D7C brake sticking

My D7 s/n 17A 5563, brake has been sticking for a year or so, works fine, just have to push pedal hard and pull it back by hand, seems worse after machine is up to operating temperature. I have looked inside brake compartment, sprayed all pivot points , seemed to look normal. This is on the right side sitting on the seat.

Probably worn shaft/bushing of the brake pedal. This allows dirt/rust to build up and cause the sticking. Take the pedal off and just clean it up for a temporary fix. 
Craig 

I have unhooked the pedal mechanism and lubed it and it moves free, problem must be inside the housing so where.

The parts book I have is for D7D 17A11,879 to 19,442 Sorry. Maybe Old Magnet or someone else on the forum will help.
Good luck,
Craig

It seems to be stuck where the pedal rod goes through the steering clutch housing