Special Procedure When Filling Coolant?

[Bizzo]

Today I want to flush the coolant in my car and replace it with new coolant. Under the hood I notice there's a caution sticker saying there is a special procedure when filling the car with coolant. Anybody know what this is? I don't have an owners manual and on my 95 corsica all you had to do was fill it through the overflow.

[Slade901]

Mostly the caution is about taking off the the radiator cap only when the engine is cold/warm because if the pressure is still there in the radiator then it could injure you when you try to open the radiator cap while the engine is still hot or radiator has still high pressure.

 

Remove the radiator cap. Put some bucket at the bottom of the radiator to catch the drained coolant.

Loosen the drain plug (don't remove) which is located just at the lower side of the of the radiator and let it drain the old coolant. Pour some water (water hose) trough the radiator cap for about a minute.

 

Tighten the drain plug and pour water again through the radiator cap and fill the radiator. Close the radiator cap and start the car for 10 minutes and turn it off and let it sit for 10 minutes.

 

Remove the radiator cap and loosen the drain plug and once the radiator is empty then close the drain plug. Pour some radiator flush liquid and then fill the radiator with water and close the radiator cap. Start the car for 10 minutes and turn it off and let it sit for 10 minutes.

 

Remove the radiator cap and loosen the drain plug and once the radiator is empty then close the drain plug. Fill the radiator with water and close the radiator cap. Start the car for 10 minutes and turn it off and let it sit for 10 minutes.

 

Remove the radiator cap and loosen the drain plug and once the radiator is empty then close the drain plug. Fill the radiator with 70/30 coolant water mixture and close the radiator cap. Start the car for 10 minutes and check the coolant reservoir level and top it off to the warm level with a 70/30 coolant water mixture. Turn it off and let it sit for 10 minutes.

[Justin]

Here's my method, simplified.

 

Pull the drain plug out of the bottom of the radiator, and remove the rad. cap to allow the coolant to drain faster.

 

Find one of the heater hoses that go from the engine to the firewall, they're like the small 1" hoses. Remove one end of the hose that's easy to get to. Put a garden hose with nozzle on the end of the hose and let her rip, flush coolant through until the water coming out of the radiator drain and the other spot where your heater hose was connected is clear, with no coolant in it.

 

Then put your garden hose on the spot where the hose connects, and flush it that way for a while, just making sure it's all clear.

 

Let all the water that will drain out drain out, then plug your rad. drain agian.

 

Start filling the rad. with new coolant, I leave the heater hose off until I get green coolant spilling out, and this helps bleed the system too.

 

Reinstall the hose clamp on the heater hose, and fill the car the rest of the way with coolant. With the water left in the engine block, you should be ok just adding coolant, our cars should take like 1.5-2 gallons. This will give you at least a 50-50 mix, which is all you should need, since that's good to at least -30.

 

Start the car and just let it warm up, keep the rad full if the coolant gets low. When the top rad hose is hot, the thermostat is open and you're set.

 

Your car may have a small bleed screw somewhere near the top of the engine, you can unscrew that after you start it until coolant starts coming out, then close and tighten it.

 

If you flush it this way you get all the old coolant out, you can't be sure with that other way above, and this way if faster too, since you don't have to wait for the car to warm up like 3 times.

[GRANDFURY]

I just air locked my rad....booooooooooo.......I'm an idiot......but I got it done now I flushed mine the same way stated above and seems to be a good way to do it.

[Slade901]

You're suppose to use a Radiator Flush (liquid) prior to putting a new coolant mixture.

 

The Radiator Flush has some chemical in it and when circulated with engine running for a couple of minutes, it helps to dislodged any crud or any crud build up. After draining the Radiator Flush mixture, then you can put in your coolant.

 

Simply draining the old coolant won't get rid of any crud build up.

[jesse]

The warning refers to airlock and disposal. It is sometimes very hard, if not impossible to get all the air out when you drain and fill in the conventional manner.

The ideal method would be to REPLACE the fluid, by pushing it out with new coolant in a SEALED environment.