How to drain all coolant and refill with a simple shop vacuum

[Domiac]

Here is a tip on how to completely flush / refill your cooling system using a simple shop vacuum.

To drain your system, first open both large and small tubes underneath the car, next to transmission and then connect a shop vacuum to the tubes to completely empty the system.

To flush your system, should you want to do it, connect your shop vacuum to each tube and use your hand to inspect where the suction is. Then pour 1 liter of clean battery water or such from a bottle into a tube where suction exists. Just make sure you do not suck any dirt or your gloves in the system.

To refill a completely drained system, first top off your coolant tank. You'll notice that you only get around half of the fluids in. Then connect shop vacuum to the larger tube underneath the car, next to transmission. Please watch your coolant level on the tank at the same time when you first activate your shop vacuum. You will see that the vacuum will suck level down pretty quick, only let the shop vacuum run for a second or so depending on how powerful vacuum you have. The point is to refill your coolant tank before the level drops too low and you get air in your system. Repeat this process of activating shop vacuum for a second and topping off your coolant tank as many times as you can. After around ten vacuum runs, you'll notice that you have filled over 20 liters to the system, still missing a few liters. Then open the clip on the coolant cap to relieve pressure, start the car, let the pump run and refill rest of the couple liters slowly, no CEL light or low coolant warnings should occur.

At least for me this trick worked fine and the whole process was easy.