I have no experience with the Crary Air reel but a lot of hard learned practice from building and operating a small seeds vacumn harvester for many years using nothing but air to lift and transport the material.[ a 400hp cat engine was needed to drive it!] Air has weight [ 1.225 Kg's _ cubic metre] and inertia and does some very strange things including going straight past out lets that any body would assume that it will go down. On our R62 combine, we had a similar experience as yours in a home made 30 ft air duct that used a full length, 5mm wide slot instead of tubes to blow material into the header. To check the air distribution along the duct, drill 1_16 th holes every couple of feet and use a water manometer; A length of small diameter clear plastic tube in a U shape attached to board. Each leg of the U should be about 3 feet long. Put water in the tube until the legs are half full. Place one end of the plastic tube hard against the drilled hole in the duct and measure the difference in the water levels in the tubes. This gives the air pressure at that point in the air duct. Repeat along the duct. Big variations will indicate air flow problems within the duct. How to fixIJIJ In your case I don't know except a try every thing approach. Using pitot tubes similar to those on aircraft, manometers can find all sorts of air flow problems and verify fixes in the separation areas of combines as well. This suggestion may not help but it does allow air pressure and distribution to be checked. Cheers!