My Vanagon 85' won't make any heat! I have tried all I can think off
I have bleeded it by the book, checked hoses, cleaned the system, 
But nothing. I have an aux. heater in the back that makes a little
heat
And only a little heat!!! 
It's like the water pump doesn't make the water flow to the heater.
The water pump isn't an original pump is there a difference??
But the motor doesn't get to hot how come???

Any ides???
Thanks Jesper