1972 C10
- Thread starter sprint_9
- Start date
Klleetrucking
Promoted Users
Super Bummer!
Chris_Hamilton
Trying to be the best me, I can be
Sprint....buck up my man! 
You've put too much time, effort, and money to give up on this beauty.
Here is a thread over at The HAMB that covers this topic. Go to post 14 for correct way to do it. The commercial stuff available today isn't all that effective. You don't need to drive it, just start it, get it warm, and let it sit. Come back a few hours later and do the same thing. Continue for a couple of days. Then flush it. May need to flush it more than once.
Would also be a good idea to pull the radiator before and after and flush it out to be sure that it is not plugged up and to get the crud that the acid treatment loosens up out as well,
It will all eventually come out, just gotta use the right technique and be a little persistent. Use distilled water as well. Both when doing this and when you refill afterwards. You can do this.
www.jalopyjournal.com
You've put too much time, effort, and money to give up on this beauty.Here is a thread over at The HAMB that covers this topic. Go to post 14 for correct way to do it. The commercial stuff available today isn't all that effective. You don't need to drive it, just start it, get it warm, and let it sit. Come back a few hours later and do the same thing. Continue for a couple of days. Then flush it. May need to flush it more than once.
Would also be a good idea to pull the radiator before and after and flush it out to be sure that it is not plugged up and to get the crud that the acid treatment loosens up out as well,
It will all eventually come out, just gotta use the right technique and be a little persistent. Use distilled water as well. Both when doing this and when you refill afterwards. You can do this.
Technical - Best way to de-rust cooling system?
Whats the best way to clean out the cooling system in a 1950 cad? Ive hosed it out several times, but it still runs hot, and the coolant eventually...
www.jalopyjournal.com
Vanillagorilla
Professional amatuer
A friend of mine uses powdered Cascade to clean coolant systems. A old timer at a diesel shop he worked at swore by it. He tried it and now he does it all the time. Worth a try
I like the ideas suggested; I never had the problem, so I dont know.
I assume while a flush, the thermostat is out?
If none of this works would it not be cheaper to take the engine apart and send it to a machine shop for cleaning only with the heads than assemble it?
.aybe a machine shop could clean with the engine together; I dont know how they clean blocks, just a thought. And id run it by a couple and see what they say.
Of course, a new LS9 would work great in that truck. Lol
I assume while a flush, the thermostat is out?
If none of this works would it not be cheaper to take the engine apart and send it to a machine shop for cleaning only with the heads than assemble it?
.aybe a machine shop could clean with the engine together; I dont know how they clean blocks, just a thought. And id run it by a couple and see what they say.
Of course, a new LS9 would work great in that truck. Lol
RosharonRooster
Promoted Users
The truck is totally worth repairing it. Don't give up. It's just nuts, bolts, and time.
Chris_Hamilton
Trying to be the best me, I can be
Pros use sulphamic acid for hard water, lime and antifreeze build up. Oxalic acid to remove the rust. The stuff they sell now is not as effective as the two acids I mentioned. They are still commonly available though. Sulphamic acid is usually marketed as grout and tile cleaner. Oxalic acid is known as "wood bleach" The link I shared above goes into detail on it and how to mix the acids properly. It will be the most effective way to clean it. Muriatic acid is often used on bare blocks but it wouldn't be ideal for an installed running engine.
Pantyhose on the return line would be a good way to filter the crud.
For a machine shop to clean it, it would need to be totally disassembled. They use a caustic soda and hot water solution and it's not viable for assembled engines.
Sulphamic acid example: https://www.custombuildingproducts.com/products/tilelab-sulfamic-acid-cleaner-2
Wood bleach example: https://www.realmilkpaint.com/shop/strippers-removers/oxalic-acid-wood-bleach/
Pantyhose on the return line would be a good way to filter the crud.
For a machine shop to clean it, it would need to be totally disassembled. They use a caustic soda and hot water solution and it's not viable for assembled engines.
Sulphamic acid example: https://www.custombuildingproducts.com/products/tilelab-sulfamic-acid-cleaner-2
Wood bleach example: https://www.realmilkpaint.com/shop/strippers-removers/oxalic-acid-wood-bleach/
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sprint_9
Rookie
Thanks everyone for the replies and ideas. It is nice to get different perspectives.
Ive considered just removing the screen and letting it go, but I have a brand new Dewitts radiator Id really like to install and not ruin.
Yes I had Thermocure in it at one point for a couple days. After that regular Evaporust for a week. After all that I flushed with block plugs out, and flushed with it for probably a total of 4 hours with the engine running, revving it trying to work the debris out.
Combustion gasses is not a bad thought, but I don't think this is the cause. I have some old pictures of the motor with the heads off and it shows how bad things really were. It was just one of those things that was overlooked as I wasn't really even considering this issue.
I altered the original thermostat so that it is just the outer housing with no spring or valve, allowing full flow constantly for flushing.
