A quick search revealed that it is very common for the sealing strips to wear out, and replacement parts are readily available. The whole process of replacement should take about $15 and 15 minutes of your time.
This post was first published here.
Step 1: Tools/Materials
-small long-nose pliers
-small needle-nose pliers
You will need to order a new heating element and some Teflon tape. I got mine from Elements and More for about $15 (and free shipping). Be sure to tell them to write "Do Not Bend" on the mailing envelope. You could probably use NiChrome wire or ribbon for a more DIY approach.
Step 2: Disassemble
Once it's opened up, you get to see all of the cool guts, like the huge transformer and the vacuum pump.
Step 3: Remove Old Components
Push the old Teflon tape through the side hole and grab it from the other side with pliers to remove. The old heating element should then come out easily. Scrape away any melted thermoplastic or other burned material that may be stuck to the machine.