I just replaced my upper door gasket on my Tarm solo40. I couldn't get it to seal. I removed the bolt holding the door spring clip or whatever it's called and noticed it's worn out to about half its thickness. This causes the door to have less closing tension. The worn area can't be seen from the outside. Its where the door latch rubs against it. I was really surprised to see the amount of wear. That would cause the door to loosen up. Anyone with the Tarm ought to check it out.