MerCruiser R Drives Gear Housing Diagram

MerCruiser R Drives Gear Housing Diagram

Ref Part # Note Qty Description
- 1623-8951A43 1 Gear housing assembly - complete
1 1623-5356A4 1 Gear housing assembly
2 17-37972 1 1 Shift crank pin
3 16-46911 1 Stud (7/16-20 x 3-3/16”)
4 16-56298 2 Stud (7/16-20 x 1-31/32”)
5 26-45577 1 1,2 1 Seal
6 16-56297 2 1 Stud (5/16-24 x 3-3/8”)
7 16-69501 2 Stud (1/4-28 x 3-1/4”)
8 17-35973 2 Dowel pin
9 31-92366A1 1 Roller bearing
10 66885 1 Water pickup insert (starboard)
11 66884 1 Water pickup insert (port)
12 10-76156 1 Screw
13 11-45812 1 Nut
14 45-41939F 1 1 Driveshaft assembly
15 17-30545 1 Preload pin
16 24-34576 1 Spring
17 25-30613 1,2 1 Driveshaft o-ring
18 43-96084A7 1 Gear set (forward & pinion)
19 11-35921 1 Pinion nut
20 15-57007A1 AR Shim kit
21 31-53079A1 1 Tapered roller bearing assembly
22 27-856704 1,2 1 Gasket (water pump to gear housing)
23 25-33145 1,2 1 O-ring
24 46-57234A1 1 Water pump base assembly
25 26-89238 1 1 Oil seal
26 26-16977 1 1 Oil seal
27 17-35973 2 Dowel pin
28 27-85608 1 1,2 1 Lower gasket
29 32435 1 2 1 Face plate
30 27-858524 1,2 1 Upper gasket
31 46-96148T1 2 1 Water pump body assembly
32 48752T 2 1 Insert
33 26-38970 2 1 Water inlet tube seal
34 47-89984T4 2 1 Impeller
35 28-56654 1 Impeller key
36 10-30720 1 Screw
37 12-36001 1 Washer
38 11-826708 9 2 Nut (1/4-28)
39 11-826709111 1 Nut (5/16-24)
40 12-29245 3 Washer
41 25-30271 2 1 Rubber ring
42 23-29804T 2 1 Guide sleeve
43 77481 1 1 Lower shift shaft
44 53-29641 1 Retaining clip
45 12-27880 1 Washer
46 25-25439 1 1 O-ring
47 23-30617A2 1 1 Shift shaft bushing assembly
48 26-89236 1 1 1 Oil seal
49 12-31266 1 1 Rubber washer
50 12-29395 1 Shift shaft washer
51 10-79953Q2 1 Screw
52 12-19183 3 1,2 1 Washer
53 18-46950 1 Cotter pin
54 818349T1 1 Shift spool assembly
55 76865 1 Shift crank
56 15-47397A1 AR Shim kit
57 - 1 Forward gear (see #18)
58 31-30895T 1 Roller bearing
59 31-35928T1 1 Tapered roller bearing assembly
60 52-853594T 1 Sliding clutch
61 17-30632 1 Cross pin
62 24-30893 1 Spring
63 44-824110 1 Propeller shaft
64 43-92320T 1 Reverse gear
65 35915 1 Thrust ring
66 30-88957T 1 Ball bearing
67 15-97166 1 Shim
68 25-31534 1 1 O-ring
69 73020A14 1 Bearing carrier
70 31-30956T 1 Roller bearing
71 26-76868 1 2 Oil seal
72 28-30281 1 Key
73 14-79447 1 Tab washer
74 79448 1 Retainer ring
75 12-835467Q01 1 Thrust hub (use with Black Max props)
56292A4 1 Thrust hub (use with MC I props)
76 12-31211A3 1 Splined washer
77 14-816629 1 Tab washer
78 11-52707Q1 1 Propeller nut
79 31640Q4 1 Trim tab (2-3/8”)
34127T2 Opt Trim tab (4”)
80 10-32470 1 Trim tab screw
81 10-30206 1 Screw
82 11-34933 2 Nut
83 13-42351 1 1 Lockwasher
- 26-33144A2 - Gear housing seal kit
- 46-96148A8 - Water pump repair kit
- 43-803079T1 3 - Lower unit rebuild kit
- 31-803068T1 3 - Seal & bearing kit

Note 1: Contents of seal kit QS-26-33144A2
Note 2: Contents of water pump repair kit QS-46-96148A8
Note 3: Rebuild kit includes all gears, shims, bearings, seals, clutch & prop nut to rebuild lower unit
AR: As required