SEI Mercury Replacement Outdrives, Uppers and Lowers - Mercury Outboards

Replaces most Mercury 3&4 Cylinder 2-Stroke 1987 and newer 70-125 HP
Also replaces most 75-115 HP 4-Stroke below Serial #OT801000.
This unit will not replace a 3 jaw lower unit unless you also change the shift shaft in the midsection.

The SE 206 gear case replaces most Mercury 2.0, 2.4 and
2.5 liter gear cases with 4-3/4 Bullet Diameter.\

SE216
Replaces Most Mercury 3.0L Lower Units
13 Splines
20, 25, and 30 inch Shafts.
If you have an 8 Spline drive shaft you will need to buy the stub shaft unit
and purchase an upper driveshaft from an OE dealer.
20" 45-824114A 1
25" 45-823901A 1
30" 45-824115A 1 (This item is no longer available from the OE. You will need to source a used one, or fix your old drive.)
If you have a 13 spline two piece shaft just purchase the appropriate
one piece shaft.
The SEI 216 gear cases are supplied with the correct water tube coupling for units with a serial number of OG438000 and higher. If your unit has a lower serial number, you will need to use your old water coupling or purchase the correct part (SEI part number 96-116-12K).

SE218 Counter Rotation
Replaces Most Mercury 3.0L Counter Rotation Lower Units
Do not use for standard rotation
13 Splines
25 and 30 inch Shafts.
If you have an 8 Spline drive shaft you will need to buy the stub shaft unit
and purchase an upper driveshaft from an OE dealer.
25" 45-823901A 1
30" 45-824115A 1 (This shaft is no longer available from the OE. You will need to either source a used one or repair your old unit.)