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Yamaha Outboard Lower Gearcase Parts Diagram

The diagram below is applicable for the following models:

  • 40 HP (1984-87)
  • 50 HP (1984-87)
Mercury Outboard Lower Gearcase Diagram - 35 thru 70 HPMercury Outboard Lower Gearcase Diagram - 35 thru 70 HP
RefDescriptionPart #ReplacesQty
1Water pump housing bolt-97395-08055-002
2Water pump housing washer-92990-08600-004
3Water pump housing-663-44311-02-001
4Water pump insertSIERRA-18-3435663-44322-00-001
5ImpellerSIERRA-18-30686H4-44352-02-001
6Wear plate to water pump gasketSIERRA-18-0292663-44315-A0-001
7Water pump wear plateSIERRA-18-3436663-44323-00-001
8Wear plate to water pump gasketSIERRA-18-0294663-44324-A0-001
9Water pump base-663-44341-00-941
10Pump base gasket-663-44316-A0-001
11Pump base o-ringSIERRA-18-029893210-41042-001
12Pump base oil sealSIERRA-18-029793101-23070-002
13Water pump housing boltSIERRA-18-025697095-08045-002
14Water pump repair kitSIERRA-18-34296H4-W0078-00-001
15Water seal-663-44366-00-001
16Tapered roller bearing-93332-00079-001
17Drive shaft (short)-6H4-45501-00-001
17Drive shaft (long)-6H4-45501-10-011
18Shim (0.05mm)-663-45587-00-05AR
Shim (0.08mm)-663-45587-00-08AR
Shim (0.12mm)-663-45587-01-12AR
Shim (0.30mm)-663-45587-01-30AR
Shim (0.50mm)-663-45587-01-50AR
19Drive shaft sleeve-6H4-45536-00-001
20Needle bearing-93315-32224-001
21Bearing (up to 1987)-663-45552-00-001
22Pinion gear-6H4-45551-00-001
23Pinion gear nut-90170-12138-001
24Woodruff keySIERRA-18-330590280-03024-001
25Gearcase seal kitSIERRA-18-27926H4-W0001-20-001
26Plate bolt-97095-06016-001
27Plate washer-92990-06600-001
28Plate-6H4-45321-01-001
29Plate o-ring-93210-49046-001
30Shift cam assembly (short shaft-6H4-44150-01-001
Shift cam assembly (long shaft-6H4-44150-12-011
31Bearing housing o-ringSIERRA-18-029993210-66M98-001
32Vent plug-90340-08M04-002
33Dowel pin-93604-08062-002
34Drain plug gasket-90430-08020-003
35Nylock nut-90185-05904-001
36Water inlet cover (starboard)-688-45215-02-001
37Locking washer-92990-10100-004
38Bolt-97079-10040-004
39Ball bearing-93306-00702-001
40Drain plugSIERRA-18-2374688-45341-00-001
-Propeller-Various1
42Trim tab bolt-97575-08675-001
43Lower casing-6H4-45301-01-EK1
44Locking washer-92990-08100-001
45Lower casing bolt-97095-08085-001
46Trim tabSIERRA-18-6906A664-45371-01-001
47Rubber seal-688-45375-00-001
48Rubber seal guide-663-45376-00-941
49Oval head screw-98780-05535-001
50Water inlet cover (port)-668-45214-02-001
51Forward gear shim (0.05mm)-6H4-45567-00-05AR
Forward gear shim (0.08mm)-6H4-45567-00-08AR
Forward gear shim (0.12mm)-6H4-45567-01-12AR
Forward gear shim (0.30mm)-6H4-45567-01-30AR
Forward gear shim (0.50mm)-6H4-45567-01-50AR
52Tapered roller bearing-93332-000V4-001
53Forward gear-6H4-45560-00-001
54Cross pin (clutch dog)-90250-06023-001
55Sliding clutch-663-45631-01-001
56Cross pin retaining ring-663-45633-00-001
57Shift plunger-676-45635-00-001
58Shift slide-663-45634-00-001
59Compression spring-60501-16M01-001
60Propeller shaft-679-45611-01-001
61Plate washer-90201-22429-001
62Reverse gear-6H4-45571-00-001
63Reverse gear shim (0.05mm)-663-45577-00-05AR
Reverse gear shim (0.08mm)-663-45577-00-08AR
Reverse gear shim (0.12mm)-663-45577-01-12AR
Reverse gear shim (0.30mm)-663-45577-01-30AR
Reverse gear shim (0.50mm)-663-45577-01-50AR
64Thrust washer-663-45576-00-001
65Cotter pinSIERRA-18-238091490-30030-001
66Castle nutSIERRA-18-373290171-16011-111
67Washer-92990-16200-001
68Prop mounting spacer (aft)-670-45997-02-001
69Prop mounting spacer (fore)-663-45987-02-001
70Cover nut-697-45385-00-001
71Tab washer-90214-48M03-001
27Bearing housing oil sealSIERRA-18-029693101-22067-002
73Needle bearing-93317-2204-001
74Bearing housing key-90282-04010-001
75Bearing housing-679-45331-00-941

Sorry, is not an active item in our system. However, we may still be able to help you. Please email us at rajeshk@klizer.com or call us at (866)388-0390 for assistance. Please make sure to have the item number handy when you contact us.

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