What engine coolant on Volkswagen T2 and T3 engines?

As most classic enthousiast will know the 1.6 and 2.0 LBX engines are air cooled. Therefore they do not have a radiator or coolant. This article is aimed at the Volkswagen T2 and T3 owners with water cooled engines. The WBX Petrol engines and the diesel engines are water cooled engines. The best thing to use for cooling the engines is of course engine coolant. Water is in theory possible, but this will cause more problems with corrosion and less lubrication for your water pump. So go for coolant! Depending on the engine you will need about 16 to 18 liters of fluid. The reason that it is so much is that the radiator is in front of the car and the engine in the rear. That means the coolant has to travel for long distances.

The best coolant to use is G11 and G12+. It is NOT advisable to mix different types of coolant because they have different chemicals.  It is important to use the right coolant to prevent corrosion and blocking in the engine, radiator and heater. It will also increase your water pump lifespan because of better lubrication and prevent freezing in the wintertime.

How to fill your engine and bleed the air from the system

First you have to drain your cooling system as much as possible. Try to measure or estimate the amount of fluid you are taking out. This way you know if you have drained all the fluid or not. When the system is empty and connected back together you are almost ready to put in your new coolant.

Follow these steps to add your new coolant:

  1. Remove the radiator cover in the front of your van. This is where your headlights are and it can be removed by turning the screws to the left by a quarter. You can not unscrew them because they are not really screws.
  2. When the cover has been removed you will see a bolt on the top left of your radiator. Loosen this one a little, but you don’t have to take it out completely. This bolt is used to bleed the air out of the system when you start filling it again.
  3. Remove your engine cover (if it is still there) and find your heater pump in the left rear of the engine bay. There is a little screw on top of it that you can turn to the left by hand. This will also bleed the air out of the heating system which is connected to the engine cooling system.
  4. Now you can add coolant to both of the coolant tanks on the left front of your engine bay. Add as much as the engine will take without overflowing. Count the amount of liters that you are putting inside. You will probably have to start the engine a few times and rev it up to pump the coolant through the system. 
  5. Put the cap back on the coolant containers when you think the system is full.
  6. Set your heater to hot and open it up completely.
  7. Now put the nose of your car up about 40 cm by putting it on a jack, steep road or some other way. This is needed to make sure the air flows to the highest level, where the bleeding bolt is.
  8. Start your engine and rev your engine to about 2000 RPM by using a clip in the engine bay or letting a friend help you. Remove the cap of the right coolant container and start adding more and more coolant. Check at the top left of your radiator if there are air bubbles coming out. As long as there are bubbles coming out and not just coolant there is still air in the system and room for more coolant. When there is only coolant coming from the bleeder screw you can switch off the engine and put the cap on your cooling tank. Don’t forget to fill it till the max line on the container. Don’t worry about some coolant dripping over and causing a little smoke around your radiator.
  9. With the engine running, feel if your radiator is getting warm evenly so you know the water is flowing around in your cars system.
  10. Shut down the engine and let it sit for some minutes. Start it again and look at your radiator bleeder. Still no air coming from the radiator? Then you have successfully added new coolant and bleeded the system.
  11. Close the bleeding screw on the radiator and on the heater pump in the engine bay. Put the radiator cover back on and you are ready to go.

Never put more coolant in the system than the max line indicates on the coolant container! There is always soms ’empty’ room in the coolant containers because of pressure relief.