Proper way of burping the coolant system?

rcnacura

US Spec 8V
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So I went and did a track day and my water temps went into the red alot. Car then did the warning to let the car idle. So if back of the throttle and then the temps would eventually go back to "normal", but as soon as I did some wot passes out will come up again.

I opened the coolant reservoir to release any air, but didn't really make a difference. Refilled, let it idle and air was releasing but still not much progress. Never had this happen before, but I did just take off some coolant hose to replace an oil line in the turbo last week.

Any tips/suggestions on how to properly get all the air out? Or if you think it might be another issue, please do let me know your thoughts. Tia

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Antifreeze should lift the boiling point of the cooling water way above 100°C anyway
 
There are no cooling system bleeders to allow air bleeding, and as a result no reliable way to purge air already in the system.

The workshop manual requires the system to be drained and then refilled under vacuum.

A technique I have found useful on other cars is to use a "zero pressure" radiator cap. By preventing pressurisng the system air bubbles will be larger so more likely to bubble out. You can easily make a zero pressure cap by removing the seal mechanism or drilling a hole through the cap.
 
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Having recently completing a GTD MK 7 timing belt replacement I purchased a vacuum filler

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Works perfectly by utilising compressed air rushing by a Venturi, this causes a vacuum in the coolant system (hoses collapse) you then can introduce fresh coolant by opening the system to air, this sucks in the coolant and refills the system in minutes, with no air locks.

Very quick and easy.....if you have a compressor.
 
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