Volkswagen Repair: 2001 Volkswagon beetle overheating, air flow sensor, volkswagon beetle

Question
Hello there, I am writing to you to ask about my 2001 volkswagon beetle, it's having troulbe overheating and I can not figure it out. I have had it in the repair shop and the guy told me I didn't have a cracked head or gasket. he found that the flange was onces wracked and the owner before me had put liquid glass in it to seal it up, so we replaced it and I have also replaced the air flow sensor, the thermostat and the flange sensor, along with the radiator, still I am haveing overheating problems with it. the motot size is a 2.0  I have also took the thermostat out once and tryed to run it like that, then once I tried to bypass it with the heater core and still its overheating.  and one other thing I need to know if both fans are to run at the same time to cool it down too.
                            thank you leann

Answer
Hi Leann;
Did you feel the back of the water pump when you replaced the thermostat?  It's only a possibility at this point.  The biggest issue you are up against now is....I'll bet you did not use a vacuum to refill the cooling system.  All Volkswagens REQUIRE a 1.5 atmosphere vacuum to be pulled into the entire cooling system before refilling with fresh coolant.  The only tool I know of available in the aftermarket is called  "AIRLIFT"  and they are about $250.00 just for the tool, but it has to be done, or else there are air bubbles, and air pockets that are never removed from the system, and the car will continue to overheat.  You've got to find one, and use it.  That's the only way.  Sorry.  Wish I had easier, better news.  Good luck, Leann.  I hope you get the right tool, and get the car fixed.