pump truck paul,

I have enclosed a nice picture of the parking brake. The little item called the 'brake lock' has to have rather sharp edges where the pedal arm passes through it. These sharp edges bite into the arm and hold it, which holds the parking brake ON!

See if the picture helps and take a look at the condition of this 'brake lock'. Good luck.

http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0506.htm

Stuart