Subaru Impreza 2002 Service Manual page 194

TIMING BELT ASSEMBLY
MECHANICAL
3. BELT TENSION PULLEY
1) Check the mating surfaces of timing belt and
contact point of adjuster rod for abnormal wear or
scratches. Replace the belt tension pulley if faulty.
2) Check the belt tension pulley for smooth rota-
tion. Replace if noise or excessive play is noted.
3) Check the belt tension pulley for grease leakage.
4. BELT IDLER
1) Check the idler for smooth rotation. Replace if
noise or excessive play is noted.
2) Check the outer contacting surfaces of idler pul-
ley for abnormal wear and scratches.
3) Check the idler for grease leakage.
ME(STi)-55