Exactly right 'red coupe' there must be 'free play ' in the system. Free play is determined by pulling the pedal all the way back, then slowly (using hand pressure) push pedal towards disengagement, as soon as resistance is felt measure how far pedal was moved from the starting point. That is 'free play' As pedal is pushed to full disengagement it should sudddenly get easy near the end of the travel. That is 'over center', you have reached max disengagement, set pedal stop to that point, so you don't over extend the diaphragm spring.