60
              
            
            
              
                5.2.2 DRIVE CHAIN TENSION AND ALIGNMENT
              
            
            
              A roller chain transmits rotational power to the
            
            
              roller.  It must be kept properly tensioned and
            
            
              the sprockets aligned to obtain the expected
            
            
              performance and life.
            
            
              To check the tension and alignment, follow this
            
            
              procedure:
            
            
              1. Clear the area of bystanders, especially
            
            
              small children.
            
            
              2. Turn machine off, stop engine, remove ig-
            
            
              nition key and place in pocket and wait for
            
            
              all moving parts to stop.
            
            
              3. Remove panel over chain.
            
            
              4. The chain should be snug to be properly
            
            
              tensioned.
            
            
              5. 
            
            
              
                To adjust chain tension:
              
            
            
              a. Loosen idler mounting bolts.
            
            
              b. Move the idler to the required position
            
            
              to set chain tension.
            
            
              c. Set sprocket alignment.
            
            
              d. Tighten mounting bolt to its specifed
            
            
              torque.
            
            
              6. 
            
            
              
                To replace chain:
              
            
            
              a. Move idler to its loosest position.
            
            
              b. Replace chain.
            
            
              c. Set sprocket alignment.
            
            
              d. Tighten idler mounting bolt to its speci-
            
            
              fed torque.
            
            
              e. 
            
            
              
                Check frequently during the frst ten
              
            
            
              
                hours and set chain tension as re-
              
            
            
              
                quired.
              
            
            
              7. Lay a straight edge across the sprocket
            
            
              faces to check alignment.  Adjust align-
            
            
              ment if sprocket faces vary more than 1/32
            
            
              inch (.7 mm).
            
            
              
                Fig.  64    CHAIN DRIVE SYSTEM / IDLER
              
            
            
              
                Fig.  65    SPROCKET ALIGNMENT