Mercury 45 Jet 50-55 - Gear Housing Disassembly; Water Pump

LOWER UNIT - 6A-790-817643R1 DECEMBER 1996
Gear Housing Disassembly
Water Pump
1. If water tube seal (a) stayed on water tube (inside of dri-
veshaft housing) when gear housing was removed,
then pull seal from water tube. Replace water tube seal
(a) if damaged.
2. Remove 6 bolts (b), washers (c) and isolators (d) (De-
sign 1). Remove cover (e).
NOTE: Isolators (d) from forward 2 screws are different
from the other isolators. Retain these for proper re-assem-
bly (Design 1).
IMPORTANT: The circular groove formed by the impel-
ler sealing bead should be disregarded when inspect-
ing cover and plate as the depth of the groove will not
affect water pump output.
3. Replace cover if thickness of steel at the discharge
slots is .060 in. (1.524mm) or less, or if groove(s) (other
than impeller sealing groove) in cover roof are more
than .030 in. (.762mm) deep.
51206
a
b
b
b
c
c
c
c
d
d
e
4. Lift impeller (a), drive key (b), and gasket (c). Replace
impeller if:
– Impeller blades are cracked, torn, or worn.
– Impeller is glazed or melted (caused by insufficient
water supply).
– Rubber portion of impeller is not bonded to impeller
hub.
51207
a
b
c
5. Remove plate (a) and gasket (b).
6. Replace plate if groove(s) (other than impeller sealing
groove) in plate are more than .030 in. (.762mm) deep.
51206
a
b
7. Remove water pump base (a) by lifting gently as
shown.
51206
a