Hi there:

I tried to flush the coolant of 2004 MPV. I ran into problems.
This is what I have done.
1. remove the cooling system cap. (Note that there is only one cap on the reservoir. The radiator itself has no other cap.)
2. remove the drain plug and drain the coolant.
3. Close the plug.
4. refill the coolant to the reservoir.

Now the problem comes. The coolant I add does not flow back to the radiator.
After the reservoir reaches to the "F", the coolant flows out from the overflow pipe. I have drained out about 3.5L of coolant. I can't even add one drop back to the radiator. Please help. Thanks in advance.

 

Well, after sitting there for one hour, it starts slowly flow back to the radiator.
It works now.

 

I know this is a little late but I had the same problem, what happens when you drain all the water/antifreeze out, since theirs no fluid in the water pump it does not create a suction to pull or push fluids thru to the radiator. What I ended up doing is disconnected the top hose and put antifreeze thru there with the car on, it only needs little to primer the pump then just connect it back and add the rest thru the reservoir tank make sure you check the level for the next few days.