The rest are good suggestions that I will look into further and try. Ive experimented soaking some saved debris to see if I can find something I can dissolve it with but haven't tried some of the things mentioned. Im somewhat confident I have the block itself fairly free of rust as I have looked up into the hole for my one of the block drain plugs. I think the problem I have now is the sheer amount of debris I have removed from the block that is now stuck in the block running through the coolant system like a sand blaster. Ive gotten a lot of debris out already I feel like, but Im thinking there is a lot more to come out based on some of the things Ive seen with it. With all the debris that appears to be trapped my throw in the towel decision last summer was to pull it to clean or replace the block.
Ive considered just removing the screen and letting it go, but I have a brand new Dewitts radiator Id really like to install and not ruin.
Yes I had Thermocure in it at one point for a couple days. After that regular Evaporust for a week. After all that I flushed with block plugs out, and flushed with it for probably a total of 4 hours with the engine running, revving it trying to work the debris out.
Combustion gasses is not a bad thought, but I don't think this is the cause. I have some old pictures of the motor with the heads off and it shows how bad things really were. It was just one of those things that was overlooked as I wasn't really even considering this issue.
I altered the original thermostat so that it is just the outer housing with no spring or valve, allowing full flow constantly for flushing.
The rest are good suggestions that I will look into further and try. Ive experimented soaking some saved debris to see if I can find something I can dissolve it with but haven't tried some of the things mentioned. Im somewhat confident I have the block itself fairly free of rust as I have looked up into the hole for my one of the block drain plugs. I think the problem I have now is the sheer amount of debris I have removed from the block that is now stuck in the block running through the coolant system like a sand blaster. Ive gotten a lot of debris out already I feel like, but Im thinking there is a lot more to come out based on some of the things Ive seen with it. With all the debris that appears to be trapped my throw in the towel decision last summer was to pull it to clean or replace the block.
Chris_Hamilton
Trying to be the best me, I can be
Sprint do what I suggested. It will be the least amount of labor and it will work. Done it many times on old cruddy stuff. The acids I mentioned will get rid of the scale and rust.
sprint_9
Rookie
Will do Chirs, Im going to give some of those ideas a shot for sure in the spring. Reading over some of your guys suggestions has given me some new ideas of my own to try as well.
Id really like to just save this dumb thing and not deal with a major project. Sure it would be kind of cool to rebuild it as my own, but you start adding up expenses at the machine shop, basic rebuild supplies, and any other extra go fast parts and things get out of hand quick. Then I look at how much I already have in it and how things have gone with it and it really just turned me off. Rebuilding this engine into a real beast is something I wouldn't mind doing down the road 10 years, not after 2 years and about a 1000 miles.
I agree, Ive learned a lot from him, as well as many others on here.
Chris_Hamilton
Trying to be the best me, I can be
Oxalic acid is one that doesn't attack base metal. Or so I've heard.
My advice is to contact an industrial radiator service that focus on larger diesel engines and seek their advice before tearing the engine down. Farm (ag), mining, refinery/chemical plant, and marine country usually yield pretty experienced folks who have seen just about all the kinds of corrosion/precipitate issues before on internal combustion engine cooling systems. If you live in Iowa, dissolved solids water chemistry could be a factor if someone before you had issues with build-up inside the old engine. Saw that in Wyoming in less than six months in operation and no water treatment/ inhibitors/etc.......Something might be new to you or me--but there is someone who is a corrosion specialist that has seen your problem before in their occupation. You might find a good automotive one too-but in my experience many just want to sell you a new item etc. It just depends on where you live.
If you can put normal antifreeze back in the system and run it--try to find some place to do a PH test on the coolant and sludge that comes out. That's going to tell you what Crashtech mentioned. His idea is spot on.
You might want to put the problem out on one of the engineering internet forum boards dealing with corrosion over the winter. It is a trillion dollar problem per year for the USA alone. Likely, one of those folks has seen or been involved in what you are experiencing. The Southeast USA is full of the best in the entire world and the brightest ones for these problems.
People talk about acids and what they are used for, and no one mentions molarity. What's that? How much "acid" (hydronium ion) is in solution. That's where a person can get into real trouble fast and with devastating health consequences attempting to clean something. Seen it once. I do not recommend automotive enthusiasts use industrial strength acids and such things unless competent chemist advice is sought or marketed products are used. What's too potent? That depends on where you buy such things and how comfortable you are around potentially being hurt badly. People complain about professional strength for commercial use marketed products today being "weak now" well there's a reason for that. Sometimes it's deaths or gruesome disfigurement. I've used "hot and nasty strength" nitric, hydrochloric acids, and some potent caustics in my occupation with exhaust hood ventilation etc. from time to time to do metal sample etching and now I have stopped. "Went over the hill", so to speak, and don't feel right anymore doing what I once did.
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If you can put normal antifreeze back in the system and run it--try to find some place to do a PH test on the coolant and sludge that comes out. That's going to tell you what Crashtech mentioned. His idea is spot on.
