69 427 coolant flush
Melting Slicks
Joined: Aug 2005
Posts: 2,683
Likes: 34
From: Working on the car NY
Don't buy the pre-mix stuff. It's a waste of money. Buy the 100% and add your own water at a 50/50 mix. 2 gallons of the 100% is what you need. Unless you drain the block and remove all the hoses, about 2 gallons is all you will be able to get in the radiator.
Drifting
Joined: Nov 2002
Posts: 1,692
Likes: 208
From: Loveland, CO
It's hard to get all the old stuff out of the block by just opening drain tap on the radiator. You leave a lot of old crud in the system thay way. If you can get to the block drain taps, that is the best way, but can be a bit challenging. Another option is one of those flush kits that allow you to hook up a garden hose and the run the motor to flush all the old out. Anyway you go, it is a project.
Did you mean to imply that you only have water in the system now? Not good, unless you added some rust inhibitors, and you don't get full cooling effect with just water.
Ralph
Did you mean to imply that you only have water in the system now? Not good, unless you added some rust inhibitors, and you don't get full cooling effect with just water.
Ralph
Pro
Joined: Nov 2007
Posts: 710
Likes: 0
From: Northern Florida
I always use Prestones H.D. Cooling System Cleaner then flush using their backflush kit . I open the block drains while flushing too. I put in just the amount of antifreeze that suffices for the lowest expected outdoor temp. for my locale during the winter ..if youre going to drive with it in for summer months too. In the summer ill put in a bottle of water wetter and reduce the antifreeze mix .
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
The only other suggestion that I would provide is:
Once you fill the system with 50/50 mix of glycol antifreeze and distilled water, just leave it that way for 2-3 years. That 50/50 mix is a better dissipator of heat than just water and it also prevents corrosion [rust] inside the block. It's just better for the engine than water only.
Once you fill the system with 50/50 mix of glycol antifreeze and distilled water, just leave it that way for 2-3 years. That 50/50 mix is a better dissipator of heat than just water and it also prevents corrosion [rust] inside the block. It's just better for the engine than water only.
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Pro
Joined: Nov 2007
Posts: 710
Likes: 0
From: Northern Florida
The only other suggestion that I would provide is:
Once you fill the system with 50/50 mix of glycol antifreeze and distilled water, just leave it that way for 2-3 years. That 50/50 mix is a better dissipator of heat than just water and it also prevents corrosion [rust] inside the block. It's just better for the engine than water only.
Once you fill the system with 50/50 mix of glycol antifreeze and distilled water, just leave it that way for 2-3 years. That 50/50 mix is a better dissipator of heat than just water and it also prevents corrosion [rust] inside the block. It's just better for the engine than water only.
1. Prevent the block from cracking or from freeze plug failure, in cold weather when the car is not being used.
2. To prevent possible freezeup of stagnant water in the heating coil, when the a/c is used in the summertime ......as the heating coil is downstream of the a/c evaporator and could see discharge air of 32 f. or below .
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
Big difference between flushing/cleaning and draining/refill.
If your system is clean, then a drain/refill is good enough, but I would do it every 2 years, no matter what they recommend. Pretty cheap.
In all cases, using the block drains to completely drain the system is best.
The 50/50 mix uses deionized water, that is a step better than distilled. Use at least distilled. You always need some type of rust inhibitor, whether antifreeze or other.
Over 80% of engine failures stem from cooling system neglect.
If your system is clean, then a drain/refill is good enough, but I would do it every 2 years, no matter what they recommend. Pretty cheap.
In all cases, using the block drains to completely drain the system is best.
The 50/50 mix uses deionized water, that is a step better than distilled. Use at least distilled. You always need some type of rust inhibitor, whether antifreeze or other.
Over 80% of engine failures stem from cooling system neglect.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Indy cars and other race cars run only water because they don't need antifreeze and because no one wants glycol (or other substance) on the race track after a wreck.
You are correct that the specific heat of a 50/50 mix of water and glycol is less than plain water; it's about 85-90% of water's capacity.
