Radiator Flush: Any Tips?
Thread Starter
Drifting
Joined: Aug 2005
Posts: 1,430
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From: Hamilton NJ
Radiator Flush: Any Tips?
Team,
79 L82. Drained stock rad to replace the lower hose and thermostat. Heater is off line and both feed lines are plugged at the intake and water pump. I want to flush the system and refresh the anti-freeze. My plan is to just open the fill cap and the drain petcock on the radiator and let clean water enter and exit the system with the engine running. After it runs clear I'll stop the engine and drain as much as possible, then fill it with half of the full system volume with AF and top off with clean water. Am I missing anything? What is the volume of the radiator core and lines and do I need to adjust for that when adding the AF?
Thanks, Steve
79 L82. Drained stock rad to replace the lower hose and thermostat. Heater is off line and both feed lines are plugged at the intake and water pump. I want to flush the system and refresh the anti-freeze. My plan is to just open the fill cap and the drain petcock on the radiator and let clean water enter and exit the system with the engine running. After it runs clear I'll stop the engine and drain as much as possible, then fill it with half of the full system volume with AF and top off with clean water. Am I missing anything? What is the volume of the radiator core and lines and do I need to adjust for that when adding the AF?
Thanks, Steve
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
here is a link to an older thread describing the proper flush materials
http://forums.corvetteforum.com/show...ghlight=oxalic
Here is a link to the GM TSB Instructuions for the proper proceedure. Just use the parts that apply.
http://www.geocities.com/b_gillie/TSB990602012.htm
Be sure to do the block plugs and use distilled when done.
If you thoroughly use this proceedure once, then a simple drain and refill can be done yearly to replace the SCA's and proper pH.
http://forums.corvetteforum.com/show...ghlight=oxalic
Here is a link to the GM TSB Instructuions for the proper proceedure. Just use the parts that apply.
http://www.geocities.com/b_gillie/TSB990602012.htm
Be sure to do the block plugs and use distilled when done.
If you thoroughly use this proceedure once, then a simple drain and refill can be done yearly to replace the SCA's and proper pH.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
I didn't go to the site referenced above, so this may be duplicate info:
If the radiator has been in service a long time without proper maintenance, you want to put radiator CLEANER in it, rather than to simply flush it. Flushing gets loose material and "gunk" [old antifreeze, etc.] out....but it won't get scale, etc. off of the fin surfaces. Those deposits are what keeps your radiator from cooling efficiently, and they need to be eliminated. Buy the radiator cleaner and follow the directions on the container. This is a 3-4 day cleaning while you operate the vehicle. I can't tell you how much difference this made in my car after I purchased it. Hope this helps.
If the radiator has been in service a long time without proper maintenance, you want to put radiator CLEANER in it, rather than to simply flush it. Flushing gets loose material and "gunk" [old antifreeze, etc.] out....but it won't get scale, etc. off of the fin surfaces. Those deposits are what keeps your radiator from cooling efficiently, and they need to be eliminated. Buy the radiator cleaner and follow the directions on the container. This is a 3-4 day cleaning while you operate the vehicle. I can't tell you how much difference this made in my car after I purchased it. Hope this helps.
Le Mans Master
Joined: May 1999
Posts: 6,692
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From: Texas
Several years ago, I had read elsewhere to use CLR in the radiator as a quick flush. People here told me don' do it - its too caustic. I did it anyway. Within 6 months, the water pump had to be replaced and the radiator started leaking and was replaced. Use the proper commercial flushes/cleaners, not some home remedy.
Thread Starter
Drifting
Joined: Aug 2005
Posts: 1,430
Likes: 8
From: Hamilton NJ
Thanks again, Steve
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Team Owner
Joined: Jan 2006
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From: Crossville TN
The instructions are on the bottle of rad. cleaner. If I remember correctly, you drain the radiator (only), put in cleaner, fill with water. Run for several hours. Drain radiator (only) again, fill with water, run again. Drain, then refill with whatever ratio of AF you want. Not complicated and does a great job. You won't believe the "stew" that comes out.
Instructor
Joined: Sep 2006
Posts: 240
Likes: 58
From: Jacksonville, Florida
If you plan on adding water and not using the pre mix 1/2 & 1/2 you will have to use distilled water. This way it is mineral free and will leave less if no deposits to corrode and block up the cleaned radiator. tap or "hose" water is one of the reasons a radiator gets clogged. Good luck and let us know how you make out. I will be doing mine as soon as the car is out of the paint shop.
Le Mans Master
Joined: Sep 2001
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From: Unreconstructed, South Carolina
Steve/wuttin:
Get the CLEANER ... prestone AS100 in canister ... aka GM P/N 12346500. Total waste of time to look for it at auto parts store. It has been discontinued by prestone and long before that it disappeared from retail shelves. There's still some old stock at some GM dealers ... start calling dealers NOW for GM 12346500 !
Get the CLEANER ... prestone AS100 in canister ... aka GM P/N 12346500. Total waste of time to look for it at auto parts store. It has been discontinued by prestone and long before that it disappeared from retail shelves. There's still some old stock at some GM dealers ... start calling dealers NOW for GM 12346500 !
Melting Slicks
Joined: Apr 2000
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Likes: 6
Be sure to adjust your heater controls to maximize the coolant flow through the heater core when flushing or you'll be leaving a significant portion of the system untouched to continue to plug up and recontaminate the rest.
Racer
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From: san diego
steve
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Melting Slicks
Joined: May 1999
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From: Moon Township PA
Since you are doing a complete flush, don't forget the block drains. You should have two drains, one on each side, near the engine mount. Remove these two bolts and let the block drain. There is a pretty substantial amount of coolant left in the block if you don't drop the drain bolts. Very easy to do.
Gary
Gary
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From: AL
In my city, you can take automotive fluids to a designated location once a month for disposal (no charge). this is provided by the garbage collection outfit.
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kdf
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My advice is to do your best to NOT use any of the radiator flushes. If the system is that bad,.....I can almost guarantee you that you will replace freeze plugs, water pump and other stuff very soon after you do all of this. All of that nice crud is also sealing over a lot od rust. When you remove it..it will soon eat through.
In my earlier days as a mechanic..it was very common for customers to come in with all sorts of issues soon after using the flush kits.
I'd do my best to reverse flush with water and call it good and hope.
JIM
In my earlier days as a mechanic..it was very common for customers to come in with all sorts of issues soon after using the flush kits.
I'd do my best to reverse flush with water and call it good and hope.
JIM
Team Owner
Joined: Jan 2006
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From: Crossville TN
You'll have to be the judge on what condition your radiator is in. If the antifreeze was kept reasonably "fresh", you shouldn't have a rust problem. But you will have a lime/scale problem (which the cleaner should fix). If you bought the car and it had a cruddy radiator with lots of rust in it, I would agree that freeze plug removal & replacement might be a good idea. But I would still run the cleaner through it before pulling the freeze plugs out.