Subaru IMPREZA 2002 Service Manual page 240

WATER PUMP
COOLING
22) Connect the battery ground cable.
23) Fill coolant. <Ref. to CO-25, FILLING OF EN-
GINE COOLANT, REPLACEMENT, Engine Cool-
ant.>
C: INSPECTION
1) Check the water pump bearing for smooth rota-
tion.
2) Check the water pump pulley for abnormalities.
3) Using a dial gauge, measure impeller runout in
thrust direction while rotating the pulley.
"Thrust" runout limit:
0.5 mm (0.020 in)
I
4) Check the clearance between impeller and
pump case.
Clearance between impeller and pump case:
Standard
Limit
0.5
-
0.7 mm (0.020
-
0.028 in)
1.0 mm (0.039 in)
5) After water pump installation, check pulley shaft
for engine coolant leaks. If leaks are noted, replace
the water pump assembly.
CO-34