Is there a specific procedure to change C5 (99 Nassau Blue) coolant procedure. Specifically is there a need to air purge the system after refill?

Thanks in advance.. I will be changing Thermo to 170 and refilling soon.

See ya'll at the C5 BGK event 4/02

 

Draining and Filling Cooling System

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.

Important
If the procedure below is not followed a low or high coolant level condition and/or vehicle damage could result.


1) Park the vehicle on a level surface.
2) Remove the surge tank cap:
3)Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
4) Place a drain pan under the drain fowl.
5) Open the radiator drain fowl.
6) Allow the cooling system to drain completely.
7) Inspect the engine coolant for the following:
Discolored -- follow the flush procedure below.
Normal in appearance -- continue with the next step.

Notice
When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.

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.


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

9) Fill the cooling system through the surge tank.
10) Fill the cooling system with a 50/50 mixture of DEX-COOL® coolant and deionized water.
11) Start the engine.
12) Allow the engine to idle for 1 minute.
13) Install surge tank cap.
14) Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant temperature reaches 99°C (210°F).
15)Shut off the engine.
16) Remove the surge tank cap.
17) Start the engine.
18) Allow the engine to Idle for 1 minute. Fill the surge tank to 12.7 mm (0.5 in) above the COLD FULL mark on the surge tank.
19) Install the surge tank cap.
20) Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant reaches 99°C (210°F).
21) Shut off the engine.
22) Remove the surge tank cap.
23) Top off the coolant as necessary, 12.7 mm (0.5 in) above FULL COLD mark on the surge tank.
24) Rinse away any excess coolant from the engine and the engine compartment.
25) Inspect the concentration of the engine coolant.
26) Install the surge tank cap.

 

What a guy ! :blueangel:

 

Thanks for the help.. vettdvr :flag :flag :flag

 

That procedure is straight from the shop manual.

Just one CAUTION, only turn the drain plug 90 degrees counterclockwise to open. After this you can pull it out. If you turn past this, you will be buying another drain valve (experience talking here).

 

Will the coolant drain on the radiator allow the block & heater to drain as well or sould I add clean water to the surge tank and run the engine then drain again until it runs clear? How many times should I repeat the process if it is necessary. My car has under 24000 miles but it is a 2000 and I doubt the coolant has ever been changed. I added a bottle of redline water wetter as a precaution until I do the change. Thanks for your help :thumbs:

 

Here's the flushing procedure:

Flushing

Important
Do not use a chemical flush.

Store used coolant in the proper manner, such as in a used engine coolant holding tank. 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. However, always remove the thermostat before back flushing the system.


Block the drive wheels.
Place the transmission in park (P) or neutral (N).
Engage the park brake.
Run the engine until the thermostat opens.
Stop the engine.
Follow the drain and fill procedure using only clean drinkable water. Repeat the procedure if necessary, until the fluid is nearly colorless. Refer to Draining and Filling Cooling System .
Fill the coolant reservoir to the FULL HOT mark.
Fill the cooling system. Refer to Draining and Filling Cooling System .

 

shop manual says only flush if coolant is dirty. My coolant was okay, so I just refilled. Plus I drained out to within 1 1/2 quarts of capacity.

 

Thanks guys Ill do the drain first and check the color like you suggest. Since it is the 5 year stuff I dont expect any problems. I just like to change it every 2 years. Kind of a habit from the old green stuff. :steering:

 

Wow, the guy has a memory like a service manual!!! :chevy ;)