OMC Parts Drawing *Cobra *Mercruiser *Alpha SEI Outdrives
Johnson outboard V4 lower unit
4 cylinder 90-degree outboard SEI aftermarket replacement small gearcase assembly years 1978 to 1998
Updated April 26 2026
- V4 crossflow 20 inch years 1988 – 1998
- V4 crossflow 25 inch years 1988 – 1991
- 100 hp. commercial 20 inch small hub years 1992 – 1997
- 120/140 hp. 20 inch years 1988 – 1994
- 120 hp 25 inch years 1988 – 1994
- 125 ESX years 1989 – 1991
- 125 ESX Club Nautico years 1992 – 1994
Johnson outboard V4 lower unit
Lower unit
Shafts are available that clip into lower units for 20 and 25 inch transoms 20 and 25 inch Johnson transoms if required.
If reusing the old shaft you will have to disassemble your old unit and remove the pin that’s holds the shaft in place.
Please see upper drive shaft page for new shafts.
28880 Complete gearcase V4
P/N 28210
Complete replacement outboard – Evinrude gearcase for OMC V4 lower unit gear ratio of 2:1 teeth 13:26
OEM 5000356
$2099.00 US
$2623.00 Cdn
Top side rear view
V4 90 degree small gearcase assembly years 1978 to 1998
Physical Characteristics are: 19-3/16 inch tall.
Cavitation plate to propeller shaft 7-1/4 inch.
Hub area is 4-1/8 inch.
Straight at the trailing end of the gear housing and the fin.
Pointed at the trailing end of the cavitation plate.
Six holes above the cavitation plate.
Internal water intake screen has four holes.
No pitot.