Very hard to turn wheel steering on a 1987 Pearson 27

Apr 7, 2011
38
1989 catalina 27 Pearson 1987 milford
My P27 is equipped an outboard rudder controlled with a standard Edson wheel assembly which drives a converter box via two flex cables. The converter box has a lever arm which extends out the stern and drives the rudder via a 2 foot long rectangular bar. Has anyone serviced or have any info of , what I'm calling, this converter box. It's bolted to the interior of the stern. I'm planning to disassemble the converter to determine why it's so very hard to move. The problem may also be in a section of the two drive cables , which are encased in a what appears to be a BX outer sheath.
Thanks
Chris