Cummins ISX15 Air in Coolant Problem

The repair was done in some official Cummins center. I assume they checked it but no info about it.
Tomorrow will conduct the coolant pulsation test with transducer and ocilloscope. Will get back with results

 

Tomorrow I will conduct a test with a pressure sensor (transducer) and ocilloscope to check if there are some pulses and if they are correlated with engine firing. If find the correlation I will remove fuel injectors to chech combustion chamber with camera.

 

I was thinking about it but never did concidering that after it rest during the night it wasn't bubbling until I start the engine. Then after 2-3 minutes it starts to bubble... Moreover I disconnected all 5 lines to external devices (both oungoing and incoming). Anyway will conduct this test if fail to find pulsation correlation with engine revs. THANK YOU!

 

I also noticed that it works this way. When I blow into the tube myself the liquid turned yellow very fast. Then I feed it from compressor and it turned back to blue - I was a bit surprised because on the web it is said that it is not supposed to. Next I feed it from the exhaust pipe of the same truck - turns yellow very fast. I assume it proves that the liquid works just fine.
No coolant ever went to the tube I checked that.

 

And yes, when I connect that already reacted yellow liquid to overflow valve of the cooling system the gases make it turn back blue..