It doesn't stay cocked.
Here it's how the shutter works and its workflow.
1.- We take down the cock lever.
2.- It spins as you take it down...
3.- Taking the shutter release level to its position handling the shutter ring blades.
4.- This number 4 should connect with a tab from N#2 and stay cocked.
5.- We press the shutter release level from outside.
6.- It transmits movement inside to the level N#4 which holds the open/close mechanism.
7.- The level moves to the right the shutter should open and close the blades according to the speed set (the rounded mechanism between 1 and 2 o'clock).
The problem is point N#4 It doesn't keep the cocking mechanism and the shutter is released without pulling N#5.