Radiator Drain Plug
Advanced
Joined: Nov 2007
Posts: 64
Likes: 0
From: Ellicott City Maryland
Allegro, you will for sure need a new drain plug, get a replacement from your favorite GM dealer or FLAPS, it's a plastic threaded plug. when you get the replacement you'll know what you're looking for.
Drifting
Joined: Feb 2008
Posts: 1,765
Likes: 2
From: St. Clair Shores Mi
http://forums.corvetteforum.com/c5-t...tor-drain.html
from another site
"The radiator drain is at the lower, right corner of the radiator. Open it, let it run until the flow stops, close the drain and refill the system with water. Run the engine until the thermostat opens, shut off the engine, carefully release the pressure in the cooling system and open the radiator drain again. Repeat this procedure until the coolant coming out of the radiator runs clear. You may need to do this tedious flushing trick several times to get the water to run clear.Once the flushing is done, close the drain and fill the system with a 6.5 qts. of Dex-Cool (50%) and, optionally, a bottle of Red Line SuperCool. Add distilled water until it reaches the base of the surge tank neck. Start the engine and let it idle for a minute then cycle engine speed from idle to 3000 rpm and back until coolant temperature reaches 210¡F. Remove the tank cap, observing the cautions discussed previously. The coolant level should be about 1/2-in. above the "cold full" mark on the tank. If it is not, top off with distilled water, replace the cap, start the engine and repeat the above procedure. "
from another site
"The radiator drain is at the lower, right corner of the radiator. Open it, let it run until the flow stops, close the drain and refill the system with water. Run the engine until the thermostat opens, shut off the engine, carefully release the pressure in the cooling system and open the radiator drain again. Repeat this procedure until the coolant coming out of the radiator runs clear. You may need to do this tedious flushing trick several times to get the water to run clear.Once the flushing is done, close the drain and fill the system with a 6.5 qts. of Dex-Cool (50%) and, optionally, a bottle of Red Line SuperCool. Add distilled water until it reaches the base of the surge tank neck. Start the engine and let it idle for a minute then cycle engine speed from idle to 3000 rpm and back until coolant temperature reaches 210¡F. Remove the tank cap, observing the cautions discussed previously. The coolant level should be about 1/2-in. above the "cold full" mark on the tank. If it is not, top off with distilled water, replace the cap, start the engine and repeat the above procedure. "
Last edited by slothy; Dec 30, 2008 at 12:49 PM.
Drifting
Joined: Jan 2000
Posts: 1,660
Likes: 9
From: Charlotte, NC
I've drained my coolant several times on my 2000 coupe and have never needed a replacement drain plug.
The drain plug is on the passenger side of the radiator, facing the rear of the car, and is a whitish-colored plastic piece. Mine took an allen (alan?) wrench and it only turns about a 1/4 turn or so. I suggest to wiggle the wrench while turning. At the same time pull on the wrench towards the rear of the car as if you're trying to pull the drain plug out. This helps the plastic petcock to back out of the hole while rotating a 1/4 turn. This made a big difference and was really easy.
To get out the rest of the coolant, start your car and allow it to warm up to 200 degrees or so (check your DIC to ensure the temperature). This will open the thermostat and allow the remaining half of the coolant, which is trapped in the engine block and radiator hoses, to flow into the radiator and out of the car.
If you want to be thorough...once everything is drained, take off upper radiator hose (two clamps and you'll have to remove your air intake assembly) and the thermostat housing (on the passenger side). Then take a garden hose and blow out the engine as well as the radiator as best you can. No need to capture this water since its mainly just hose water...so make sure you're not doing this in a garage or you'll flood the place!
Let everything drain out.
Then put everything back together and begin filling with Dex Cool and Distilled Water. Take it for a drive and let everything heat up and air pockets to remove themselves. Then check the fluid level again.
Once you've done this, its really easy the second time around.
The drain plug is on the passenger side of the radiator, facing the rear of the car, and is a whitish-colored plastic piece. Mine took an allen (alan?) wrench and it only turns about a 1/4 turn or so. I suggest to wiggle the wrench while turning. At the same time pull on the wrench towards the rear of the car as if you're trying to pull the drain plug out. This helps the plastic petcock to back out of the hole while rotating a 1/4 turn. This made a big difference and was really easy.
To get out the rest of the coolant, start your car and allow it to warm up to 200 degrees or so (check your DIC to ensure the temperature). This will open the thermostat and allow the remaining half of the coolant, which is trapped in the engine block and radiator hoses, to flow into the radiator and out of the car.
If you want to be thorough...once everything is drained, take off upper radiator hose (two clamps and you'll have to remove your air intake assembly) and the thermostat housing (on the passenger side). Then take a garden hose and blow out the engine as well as the radiator as best you can. No need to capture this water since its mainly just hose water...so make sure you're not doing this in a garage or you'll flood the place!
Let everything drain out.
Then put everything back together and begin filling with Dex Cool and Distilled Water. Take it for a drive and let everything heat up and air pockets to remove themselves. Then check the fluid level again.
Once you've done this, its really easy the second time around.
Drifting
Joined: Jul 2007
Posts: 1,365
Likes: 1,818
If you are careful the drain plug will be fine to reuse. If you should damage it NAPA has a thumb screw replacement for about $5.50. Napa PN. 605-1371. (Don't ask why I know that PN.)
Last edited by 8VETTE7; Dec 30, 2008 at 02:12 PM.
Race Director
Joined: May 2001
Posts: 15,323
Likes: 2,077
From: Guelph, Ontario
Before I did the coolant in my car this past summer I bought a new replacement one from the GM dealer just in case I broke the original one. But even though my C5 is a 98, the original plug didn't give me any problems at all when I opened it up to drain the coolant.
Although for the low price of the plug, it's still probably a good idea to buy one just in case the original one breaks.
Although for the low price of the plug, it's still probably a good idea to buy one just in case the original one breaks.
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