Excessive Coolant Flushing
Thread Starter
Racer
Joined: Jun 2017
Posts: 495
Likes: 85
Excessive Coolant Flushing
I recently changed out my water pump in an effort to get rid of a squeaking noise on the engine accessories of my 1972 sbc.
This, of course, requires you drain the coolant.
When i drained it, as you can probably expect, it was brown and looked pretty terrible. So i went through the normal coolant flushing process. I even opened up the engine block coolant drains on the driver's side.
From what I've read, you are suppose to keep flushing until it runs clear, but I have gone through so many cycles and it still looks brown. I've probably gone through 7 cycles of flushing, and it's still brown. I even pour some extra water through the engine when i drain it to try to get any residue out. Even after drains and just pouring water through, im not able to get the water coming from the block drains to run clear. I usually drain, then pour about 10 gallons through, then refill and flush again.
I took a quick look at the oil, and from what I can tell, there doesn't seem to be any water in it (kind of milk shake like, right?).
It's starting to get ridiculous how many gallon jugs i bring to hazardous material disposal.
At this point I'm not sure what to do. Just keep flushing?
I used the blue devil cleaner and the Prestone. Should i use a different cleaner?
Can i ever expect this to run clear?
This, of course, requires you drain the coolant.
When i drained it, as you can probably expect, it was brown and looked pretty terrible. So i went through the normal coolant flushing process. I even opened up the engine block coolant drains on the driver's side.
From what I've read, you are suppose to keep flushing until it runs clear, but I have gone through so many cycles and it still looks brown. I've probably gone through 7 cycles of flushing, and it's still brown. I even pour some extra water through the engine when i drain it to try to get any residue out. Even after drains and just pouring water through, im not able to get the water coming from the block drains to run clear. I usually drain, then pour about 10 gallons through, then refill and flush again.
I took a quick look at the oil, and from what I can tell, there doesn't seem to be any water in it (kind of milk shake like, right?).
It's starting to get ridiculous how many gallon jugs i bring to hazardous material disposal.
At this point I'm not sure what to do. Just keep flushing?
I used the blue devil cleaner and the Prestone. Should i use a different cleaner?
Can i ever expect this to run clear?
Burning Brakes
Joined: May 2013
Posts: 789
Likes: 129
From: Los Banos CA
I think they still sell 'back flush kits' that splice into your heater hose, and allow a garden hose to be connected to it, and forces water thru the system and out the radiator fill cap. Some people don't like them, as they leave 'tap water' in your system instead of distilled water.
One word of warning though - if your coolant was that bad, keep an eye on your heater core. There's a good chance that it's nearing failure, and the flushing and/or back flushing might actually speed up the failure slightly (but not a reason to avoid flushing).
One word of warning though - if your coolant was that bad, keep an eye on your heater core. There's a good chance that it's nearing failure, and the flushing and/or back flushing might actually speed up the failure slightly (but not a reason to avoid flushing).
Thread Starter
Racer
Joined: Jun 2017
Posts: 495
Likes: 85
I have a coolant flush T-fitting that was installed by the previous owner, but i do not have the tube that suppose to plug into the radiator cap area. I have been adding the water and flushing solution into this T fitting rather than through the radiator cap.
The problem with using the hose is I dont have a 50 gallon drum for the contaminated flushed water.
I know rusty water isn't hazardous, but this is an original numbers block, and I have to believe if the water is still so brown, there is some other non-rust stuff in there.
Once I flush, refill, short drive, drain, the water definitely has a smell to it. I can't tell if it smells like oil.
If I don't see any water in the oil, is it safe to say there shouldnt be any oil in the coolant?
How can I tell?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You may have to hook it all back up with just water in it, THEN get some radiator cleaner and follow the directions. You find it in the same section as radiator flush; but it will dislodge the residual CRUD that simple flushing cannot do. I suspect you just have years of rust/carbonate/glycol muck stuck in the nooks and crannies of the block, etc.
Racer
Joined: Aug 2013
Posts: 339
Likes: 54
From: Fayetteville NC
Cheap way of flushing. When I was in the Navy and ran out of evaporator cleaner we used a bag of citrus powder aka lemon juice to clean and flush the internal tubes of a coil. It worked every time. Pour a large package of lemon juice in a container and use hot water to melt the crystal. Pour it in your radiator and run your engine to operating temperature for 15 min and let it sit for another 30 min before draining and flushing with plain water. If you suspect any oily substance, I've heard that dawn liquid dish washing detergent will break it up.
