Old lien a problem?

Update: the original lienholder is long out of business but a sucessor corporation signed a lien release.  Kudos to Western Skyways! 
 

Liens expire in a few years. This one is long dead. It may require a couple steps. Google removing an expired lien Washington state

has it been registered since then?

  I got the CD of records from FAA.  There's a $2,500 mortgage from 1967 never released, owed to a bank in Washington State.  I cannot find an FAA procedure to remove it/release it from their records. Is this going to be a problem when I sell? Who do I ask for help?