Komatsu PW130ES-6K Operation & Maintenance Manual page 225

SERVICE PROCEDURE
Tighten the lock nut to 24 N.m and re-check the valve lash
Mark the pulley and rotate the crankshaft 360° degrees.
Be sure timing pin is sisengaged, before rotating.
The timing pin will not engage in this position. With the engine in
this position, check and adjust the following valve clearances.
Intake (I) cylinders: 3,4
Exhaust (E) cylinders: 2,4
Tighten the lock nut to 24 N.m and re-check the valve lash.
Install the valve covers and tighten capscrews to 24 N.m
CHECK FAN BELT TENSIONER BEARING BELT
AND FAN HUB
Check the tensioner bearing
G
With the fan belt removed rotate fan hub.
The tensioner pulley should spin freely with no rough spots
defected under hand pressure.
Check the tensioner bearing.
G
Replace bearing if damaged.
G
Check fan hub. With the drive belt removed, rotate fan hub.
G
NOTE: The fan hub should spin freely without excessive end
play.
Check the fan hub bearing.
G
Replace bearing if damaged.
G
CHECK FAN BELT TENSION
Measure the belt deflection at the longest span of the belt.
G
Maximum deflection: 9.5-12,7 mm
G
If tension is low (deflection is outside range): (see "Check fan
belt tensioner bearing, belt and fan hub.")
Check belt & replace if damaged.
G
Check tensioner & replace if damaged.
G
224
MAINTENANCE.