Hello Akasha,
Sounds like you have to get a bit more serious with it, to get it moving.
Here are some things to try.

Spray some Penetrene in the rusted joint, it is a rust penetrating oil.
Spray the joint and leave it do its work for a while.

Disconnect the linkage at the back so you can get more movement on the pedal. (you don't want to damage the cone or clutch plates either)

The pedal rod does have some travel in and out of that tube, try knocking it in and then out from underneath, with a hammer and brass drift / iron rod, what ever you have.

You will have to drop the cutting deck all the way down to get at it with a long bar, like a jack handle maybe from underneath.

Then try twisting the pedal to try and get it moving. Get some more spray into the joint.
You have to do all this, with out breaking or damaging it of course. So feel your way.

If that doesn't work, you can heat and cool the joint with an oxy or gas torch, then repeat above.
Good luck. Let us all know how you go.
Mark

Last edited by mark electric; 04/12/14 03:12 PM.

Happy is he who penetrates the mystery of things.