Audi A1 Coolant Refill: 1.4 TDI Guide

Hello,
According to the repair manual, the coolant should be filled using a vacuum system. I bought a device from Stahlmaxx for this purpose and tested it with my small air compressor (6-liter tank) to see how much vacuum pressure I could generate. The compressor managed to create 0.6 bar of vacuum, but the pressure immediately dropped back down to 0.2 bar.
Ich dachte Kühlkreislauf hat ein Leck und habe mal mit der Handpumpe 1bar Druck auf das System gegeben. Die 1bar hat das System die ganze Nacht gehalten. So, no leak.

Does anyone know about something like this?

What other ways are there to fill the 1.4 TDI engine without introducing too many air bubbles?

I don't want to create another problem after replacing the turbocharger.
Sure, here's the translation:

"Thank you in advance..."

Hi there,
I fill it as usual according to the old method and bleed it at the highest point, even though Mr. Audi might write something different in the owner's manual. Perhaps that could also work with the 1.4 TDI engine.
hg
Herbert.

Malo wrote:

Hello, According to the repair manual, the coolant should be filled using a vacuum system. I bought a device from Stahlmaxx for this purpose and tested it with my small air compressor (6-liter tank) to see how much vacuum pressure I could generate. The compressor managed to create 0.6 bar of vacuum, but the pressure immediately dropped back down to 0.2 bar. Ich dachte Kühlkreislauf hat ein Leck und habe mal mit der Handpumpe 1bar Druck auf das System gegeben. Die 1bar hat das System die ganze Nacht gehalten. So, no leak. Does anyone know about something like this? What other ways are there to fill the 1.4 TDI engine without introducing too many air bubbles? I don't want to create another problem after replacing the turbocharger. Thank you in advance...

Hello,

Seals can behave in completely different ways under pressure and vacuum conditions, and are often designed based on the direction of the pressure gradient.

Best regards, Rainer.

"These are often designed based on the direction of the pressure gradient."

Then I would wonder why one should fill it with vacuum pressure according to the repair instructions.

"

Malo wrote:

"These are often also designed based on the direction of the pressure gradient." Then I would wonder why one should fill it with vacuum according to the repair instructions.

I'll leave that to your imagination.

The cooling system needs to be largely free of air, as Herbert wrote.
It must be airtight and not leak any coolant.

What do you think is missing?

"What do you think is missing?"
Please provide the text you would like me to translate from German to English. I will then give you only the translation, without any explanations.