You might want to put the problem out on one of the engineering internet forum boards dealing with corrosion over the winter. It is a trillion dollar problem per year for the USA alone. Likely, one of those folks has seen or been involved in what you are experiencing. The Southeast USA is full of the best in the entire world and the brightest ones for these problems.
People talk about acids and what they are used for, and no one mentions molarity. What's that? How much "acid" (hydronium ion) is in solution. That's where a person can get into real trouble fast and with devastating health consequences attempting to clean something. Seen it once. I do not recommend automotive enthusiasts use industrial strength acids and such things unless competent chemist advice is sought or marketed products are used. What's too potent? That depends on where you buy such things and how comfortable you are around potentially being hurt badly. People complain about professional strength for commercial use marketed products today being "weak now" well there's a reason for that. Sometimes it's deaths or gruesome disfigurement. I've used "hot and nasty strength" nitric, hydrochloric acids, and some potent caustics in my occupation with exhaust hood ventilation etc. from time to time to do metal sample etching and now I have stopped. "Went over the hill", so to speak, and don't feel right anymore doing what I once did.
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MDPotter
Promoted Users
Sorry to hear about these problems and your frustrations. I'm in a similar position with mine right now - it ran great until last summer when it started popping out the exhaust on driver side. Changed plugs, wires, O2 sensors and got a new tune and it ran great for a couple drives then started doing it again. Compression test went great but I couldn't get a good leakdown test done on it. It has been swallowing coolant since I built it and I only have 1,500 miles on it. Right now the heads are at the machine shop getting rebuilt and I am putting new LS9 head gaskets, LS7 lifters, lifter trays, pushrods, and rockers on it. Basically a top end rebuild. On top of that, I was worried that my hacked up engine harness may have been causing issues so I'm replacing that as well. I'll be into this project for about $1500 which is more than a 5.3 from the junkyard, but I didn't want to give up on this engine as it's a 6.0 LQ9 and I've done a lot of work to it already. I forgot to take a picture of the sad situation - parts laying around the truck, a half-taken apart engine, a huge coolant mess on the floor.
If money was no object, I would be putting an LT4 in it. The more realistic option if this doesn't go well is to pull the motor and rebuild the rotating assembly or even put a Gen 5 LT powertrain in it.
I understand your frustration. We put a lot of time and money into our trucks and to have issues like this is disappointing after so few miles. I chalk my experience up to the gamble of a salvage engine. I don't know how well the previous owner(s) maintained it, drove it, or how long it sat after being wrecked. The only way you can be sure that an engine is tip-top is to rebuild it yourself or buy a new one or one that has not sat for long and has low miles. Like others have said, stick with it, don't give up on it. It's just going to take time, money, and patience to fix it.
Worst case, you pull the motor, have the machine shop clean it really well (in addition to you cleaning it after you get it back from the machine shop), and you can rebuild it yourself. If the engine is as new as it sounds, you should be able to reuse your crank, rods, pistons, maybe even bearings. I would probably put new rings in it, oil pan gaskets, oil plugs/barbell, obviously head gaskets, ARP head bolts, and it should be in good shape. My dad and I just did our first start on a 5.3 LM7 we rebuilt it and it's a good feeling. This was something I wanted to do and the costs do add up when you're doing a complete rebuild and prepping for boost, but we can be sure that it was done right (or at least that a couple first-time engine builders followed all the right procedures and had the right tolerances). You can rebuild an engine in your garage with some pretty basic tools and a few specialty tools.
If money was no object, I would be putting an LT4 in it. The more realistic option if this doesn't go well is to pull the motor and rebuild the rotating assembly or even put a Gen 5 LT powertrain in it.
I understand your frustration. We put a lot of time and money into our trucks and to have issues like this is disappointing after so few miles. I chalk my experience up to the gamble of a salvage engine. I don't know how well the previous owner(s) maintained it, drove it, or how long it sat after being wrecked. The only way you can be sure that an engine is tip-top is to rebuild it yourself or buy a new one or one that has not sat for long and has low miles. Like others have said, stick with it, don't give up on it. It's just going to take time, money, and patience to fix it.
Worst case, you pull the motor, have the machine shop clean it really well (in addition to you cleaning it after you get it back from the machine shop), and you can rebuild it yourself. If the engine is as new as it sounds, you should be able to reuse your crank, rods, pistons, maybe even bearings. I would probably put new rings in it, oil pan gaskets, oil plugs/barbell, obviously head gaskets, ARP head bolts, and it should be in good shape. My dad and I just did our first start on a 5.3 LM7 we rebuilt it and it's a good feeling. This was something I wanted to do and the costs do add up when you're doing a complete rebuild and prepping for boost, but we can be sure that it was done right (or at least that a couple first-time engine builders followed all the right procedures and had the right tolerances). You can rebuild an engine in your garage with some pretty basic tools and a few specialty tools.
dhutton01
Backyard Hack
I’ve started using L86 dropouts. They can be found reasonably priced with low miles. They also come with 8 or 10 speed automatics. Awesome torque and horsepower for the money.
Don