imo46

How do i bleed Cooling System ?

beep-beep

if you want to remove air pockets - drive around and add G12 (RED!!!) coolant into the expantion tannk.

If you put green coolant and now you want to replace it with the red one or something this severe, you cannot do it at home. You probubly better go to the place with coolant flushing equipment and let them handle it for ~$50.

RangeR BoB

From the timing belt tech article:
https://www.audiworld.com/tech/eng42.shtml


58) Make a 50%/50% mixture of antifreeze and distilled water. (A third gallon container is needed for this.)

59) Loosen the 2nd bleeder screw, located on the U shaped black metal coolant pipe, which runs around the base of the intake manifold (snakey thing). It is a metal hex socket head bolt, facing up, near the rear right of the engine. Do not remove it, just loosen it 3 turns.

60) Slowly refill the cooling system at the overflow tank, until coolant dribbles out of the 2nd bleeder screw. Close the 2nd bleeder screw. Continue filling until coolant dribbles out of the heater hose bleed screw. Close the bleeder screw. Fill the overflow tank to the full cold line.

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71) With the coolant tank cap off, start the engine. Turn OFF the Auto-climate control system (set the fan speed to the lowest setting, then release and push the "-" fan speed button once more) so that the radiator fans don't run (for the AC), and the heater is off. (Manual AC/Heat control : set the fan to OFF, temp to cool, AC OFF.) Let it idle until the engine temp gauge reads normal operating temp. Do not rev the engine as it warms up, as the water pump bearing/seals may not be well lubricated until the thermostat opens and purges out the trapped air that may be in the pump. Once the engine has reached normal operating temp, rev the engine a few times (2500 RPM) to purge any remaining air pockets. Recheck the coolant level, and then tighten the coolant tank cap so the system can pressurize. Let the engine continue to idle until the radiator cooling fan comes ON. Let it idle for a few more minutes, then shut off. Check for leaks. Recheck the coolant level when the engine has cooled back down to room temp. Check underneath for coolant leaks.<ul><li><a href="https://www.audiworld.com/tech/eng42.shtml">Audiworld link</a></li></ul>