No cabin airflow after short drive

Change the cabin air filter - RockAuto.com shows six of them - - http://www.youtube.com/watch?v=bBOxtAgUuKE

the racket is the blower going bonkers after the bearings heat up and its not really spinning much at all ,just rattleing to anoy you

That could be the cause Jimmy. It is old enough to wear out the bushings. Probably some leaves and branches in there too.

More back ground This has been going on since last June. When the car is started cold the fans and heat or AC work normal. After ten to 15 mins, airflow drops way off. Seems like more of a ducting then a fan problem. Are there some valves in the ductwork out of position? Where's the cabin air filter? Behind glove box?

The video in the first post shows how to change the filter. --- It could be a problem with the blend doors. Those are the vacuum operated devices that send air in various areas. There should be one door that recirculates cabin air or allows outside air to enter. Maybe you have something like a squirrel nest blocking the ducts. --- When you say the fan makes a lot of noise, does it sound like it's wobbling or is it just spinning and not pushing air?

Thanks Awesome The fan sounds OK, I think I'm hearing air noise. Ever heard of old vacuum lines collapsing on these cars?

Usually the vacuum hoses get brittle and crack. Sometimes they leak more when cold or hot. It depends on the type of hose,the size, the radius of the bend and the vacuum.