coolant flush procedure
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
Re: coolant flush procedure (lotzahp)
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 .
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.
Park the vehicle on a level surface.
Remove the surge tank cap:
Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Place a drain pan under the drain fowl.
Open the radiator drain fowl.
Allow the cooling system to drain completely.
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.
Close the radiator drain fowl. Tighten
Tighten the radiator drain fowl to 2 N·m (18 lb in).
Fill the cooling system through the surge tank.
Fill the cooling system with a 50/50 mixture of DEX-COOL® coolant and deionized water.
Start the engine.
Allow the engine to idle for 1 minute.
Install surge tank cap.
Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant temperature reaches 99°C (210°F).
Shut off the engine.
Remove the surge tank cap.
Start the engine.
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.
Install the surge tank cap.
Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant reaches 99°C (210°F).
Shut off the engine.
Remove the surge tank cap.
Top off the coolant as necessary, 12.7 mm (0.5 in) above FULL COLD mark on the surge tank.
Rinse away any excess coolant from the engine and the engine compartment.
Inspect the concentration of the engine coolant.
Install the surge tank cap.
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 .
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.
Park the vehicle on a level surface.
Remove the surge tank cap:
Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Place a drain pan under the drain fowl.
Open the radiator drain fowl.
Allow the cooling system to drain completely.
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.
Close the radiator drain fowl. Tighten
Tighten the radiator drain fowl to 2 N·m (18 lb in).
Fill the cooling system through the surge tank.
Fill the cooling system with a 50/50 mixture of DEX-COOL® coolant and deionized water.
Start the engine.
Allow the engine to idle for 1 minute.
Install surge tank cap.
Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant temperature reaches 99°C (210°F).
Shut off the engine.
Remove the surge tank cap.
Start the engine.
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.
Install the surge tank cap.
Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant reaches 99°C (210°F).
Shut off the engine.
Remove the surge tank cap.
Top off the coolant as necessary, 12.7 mm (0.5 in) above FULL COLD mark on the surge tank.
Rinse away any excess coolant from the engine and the engine compartment.
Inspect the concentration of the engine coolant.
Install the surge tank cap.
Le Mans Master
Joined: Jan 2001
Posts: 5,008
Likes: 508
From: Hilton NY
Re: coolant flush procedure (MSBHVN)
When I changed the thermostat I found that the entire system can be flushed when the thermostat is unbolted; by covering different hoses and engine block thermostat openings with your hand and moving the garden hose to different positions all the old coolant will be flushed without starting the engine. I used tap water for refill because I have seen corrosion in equipment at work caused by ion hungry deionized water.
