Coolant Change - 2002
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From: Huntley Illinois
Coolant Change - 2002
I'm making my first attempt at draining the radiator. I'm not new to this but I am doing it for the first time on the vet.
All I have read is "Using a 1/4" drive ratchet, gently turn the drain valve 1/4 turn counterclockwise. If the valve resists turning, use one hand to gently pull the valve outward (towards the rear of the Corvette) while still trying to back it out."
I've done this but as I open the drain plug I feel the plug definately "snap" into another position at maybe 1/8 of a turn on the ratchet.
For fear of breaking the drain **** plug off what are I doing wrong? I have no flow at all.
The GM Service Manual talks about tightening the drain **** to 18 inch pounds. I don't see why you would torque this valve when you can feel it "snap" into position. I can't believe there is a "torque" on the valve I'm seeing.
Thanks in advance.
All I have read is "Using a 1/4" drive ratchet, gently turn the drain valve 1/4 turn counterclockwise. If the valve resists turning, use one hand to gently pull the valve outward (towards the rear of the Corvette) while still trying to back it out."
I've done this but as I open the drain plug I feel the plug definately "snap" into another position at maybe 1/8 of a turn on the ratchet.
For fear of breaking the drain **** plug off what are I doing wrong? I have no flow at all.
The GM Service Manual talks about tightening the drain **** to 18 inch pounds. I don't see why you would torque this valve when you can feel it "snap" into position. I can't believe there is a "torque" on the valve I'm seeing.
Thanks in advance.
Last edited by Randyman2002; Aug 28, 2012 at 02:29 PM. Reason: addition
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I recently drained my 2004 when I installed my low temp stat.
I also pulled the drain **** while turning it counter clockwise. I didn't not hear any type of snap, so perhaps yours was actually over-tightened originally.
Definitely do not force anything, however try pulling and turning again. The coolant immediately started draining for me, however once it starts, it's a slow drain. While you wait, go have a beer because it takes about 20-30 minutes to fully drain.
I also pulled the drain **** while turning it counter clockwise. I didn't not hear any type of snap, so perhaps yours was actually over-tightened originally.
Definitely do not force anything, however try pulling and turning again. The coolant immediately started draining for me, however once it starts, it's a slow drain. While you wait, go have a beer because it takes about 20-30 minutes to fully drain.
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From: Huntley Illinois
Got it to open.... turned the plug,(be careful because mine is not an actual quater turn like I've read, wiggled the plug by hand many times and used a very small screw driver to gently "pop" the plug out of its seat.
Draining now, but very slowly!
Draining now, but very slowly!
Last edited by Randyman2002; Aug 28, 2012 at 06:14 PM.
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Mine was a very small turn as well. In fact, I was more nervous about closing it afterwards because it seemed like it didn't take much to open. I was scared the fluid I was going to add was going to drain out, however I kept checking and it never leaked.
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As a precaution, I would have a new plug available to replace the existing plug. Examination of the new plug will make clear how to remove the existing plug.
That said. the existing plug should allow drainage after 90 degrees of turn out.
There may be gunk at the bottom of the radiator blocking flow out the drain, in which case the original plug should be removed completely and the hole probed gently with a soft wood dowell shaped to not scratch the radiator plug bore in the radiator. This surface needs to stay smooth so that the new plug "O" ring will seal against it.
Another option is to use a section of small hose which fits the plug opening and to gently blow into the plug opening to dislodge gunk. Make sure the system is open, coolant cap off.
That said. the existing plug should allow drainage after 90 degrees of turn out.
There may be gunk at the bottom of the radiator blocking flow out the drain, in which case the original plug should be removed completely and the hole probed gently with a soft wood dowell shaped to not scratch the radiator plug bore in the radiator. This surface needs to stay smooth so that the new plug "O" ring will seal against it.
Another option is to use a section of small hose which fits the plug opening and to gently blow into the plug opening to dislodge gunk. Make sure the system is open, coolant cap off.
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I pulled the lower radiator hose at the water pump. Screw the slow draining petcock
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Glad you got it to work right and got that old coolant out.
Melting Slicks
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Very important precaution. I used the Prestone brand DexCool. Do not use the conventional green stuff or you will damage your cooling system. Also, make sure that you mix it (preferably 50/50) with distilled water only.
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I'm not sure where you guys get your information but green antifreeze is safe to use. Read your owners manual. The only difference is a shorter recommended change interval. Prestone also says it's safe to use.
Dexcool is far more corrosive and worse for your system IF it is exposed to air.
Not starting a war just stating the facts. Before anyone trys to argue read the owners manual, I have.
Dexcool is far more corrosive and worse for your system IF it is exposed to air.
Not starting a war just stating the facts. Before anyone trys to argue read the owners manual, I have.
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I'm not sure where you guys get your information but green antifreeze is safe to use. Read your owners manual. The only difference is a shorter recommended change interval. Prestone also says it's safe to use.
Dexcool is far more corrosive and worse for your system IF it is exposed to air.
Not starting a war just stating the facts. Before anyone trys to argue read the owners manual, I have.
Dexcool is far more corrosive and worse for your system IF it is exposed to air.
Not starting a war just stating the facts. Before anyone trys to argue read the owners manual, I have.
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It will autodestruct in 15 seconds.....
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I've wondered that myself. Seems like just pouring the stuff in it would be exposed to air. My guess is the vette uses a closed pressurized system where other vehicles use an unpressurized overflow tank which is open to the atmosphere pretty much. I tried googling but I gave up. A bunch of the horror stories were more about intake gasket problems.
Last edited by Camjamsdad; Aug 29, 2012 at 08:32 PM.
Melting Slicks
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I'm not sure where you guys get your information but green antifreeze is safe to use. Read your owners manual. The only difference is a shorter recommended change interval. Prestone also says it's safe to use.
Dexcool is far more corrosive and worse for your system IF it is exposed to air.
Not starting a war just stating the facts. Before anyone trys to argue read the owners manual, I have.
Dexcool is far more corrosive and worse for your system IF it is exposed to air.
Not starting a war just stating the facts. Before anyone trys to argue read the owners manual, I have.
Page 5.24
"Notice: When adding coolant, it is important that you use only Dex-cool (silicate-free) coolant. If coolant other than Dex-cool is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner - at 30k miles or 24 months, whichever occurs first. Damage caused by the use of coolant other than Dex-cool is not covered by your new vehicle warrant"
Page 6.13 Recommended fluids
"Engine Coolant: 50/50 mixture of clean, drinkable water and use only Dex-cool coolant. See Engine Coolant on page 5.23."
To me, it is pretty clear that using anything but Dex-cool is at your own risk and may cause corrosion. But, what do GM engineers know?
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Since coolant spashes easily anyway, pulling the hose is faster but just makes a bigger mess. I just open the drain and do something else while it is draining.
As far as mixing coolants, as long as Dexcool is available, why would anyone risk using the old green coolant?
I have never figured out exactly what causes Dexcool to form sludge in some systems. Never had a problem with the Corvette, or the vented, non-pressurized overflow tank on the Impala, but the Malibu, even with a pressurized overflow tank would still form a brown sludge in the tank..
As far as mixing coolants, as long as Dexcool is available, why would anyone risk using the old green coolant?
I have never figured out exactly what causes Dexcool to form sludge in some systems. Never had a problem with the Corvette, or the vented, non-pressurized overflow tank on the Impala, but the Malibu, even with a pressurized overflow tank would still form a brown sludge in the tank..
Last edited by TEXHAWK0; Aug 30, 2012 at 06:06 PM.
