1964 Chevy Truck carb problems

See if a carb rebuild kit is available for the carb. If you pull the carb apart try to be careful when seperating the pieces due to gaskets and check balls once all has been disasembled use a good carb cleaner through all ports and passages and clean all dirt from bowls. Check to make shure float is adjusted correctly if you can purchase a carb kit for it the directions will show you have to set the float and go through the carb.