If you have no need to protect your engine from freezing conditions, just put something for corrosion prevention in the distilled water and leave it that way. If you do experience freezing conditions, it's a total waste of time to change coolants from water to antifreeze every year....unless you have a cooling system that is inadequate for your engine.
You are correct that the specific heat of a 50/50 mix of water and glycol is less than plain water; it's about 85-90% of water's capacity.
If you have no need to protect your engine from freezing conditions, just put something for corrosion prevention in the distilled water and leave it that way. If you do experience freezing conditions, it's a total waste of time to change coolants from water to antifreeze every year....unless you have a cooling system that is inadequate for your engine.
Pro
Joined: Nov 2007
Posts: 710
Likes: 0
From: Northern Florida
Indy cars and other race cars run only water because they don't need antifreeze and because no one wants glycol (or other substance) on the race track after a wreck.
You are correct that the specific heat of a 50/50 mix of water and glycol is less than plain water; it's about 85-90% of water's capacity.
If you have no need to protect your engine from freezing conditions, just put something for corrosion prevention in the distilled water and leave it that way. If you do experience freezing conditions, it's a total waste of time to change coolants from water to antifreeze every year....unless you have a cooling system that is inadequate for your engine.
You are correct that the specific heat of a 50/50 mix of water and glycol is less than plain water; it's about 85-90% of water's capacity.
If you have no need to protect your engine from freezing conditions, just put something for corrosion prevention in the distilled water and leave it that way. If you do experience freezing conditions, it's a total waste of time to change coolants from water to antifreeze every year....unless you have a cooling system that is inadequate for your engine.
Instructor
Joined: May 2011
Posts: 191
Likes: 1
From: Orange Ca
Why not use the pre-mix stuff. I thought I read somewhere on this forum that the pre-mix is already 50/50 and mixed with distilled or similar water? Cost difference aside...is there something wrong with the pre-mix?
Drifting
Joined: Oct 2005
Posts: 1,528
Likes: 148
From: East London/SW Essex UK
No...the best heat dissipator is water alone., without antifreeze. Studies confirm this and can be googled -- further, Indy Cars run straight water . As for rust protection and lubricating of the water pump seals, a bottle of Redlines Water Wetter has these protective properties as well as offering a superior surfactant in reducing cooling system temps . The reason to use some antifreeze is :
1. Prevent the block from cracking or from freeze plug failure, in cold weather when the car is not being used.
2. To prevent possible freezeup of stagnant water in the heating coil, when the a/c is used in the summertime ......as the heating coil is downstream of the a/c evaporator and could see discharge air of 32 f. or below .
1. Prevent the block from cracking or from freeze plug failure, in cold weather when the car is not being used.
2. To prevent possible freezeup of stagnant water in the heating coil, when the a/c is used in the summertime ......as the heating coil is downstream of the a/c evaporator and could see discharge air of 32 f. or below .
Melting Slicks
Joined: Aug 2005
Posts: 2,683
Likes: 34
From: Working on the car NY
Nope, BUT unless the block is completly drained, you'll need 100% AF to mix with the approximate 8 quarts of regular water sitting in the block to give you the 50/50 mix. I don't like to "mess" with the engine block bolts to get the block completly dry so after draining and flushing the system with a hose, I can just about get 2 gallons of 100% AF in the radiator to fill the system which will then give me the 50/50 mix. If I filled the rad with the pre-mix, I'd probably then be 25% AF/ 75% water which would help me in zero degree weather.
Instructor
Joined: May 2011
Posts: 191
Likes: 1
From: Orange Ca
Nope, BUT unless the block is completly drained, you'll need 100% AF to mix with the approximate 8 quarts of regular water sitting in the block to give you the 50/50 mix. I don't like to "mess" with the engine block bolts to get the block completly dry so after draining and flushing the system with a hose, I can just about get 2 gallons of 100% AF in the radiator to fill the system which will then give me the 50/50 mix. If I filled the rad with the pre-mix, I'd probably then be 25% AF/ 75% water which would help me in zero degree weather.
