownish-grey coolant in the neglected system.
I painted the radiator with some gloss black enamel, cooked it in the bathroom, and then let it sit in the sun once it warmed up enough to do so. With paint cured, and the engine back together, I reinstalled the radiator, thermostat, water neck and upper hose, coolant overflow tank, shroud, fan and fan clutch, and added some Prestone Super Flush, and topped of the system with water.
I ran this mix in the entire system for just under 4 days, and after going for a drive to get things nice and warm, I began the drain and fill process of the entire cooling system. At first the stuff coming out had chunks, and was the brown-grey color like before. I drained the system by removing the lower hose from the radiator. Each time I drained the system I filled with water from the hose, fired up the truck and let it run until the top hose was hot. Shut off the truck, drained the system, and repeated the drain/fill process until the water ran completely clear out of the system. At that point I didn't feel any guilt by letting the water drain on the ground. I started the truck and removed the outlet hose from the heater core where it attaches to the radiator, inserted a funnel in the radiator and poured 4 gallons of distilled water in the radiator with the truck running and clear water running out of the heater core outlet hose. When I got to the third 2-gallon container of distilled water, I turned off the truck, drained the system again, topped off with distilled water, ran the truck until the top hose was hot, shut off the truck, drained the system, and then ran the truck for about a minute with the hoses off so more water would come out.
The final step was to top off with straight coolant because of the water left in the block, and fill the coolant overflow tank with straight coolant up to the full mark.
After a week of driving, the coolant overflow tank only needed to be filled to full mark one time, and the coolant is a beautiful clear green color.
This sounds like a tedious process, and some of it is, but it is well worth it if you ask me. Next to receive this treatment is my other square, my 1991 Jeep Cherokee Laredo because after inspecting it, the replacement radiator I put in it about 8 years ago is brass! Sweet!!
I hope this helps some of you out there with neglected cooling systems, or those of you that want to clean the system right.
Edit: Had to rephrase some of the words because I kept getting interrupted.
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