Pre-1988 Mariner Outboard Lower Unit Gearcase Seal
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Sealing the gear oil inside the gearcase, and keeping water from intruding into the gearcase are the two aims of all the shaft seals, O-rings, spaghetti seals and gaskets in a lower unit. When you check your gear oil as a part of regular inspection, if you find the oil to be milky, it means water has been introduced somewhere. A seal kit and fresh gear oil will put you back in the safe zone. Need other parts? If you need parts not listed in the application guide, please see: |
Model | Serial Code | Serial No. Range | Lower Unit Seal Kit |
---|---|---|---|
2A | 646 | Obsolete | |
2B (M) | 6A1 | 000101 - 008800 | Obsolete |
2B (M) | 6A1 | 008801 - 115871 | 27-96338M |
2B (M) | 6A1 | 131232 & up | Obsolete |
3.5 | 642 | Obsolete | |
4A (M) | 6E0 | 001011 & up | 27-96324M |
4A (ML) | 6E0 | 300101 & up | 27-96324M |
5A | 661 | Obsolete | |
5C (M) | 6E3 | 102151 & up | 27-96324M |
5C (ML) | 6E3 | 400101 & up | 27-96324M |
6C (M) | 6H8 | 000317 & up | Obsolete |
6C (ML) | 6H8 | 300171 & up | Obsolete |
6D (M) | 6H6 | 001302 & up | Obsolete |
6D (ML) | 6H6 | 300406 & up | Obsolete |
8A | 655 | Obsolete | |
8B (M) | 677 | 000101 & up | 27-84172M |
8B (ML) | 677 | 300101 & up | 27-84172M |
8C (M) | 6G1 | 007990 & up | Obsolete |
8C (ML) | 6G1 | 305951 & up | Obsolete |
8C (MUL) | 6G1 | 700388 & up | Obsolete |
9.9C (M) | 682 | 000551 - 023105 | Obsolete |
9.9C (ML) | 682 | 300826 - 328485 | Obsolete |
9.9C (E) | 682 | 250101 - 250800 | Obsolete |
9.9C (EL) | 682 | 550141 - 551715 | Obsolete |
9.9C (M) | 682 | 023106 & up | Obsolete |
9.9C (ML) | 682 | 328486 & up | Obsolete |
9.9C (E) | 682 | 250801 & up | Obsolete |
9.9C (EL) | 682 | 551716 & up | Obsolete |
15A | 651 | Obsolete | |
15C (M) | 684 | 000101 - 013275 | Obsolete |
15C (ML) | 684 | 300101 - 312685 | Obsolete |
15C (E) | 684 | 250101 - 250805 | Obsolete |
15C (EL) | 684 | 550101 - 551255 | Obsolete |
15C (M) | 684 | 013276 & up | Obsolete |
15C (ML) | 684 | 312686 & up | Obsolete |
15C (E) | 684 | 250806 & up | Obsolete |
15C (EL) | 684 | 551256 & up | Obsolete |
20A | 653 | Obsolete | |
20C (M) | 6A9 | 000101 - 010111 | 27-41899M |
20C (ML) | 6A9 | 300101 - 306542 | 27-41899M |
20C (E) | 6A9 | 250101 - 250819 | 27-41899M |
20C (EL) | 6A9 | 550101 - 550693 | 27-41899M |
20C (M) | 6A9 | 010112 & up | |
20C (ML) | 6A9 | 306543 & up | |
20C (E) | 6A9 | 250820 & up | |
20C (EL) | 6A9 | 550694 & up | |
25A | 648 | Obsolete | |
25C (M) | 695 | 000101 - 023895 | 27-41899M |
25C (ML) | 695 | 300101 - 318173 | 27-41899M |
25C (E) | 695 | 250101 - 253861 | 27-41899M |
25C (EL) | 695 | 550101 - 555959 | 27-41899M |
25C (M) | 695 | 023896 & up | |
25C (ML) | 695 | 318174 & up | |
25C (E) | 695 | 253862 & up | |
25C (EL) | 695 | 555960 & up | |
28 | 664 | Obsolete | |
30A (M) | 689 | 000366 - 022058 | 27-41899M |
30A (ML) | 689 | 301911 - 3213767 | 27-41899M |
30A (E) | 689 | 100251 - 105324 | 27-41899M |
30A (EL) | 689 | 401216 - 411946 | 27-41899M |
30A (M) | 689 | 022059 & up | |
30A (ML) | 689 | 321377 & up | |
30A (E) | 689 | 105325 & up | |
30A (EL) | 689 | 411947 & up | |
40A | 676 | Obsolete | |
40B (M) | 676 | B000106 & up | 27-94533M |
40B (ML) | 676 | B300101 & up | 27-94533M |
40B (E) | 676 | B100461 & up | 27-94533M |
40B (EL) | 676 | B400420 & up | 27-94533M |
40C (M) | 6E9 | 000106 & up | 27-94533M |
40C (ML) | 6E9 | 300126 & up | 27-94533M |
40C (E) | 6E9 | 100101 & up | 27-94533M |
40C (EL) | 6E9 | 400231 & up | 27-94533M |
48 | 670 | Obsolete | |
W-48 (M) | 670 | 002161 & up | Obsolete |
W-48 (ML) | 670 | 311996 & up | Obsolete |
55 (M) | 663 | Below - 02730 | Obsolete |
55 (ML) | 663 | Below - 34925 | Obsolete |
55 (M) | 663 | 02731 & up | Obsolete |
55 (ML) | 663 | 34926 & up | Obsolete |
55 (E) | 663 | 004041 & up | Obsolete |
55 (EL) | 663 | 315379 & up | Obsolete |
W55 (ML) | 663 | 578278 & up | Obsolete |
60 (E) | 675 | 00101 - 001170 | Obsolete |
60 (EL) | 675 | 30101 - 304180 | Obsolete |
60 (E) | 675 | 001171 & up | Obsolete |
60 (EL) | 675 | 304181 & up | Obsolete |
60 (E) | 6F0 | 000101 & up | Obsolete |
60 (EL) | 6F0 | 300311 & up | Obsolete |