Had the same problem and fixed it by replacing clutch cable as it was old,and had to use a piece of wood and a hammer to release the arm(hitting down on it)Worked the actuating arm back and forth ,cleaning around pivot and using lots of wd40 as above.Worked well.......but now 1 year later problem is back.So I am going to do the same again.
Recurring problem I think.
Jay g, December 2009