HI there 
1st if the belt between the crank & the cam shafts broke there is a 99% chance that the valves have bent and possable damage to the cylinder head the car wont start 
 
2nd the cut out at the rear of the cam shaft is the timing alignment  you insert a bar between the cam and the cyl head it can only go one way to ensure correct tdc no 1 piston
                
 TONY ...FORD TECHNICIAN
                
 January 2005