I am a Snap-On tool dealer, and I have been selling a product for about a
year or two now that will solve everybody's air entrapment problem. A lot
of the newer cars are experiencing this same problem because many of the
manufactures have eliminated the radiator cap and have not installed air
bleeds into the systems, the worst are Honda's. The products name is
Airlift by U/VIEW. There is a new lower priced unit called Airlift II that
is made out of plastic instead of brass like the more pricey unit, but will
work just as well. Both units run on shop air, and work by initially
creating a vacuum inside the cooling system and then you stick the units
hose into a container filled with your cooling mixture and open a valve.
The tool works. They should be available from most any mobile tool truck
dealer or any of the larger automotive tool wholesalers, the lower priced
unit goes for about a hundred bucks.

Mark Lally

P.S. if you can absolutely not find it locally, e-mail me and I will see
about getting you one.