Thread: Coolant Flush : How to?

While in most cases I am a huge voice for doing it yourself, the cooling system is something that having it professionally done is worth it in the long run. And that is simply because of the time that it takes and the fact a professional flush can do a much better job in cleaning out that gunk you speak of.

I have done coolant flushes myself and the heat up and cool down cycles are time consuming, you need to drain the radiator, pull the lower hose and pull out the front knock sensor to make sure your getting as much out as you can, then you have to repeat all that a few times to get it done right.

A professional flush can be done with the engine running and they do a good job of cleaning out the system. $70 is a pretty decent price for it being done at a dealership. I had mine professionally flushed and I think I paid $85 and that wasnt at a dealership and if he can back flush it and clean out the heater core, I think that is a decent deal.

I agree with Scotty here. However IF you decide you want to try it yourself here is a link to one write-up...Although I believe I've seen a more detailed write-up elsewhere ClubGP:

Here is a way more detailed write-up from one of the guys over at newimpala.com


Important
Do not use a chemical flush.


Store used coolant in a properly labeled container. Do not pour used coolant down a drain. Ethylene glycol antifreeze is a very toxic chemical. Do not dispose of coolant into the sewer system or ground water. This is illegal and ecologically unsound.

Various methods and equipment can be used to flush the cooling system. If special equipment is used, such as a back flusher, follow the manufacturer's instruction.

When the cooling system becomes contaminated, the cooling system should be flushed thoroughly to remove the contaminants before the engine is seriously damaged.

Drain the cooling system. Refer to Draining and Filling Cooling System .
Remove the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement .
Clean and flush the coolant recovery reservoir with clean, drinkable water.
Install the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement .
Follow the drain and fill procedure using only clean, drinkable water. Refer to Draining and Filling Cooling System .
Run the engine for 20 minutes.
Stop the engine.
Drain the cooling system. Refer to Draining and Filling Cooling System .
Repeat the procedure if necessary, until the fluid is nearly colorless.
Fill the cooling system. Refer to Draining and Filling Cooling System .


Draining and Filling Cooling System
Draining Procedure
Caution
With a pressurized cooling system, the coolant temperature in the radiator can be considerably higher than the boiling point of the solution at atmospheric pressure. Removal of the surge tank cap, while the cooling system is hot and under high pressure, causes the solution to boil instantaneously with explosive force. This will cause the solution to spew out over the engine, the fenders, and the person removing the cap. Serious bodily injury may result.


Park the vehicle on a level surface.
Remove the coolant pressure cap.
Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Place a drain pan under the drain (c!!!).
Open the radiator drain (c!!!).
Drain the cooling system.
If a complete engine block drain is required, remove the engine block drain plug.
Inspect the coolant.
Follow the appropriate procedure based on the condition of the coolant.
Normal in appearance -- follow the filling procedure.
Discolored -- follow the flush procedure. Refer to Flushing .
Filling Procedure
Tools Required
J 23688 Coolant and Battery Fluid Tester


Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.


Close the radiator drain (c!!!). Tighten
Tighten the radiator drain (c!!!) to 2 N·m (18 lb in).

If the engine block drain plug was removed, perform the following:
Apply pipe sealer to the drain plug.
Install the drain plug. Tighten
Tighten the drain plug to 22 N·m (16 lb ft).

Lower the vehicle.
Open the cooling system bleeder screws.

Important
Use a 50/50 mixture of DEX-COOL antifreeze and deionized water.


Slowly fill the cooling system with a 50/50 coolant mixture.
Close the cooling system bleeder screws.
Install the coolant pressure cap.
Start the engine.
Run the engine at 2,000 - 2,500 RPM until the engine reaches normal operating temperature.
Allow the engine to idle for 3 minutes.
Shut the engine off.
Allow the engine to cool.
Top off the coolant as necessary.
Inspect the concentration of the engine coolant. Using the J 23688 .
Rinse away any excess coolant from the engine and the engine compartment.
Inspect the cooling system for leaks.


Coolant Recovery Reservoir Replacement
Removal Procedure
Remove the cross vehicle brace. Refer to Brace Replacement - Cross Vehicle in Body Front End.



Reposition the reservoir hose clamp (1).
Remove the reservoir hose from the radiator overflow neck.
Remove the coolant recovery reservoir nuts (2) from the shock tower studs.
Remove the coolant recovery reservoir (3) from the lower retainer and the shock tower studs .
Drain the coolant from the recovery reservoir in to a clean container.
Installation Procedure




Install the coolant recovery reservoir (3) onto the lower retainer and the shock tower studs.

Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.


Install the coolant recovery reservoir nuts (2) to the shock tower studs. Tighten
Tighten the nuts to 3.3 N·m (29 lb in).

Lubricate the reservoir hose with clean water. Route the hose to the radiator overflow neck fitting.
Install the coolant reservoir hose (1) to the overflow neck fitting.
Install the reservoir hose and clamp (1), with the clamp tabs at the 11 o'clock position, to the radiator overflow fitting on the radiator filler neck. The hose end must be flush against the radiator filler neck. Seat the clamp squarely between the radiator filler neck and the flared end of the fitting.
Install the cross vehicle brace. Refer to Brace Replacement - Cross Vehicle in Body Front End.
Fill the coolant recovery reservoir to the proper level.




Thanks to Bobspala for submitting this

Originally Posted by 04CompG

Thanks for the replies. I will go ahead and have my friend do it for the heater core backwash and peace of mind.

Good choice.

Thanks for your write-up as well. While similar to the link from CGP it is a nice addition with a few more details.