Bleeding the coolant tank

[jst2878]

What is the proper procedure on bleeding the expansion tank after replacing the system with new antifreeze?

[Bimmer360]

sjt2878, try the following steps:

- Loosen the screw on the tank
- set temp in pass to full warm, then set blower to low settings turn ON, not start engine.
- add coolant/distilled water into the tank until it bleeds from bleed screw until its free of air bubbles.
- tighten screw and replace cap

Then, Run engine until it reach operating temp, re-check coolant tank and top off if necessary.

[jst2878]

thanks

[dkl]

My question is...how do you add coolant to the radiator when all you have access to is the expansion tank? Is there another filler access point that I'm not seeing?

[jst2878]

you add coolant to the expansion tank....That fills the radiator.

[flyingmachine]

Originally Posted by Bimmer360

sjt2878, try the following steps:

- Loosen the screw on the tank
- set temp in pass to full warm, then set blower to low settings turn ON, not start engine.
- add coolant/distilled water into the tank until it bleeds from bleed screw until its free of air bubbles.
- tighten screw and replace cap

Then, Run engine until it reach operating temp, re-check coolant tank and top off if necessary.

If you drained coolant from engine block, this procedure doesn't seem to properly vent the air trapped inside block. Because if you don't run the engine, coolant will not become warm enough and thermostat close the passage to the engine until coolant temperature reaches to some point.