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Old 11-15-2012, 01:57 PM
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dc_wright dc_wright is online now
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Mein Auto: '06 Z4 3.0si, '11 128CiC
Unfortunately steps 4 and 5 of your bleeding process are incorrect. You do not run the engine and bring it up to temperature. If you re-read your Bentley manual where it directs to start the engine is AFTER you have run sufficient coolant to complete the bleeding process (no air bubbles coming out), replaced the bleed screw, and replaced the reservoir cap.
When you are adding coolant to do the bleeding process you do not "fill the reservoir up quickly", it must be done deliberately and very slowly otherwise you get more air entrapment.

How to bleed your radiator (m20/m50)

1. Start when the car is cold.
2. Open the rad cap and bleed screw (m20 engines have an extra one on the thermostat housing).
3. Fill up water into the expansion tank quickly until it runs out of both bleed holes. At that point fill up slowly (just to save water) until all the bubbles seem to have run out from both holes, then stop pouring.
4. Start the engine and set cabin heat to high. Blower does not need to be activated.
5. Let the car reach operating temperature ...might take you up to 10 minutes.
2006 Z4 3.0si Sport Package (But I'll still hang with my "homies" in the E36 forum)

Last edited by dc_wright; 11-15-2012 at 01:59 PM.
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