Log in Sign up
Cart

Alpha One® Gen I Sterndrive Complete - 1972-1990 | SEI SE106

$1,755.00

Shipping calculated at checkout.

Alpha One® Gen I Sterndrive Complete - 1972-1990 | SEI SE106

Sterndrive Engineering Alpha One® Gen I Sterndrive Complete Replacement Sterndrive(Replaces Mercruiser's Alpha One) | SE106

  • Alpha One® Gen I Sterndrive Complete
  • Replaces most Mercruiser Sterndrives 228 HP and up from 1972-1990.
  • Ships in two boxes. Comes with a 9-9/16 new style input yoke.
  • Does not include Complete Install Kit or Anode Kit. Please see related items below.
  • Up to 300 HP (SEI does not warranty applications over 300 HP)
  • Replaces Mercruiser Sterndrive 225-S 1974, Replaces Mercruiser Sterndrive 233 1975-1977, Replaces Mercruiser Sterndrive 250 1977, Replaces Mercruiser Sterndrive 260 1978-1982, Replaces Mercruiser Sterndrive 898/228 1977-1982, Replaces Mercruiser Sterndrive R/MR/Alpha One 1983-1990
  • Typical Mercruiser Sterndrive engine liter applications from 1983-1990 include 5.7L, 5.0L (4 barrel carb) | Typical Mercruiser Sterndrive engine cubic inch applications from 1983-1990 include 350, 305 (4 barrel carb) | Typical Mercruiser Sterndrive engine horsepower applications include 260, 230, 228
Additional Information
  1. Replacesmost Mercruiser Sterndrives from 120 -260 HP 1967-1990
  2. YourMercruiser Sterndrive must have trim and tilt to be able to use our replacement drive.
  3. Ifyour Mercruiser Sterndrive is between 1967-1969 you must verify that you have 13 splines on your upper driveshaft .
  4. Shipsin two boxes. Comes with 9 -9/16 input yoke.
  5. Doesnot include Complete Install Kit or Anode Kit. Please see related items below.
  6. Todetermine if you have a counter rotation unit on your twin engine boat it is easiest to look at the props.

If the props are identical orientation, then they are both standards. If the prop blades are opposite, then the port should be a counter rotation

  1. Pleaserefer to the model chart below to find your proper Mercruiser Sterndrive Replacement.

These are typical applications, it is best to confirm your ratio by counting the teeth in the upper. Although great care was taken in the creation of this guide, SEI cannot guarantee its accuracy.

Model

Year Range

Serial Range

Notes

See Below

Complete Std. Rotation

Upper

All

Lower Std. Rotation

Complete Counter Rotation

Lower Counter Rotation

120/140

1967-1969

2062141-2791956

1,2,3,4,5,6

1.94

See #1

See #1

1.94 C.R.

See #1

120/140

1970-1982

2791957-6225576

2,4,5,6

1.94

1.94

Lower

1.94 C.R.

Lower C.R.

160

1967-1969

2065190-2763441

1,2,3,4,5,6

1.62

See #1

See #1

1.62 C.R.

See #1

165

1970-1977

2763442 and up

2,4,5,6

1.62

1.62

Lower

1.62 C.R.

Lower C.R.

225 -S

1974

3856268-4200499

4,5,6

1.47

1.47

Lower

1.47 C.R.

Lower C.R.

233

1975-1977

4200500

4,5,6

1.47

1.47

Lower

1.47 C.R.

Lower C.R.

250

1977

4791300-4898729

4,5,6

1.47

1.47

Lower

1.47 C.R.

Lower C.R.

260

1978-1982

4898730-6225576

4,5,6

1.47

1.47

Lower

1.47 C.R.

Lower C.R.

470

1976-1982

4208730-6225576

2,4,5,6

1.81

1.81

Lower

1.81 C.R.

Lower C.R.

485

1980-1982

4893835 and up

2,4,5,6

1.81

1.81

Lower

1.81 C.R.

Lower C.R.

888

1971-1977

3106717 and up

4,5,6

1.47

1.47

Lower

1.47 C.R.

Lower C.R.

898/228

1977-1982

4782330-622576

4,5,6

1.47

1.47

Lower

1.47 C.R.

Lower C.R.

R/MR/Alpha

One

1983-1990

6225577-OD469858

6,7

Notes

  1. Unit has an 8 spline driveshaft on the lower unit. If your unit is original, you need to purchase a complete.
  2. Unit has a short yoke on the upper driveshaft. We refer to this as the “Old Style”

***Applies to all inline 4 and inline six cylinder engines up until and including 1982***

  1. Unit must have trim and tilt for our Replacement to work. If it has two trim hoses going to each cylinder, it has trim and tilt.
  2. Unit has an eyelet on top cover. Replacement unit will not.
  3. Unit has a round cavitation plate on lower unit. Replacement unit will not.
  4. Unit may have an o-ring and/or a preload pin on lower unit driveshaft. The replacement will not.
  5. GearRatio must be confirmed. Chart below is typical applications, however there is no guarantee it is correct.

To be safe it is best to remove the top cover and count the teeth on the upper gears.

Engine

Configuration

Horsepower

Gear Ratio

Tooth

Count

Complete Std. Rotation

Upper

All

Lower Std. Rotation

Complete Counter Rotation

Lower Counter

Rotation

Inline 4 Cyl.

2.5L/3.0L

120/140

1.98/1.94

20/24

1.94

1.94

Lower

1.94 C.R.

Lower C.R.

Inline 4 Cyl.

3.7L

170

1.84/1.81

17/19

1.81

1.81

Lower

1.81 C.R.

Lower C.R.

Inline 6 cyl

160/165

1.65/1.62

24/24

1.62

1.62

Lower

1.62 C.R.

Lower C.R.

V6 4.3L

185/190

1.84/1.81

17/19

1.81

1.81

Lower

1.81 C.R.

Lower C.R.

V8 305 2

Barrel Carb.

200

1.65/1.62

24/24

1.62

1.62

Lower

1.62 C.R.

Lower C.R.

V8 305/350

230/260

1.50/1.47

20/22

1.47

1.47

Lower

1.47 C.R.

Lower C.R.

V8 454 7.4L

330

1.32*/1.29*

20/16

*Gear ratio not available. You could substitute a 1.47 ratio, but it would not be covered

under our 3 year warranty as it is over our 300 HP Limit


Brunswick Corporation is the Original Equipment Manufacturer (OEM). Sterndrive Engineering, Inc. (or SEI) has no affiliation with the Brunswick Corporation. Sterndrive Engineering, Inc. manufactures a stern drive designed to replace Mercury Marines MerCruiser, Alpha One, R, MR, and Gen II stern drives. MerCruiser, Alpha One, Gen II, R, and MR are trademarks of the Brunswick Corporation. As with any after-market product, any warranties governing products manufactured and/or sold by Brunswick Corporation will not apply to products manufactured and/or sold by Sterndrive Engineering, Inc. (or SEI) or to products damaged due to the operation of an SEI product.

Go to full site