I have what is becoming an old bag-less vacuum that was losing suction and cleaning power due to poor canister mating with the main vacuum body. It was obvious the leaks were coming from the airway connection areas as I could feel the air blowing out through the connections.
After looking for a seal that would be simple, hold, and is cheap, I decided to use pieces of Heavy Duty Duck (formally called Duct) Tape from my closet. I cut approximately 1/4″ inch strips off the tape and applied it around the mouth of the canister airway connections. Some sides of the connections took more tape than the other sides. Go slow and do not overdo the tape layer, or it may cause a worse air leak than the tape fixes.
I spent about fifteen minutes taping the airway connection areas. Most of this time went to the tape sticking to the scissors. Vacuum has improved 100%, and remains strong. If in the future, the vacuum starts to lose vacuum, it is simple to identify the leak areas and add tape.
Perhaps I used maybe three inches total, so if you don’t have any tape, I am sure you can ask someone if you can have a few inches of their tape. The beater brush is still worn out, but I don’t have a cheap fix for that. All in all, I spent ten minutes and ten cents making a large improvement to an old vacuum. Save yourself money and try a simple fix first.