Mercury 40 Service Manual page 421

4. Lift impeller, drive key, and gasket. Replace im-
peller if:
– Impeller blades are cracked, torn, or worn.
– Impeller is glazed or melted (caused by insuffi-
cient water supply).
– Rubber portion of impeller is not bonded to im-
peller hub.
a - Impeller
b - Drive Key
c - Gasket
5. Remove plate and gasket.
6. Replace plate if groove(s) (other than impeller
sealing groove) in plate are more than .030 in.
(.762mm) deep.
a - Plate
b - Gasket
Old Style Base
7. Remove water pump base by lifting gently as
shown. Inspect carefully for cracks.
a - Water Pump Base
90-852572R1 JANUARY 1998
a
c
b
51207
a
b
51206
a
51206
New Style Base
8. Remove water pump base by lifting gently as
shown. Inspect carefully for cracks.
a
a - Water Pump Base
9. Remove (and discard) seals, if damaged.
a
a - Seals
10. Remove seal and plate if damaged or worn.
a
b
a - Seal
b - Plate
55874
51205
51268
LOWER UNIT - 6B-13