I should also add that the tension dial needs to be assembled correctly, and sometimes the felt disc is hardened or missing. It is a simple dial: felt disc or discs go on first. Then the big disc with the slot in it with the "saucer" facing OUT. Then the slotted washer. Then the spring. Then the nut. I added one felt disc to my machine, reassembled it correctly, and my top tension problems are gone.