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Thread Starter
Racer
Joined: Jun 2017
Posts: 495
Likes: 85
Cheap way of flushing. When I was in the Navy and ran out of evaporator cleaner we used a bag of citrus powder aka lemon juice to clean and flush the internal tubes of a coil. It worked every time. Pour a large package of lemon juice in a container and use hot water to melt the crystal. Pour it in your radiator and run your engine to operating temperature for 15 min and let it sit for another 30 min before draining and flushing with plain water. If you suspect any oily substance, I've heard that dawn liquid dish washing detergent will break it up.
When i look at the flush + cleaner made by prestone, it looks like it uses some kind of citric acid and water.
Thread Starter
Racer
Joined: Jun 2017
Posts: 495
Likes: 85
You may have to hook it all back up with just water in it, THEN get some radiator cleaner and follow the directions. You find it in the same section as radiator flush; but it will dislodge the residual CRUD that simple flushing cannot do. I suspect you just have years of rust/carbonate/glycol muck stuck in the nooks and crannies of the block, etc.
Is there a specific cleaner you can recommend?
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
For a flush, they don't sell the good old Prestone flush anymore, but wood bleach, oxalic acid, is the same thing. As for the "nuetralizer", I forget what works. Maybe baking soda?
Burning Brakes
Joined: Aug 2013
Posts: 1,071
Likes: 322
From: palm springs ca
I recently changed out my water pump in an effort to get rid of a squeaking noise on the engine accessories of my 1972 sbc.
This, of course, requires you drain the coolant.
When i drained it, as you can probably expect, it was brown and looked pretty terrible. So i went through the normal coolant flushing process. I even opened up the engine block coolant drains on the driver's side.
From what I've read, you are suppose to keep flushing until it runs clear, but I have gone through so many cycles and it still looks brown. I've probably gone through 7 cycles of flushing, and it's still brown. I even pour some extra water through the engine when i drain it to try to get any residue out. Even after drains and just pouring water through, im not able to get the water coming from the block drains to run clear. I usually drain, then pour about 10 gallons through, then refill and flush again.
I took a quick look at the oil, and from what I can tell, there doesn't seem to be any water in it (kind of milk shake like, right?).
It's starting to get ridiculous how many gallon jugs i bring to hazardous material disposal.
At this point I'm not sure what to do. Just keep flushing?
I used the blue devil cleaner and the Prestone. Should i use a different cleaner?
Can i ever expect this to run clear?
This, of course, requires you drain the coolant.
When i drained it, as you can probably expect, it was brown and looked pretty terrible. So i went through the normal coolant flushing process. I even opened up the engine block coolant drains on the driver's side.
From what I've read, you are suppose to keep flushing until it runs clear, but I have gone through so many cycles and it still looks brown. I've probably gone through 7 cycles of flushing, and it's still brown. I even pour some extra water through the engine when i drain it to try to get any residue out. Even after drains and just pouring water through, im not able to get the water coming from the block drains to run clear. I usually drain, then pour about 10 gallons through, then refill and flush again.
I took a quick look at the oil, and from what I can tell, there doesn't seem to be any water in it (kind of milk shake like, right?).
It's starting to get ridiculous how many gallon jugs i bring to hazardous material disposal.
At this point I'm not sure what to do. Just keep flushing?
I used the blue devil cleaner and the Prestone. Should i use a different cleaner?
Can i ever expect this to run clear?
Dom
Racer
Joined: Aug 2013
Posts: 339
Likes: 54
From: Fayetteville NC
Yes. Any grocery store should carry the powdered lemon juice. I googled it and several popped up. Just remember, no sugar lol.good luck.
Last edited by ENCSDOUG; Feb 7, 2018 at 08:36 AM.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Prestone makes radiator cleaner and radiator flush. I'm sure that there are other manufacturers of similar stuff. Why not use what has already been prepared for doing this job...rather than inventing something.
You need something with a solvent in it to cut the 'muck'; and you need something that will dissolve the lime buildup inside the radiator. Radiator cleaner will do both. Just sayin'.....
You need something with a solvent in it to cut the 'muck'; and you need something that will dissolve the lime buildup inside the radiator. Radiator cleaner will do both. Just sayin'.....