Quote Originally Posted by 36 sedan View Post
The small recovery tank (tube type along side my radiator) did not have enough capacity to maintain a proper level in the radiator. On hot days (100° +) the radiator would purge more than the tank could hold, then on cool down after the radiator recovered what was in the tank, it would pull air in.

The additional catch can adds ample space for full recovery and no more air problems.
Quote Originally Posted by 36 sedan View Post
Absolutely correct, unless your way cool chrome hot rod recovery tank is too small as mine was.

Not trying to tell anyone what to do, just sharing what I did to correct my problem in hopes it will help some others.

Sorry for the confusion.
What I'm saying is that even with a relatively small tank (mine measures 2"OD x 17" tall) one can purge the air and have a cushion of fluid in reserve.