Alpha One lower unit gearcase housing exploded view drawing
Last updated on 09/20/2023
Mercruiser and Alpha One (up to 1990) exploded view lower unit parts drawing
Water pump components, impellers, seals, shafts and gear sets
Manufactured by GLM, California. All parts include a 2 year warranty
Easy to identify photos with OEM Mercury numbers
Mercruiser Alpha 1 Gen 2 lower unit
Upper Housing
Description
OEM number
Price
(USD)
Price
(Canadian)
SEI Mercruiser Alpha 1 Gen 2 lower unit
Item 1 SEI SE116 Aftermarket SEI lower unit Mercruiser Alpha One Gen 2 aftermarket lower unit. For 1991 and up models only, serial numbers OD470000-Up, For 4 cylinder, V6 and V8 models up to 300 horsepower. Will not replace 2.00 or 2.40 ratio units.
$1199.99
$1599.99
85590 Face seal
#2 Face seal 26-816575A2
$4.95
$6.95
89630 Mercruiser water pump impeller
#3 Impeller 47-43026T2
$15.95
$20.95
31240 Gasket
#4 Gasket 27-817277-1
$4.95
$5.95
12500 Face plate
#5 Face plate 817276-1
$6.95
$8.95
30090 Gasket
#6 Gasket 27-43033-1
$4.95
$6.95
81390 O-ring
#7 O-ring 25-90011
$4.95
$6.95
85011 Oil seal
#8 Oil seal 26-66302
$8.95
$11.95
23200 Mercruiser Retainer
#9 Retainer 824519-1
$4.95
$6.95
21580 Roller bearing
#10 Roller bearing (1991-1997) 31-36387A1
$40.95
$53.95
21584 Roller bearing
#10 Roller bearing (1998 & up) 31-33138A1
$41.95
$54.95
23210 Shim
#11 Shim 15-42637A1
$16.95
$21.95
11140 Drive shaft
#12 Drive shaft 45-816919
$529.95
$699.95
85581 Oil seal
#13 Oil seal 26-816464-1
$7.95
$9.95
81175 O-ring
#14 O-ring 25-896522
$4.95
$6.95
85140 Seal
#15 Seal 26-45577-1
$4.95
$6.95
31170 Gasket
#16 Washer 12-19183-3
$4.95
$6.95
21731 Draining Screw
#17 Screw 22-8M0058389
$4.95
$6.95
21610 Pinion bearing
#18 Roller bearing 31-42647A1
$35.95
$46.95
11091 Alpha 1 Gen 2 Forward gear set
#19 Forward gear set (1991-95)
$629.95
$831.95
11092 Alpha1 Gen2 Forward gear set
#19 Forward gear set (1996-up) 43-878087A2
$686.95
$906.95
32800 Washer
#20 32800 Washer
$4.95
$6.95
11190 Pinion nut
#21 Pinion nut 11-35921
$4.95
$6.95
12710 Trim tab anode
#22 Trim tab anode 76214Q5
$16.95
$21.95
11040 Shift crank
#23 Shift crank 76865
$67.95
$89.95
11030 Mercruiser Alpha 1 Gen 2 Shift spool
#24 Shift spool 818349T1
$86.95
$114.95
23220 Mercruiser Shim
#25 Shim (1991-95) 3.500 O.D. 15-47397A1
$11.95
$15.95
23221 Alpha 1 Gen 2 Shim
#25 Shim (1996-up) 3.265 O.D. 15-44491A1
$5.95
$7.95
21590 Bearing
#26 Bearing (1.875 I.D./3.500 O.D.) 31-35928T1
$59.95
$78.95
21591 Mercruiser Bearing
#26 Bearing (1.750 I.D./3.500 O.D.) 31-828437A2
$115.95
$152.95
21593 Bearing
#26 Bearing (1.875 I.D./3.265 O.D.) 31-828439A2
$128.95
$169.95
21820 Bearing
#26 Bearing (1.750 I.D./3.265 O.D.) 31-30894A1
$35.95
$46.95
11420 Roller bearing
#27 Roller bearing 31-30895T
$14.95
$19.95
11050 Spring
#28 Spring 24-30893
$4.95
$6.95
21131 Cross pin
#29 Cross pin 17-8M0020941
$4.95
$6.95
11060 Clutch
#30 Clutch 52-853594T
$225.95
$297.95
11155 Alpha 1 Gen 2 Prop shaft
#31 Prop shaft 43-850308
$660.95
$871.95
11013 Mercruiser Reverse gear
#32 Mercruiser Reverse gear 43-828073A1
$250.95
$330.95
23140 Thrust ring
#33 Thrust ring 68100-1
$11.95
$15.95
21620 Ball bearing
#34 Ball bearing 30-88957T
$37.95
$49.95
83445 O-ring
#35 O-ring 25-896524
$4.95
$6.95
11410 Roller bearing
#36 Roller bearing 31-30956T
$9.95
$12.95
85130 Oil seal
#37 Oil seal 26-14077
$7.95
$9.95
85700 Oil seal
#38 Oil seal 26-12224
$12.95
$16.95
11381 Tab washer
#39 Tab washer 14-18323
$14.95
$19.95
21120 Cover nut
#40 Cover nut 8M2011027
$18.95
$24.95
21301 Thrust hub
#41 Thrust hub 12-835467Q01
$21.95
$28.95
21760 Lock washer
#42 Lock washer 13-42351-1
$4.95
$6.95
21360 Tab washer receiver
#43 Tab washer receiver 12-31211Q03
$6.95
$8.95
21200 Tab washer
#44 Tab washer 14-816629Q
$4.95
$6.95
21250 Prop nut kit
#45 Nut 11-52707Q1
$8.95
$11.95
11405 Bearing carrier
#46 Bearing carrier 818763A10
$157.95
$207.95
21031 Mercruiser Alpha 1 Gen 2 Lower shift shaft
#47 Mercruiser Alpha 1 Gen 2 Lower shift shaft 815919A1