1979 Johnson 2HP Outboards Service Manual, Page 46Get this manual
6-5 GEARCASE PRESSURE TEST test gearcase sealing, proceed as follows1Remove drain plug and screw in pressure test gaugeSee Figure 6-13Stevens Experimental pressure test gauge il1ustrated2pressure to 3-6 pounds (21-42 kPa)Gearcase must hold 3-6 pounds (21-42 kPa)If pressure gauge indicates leakage, submerge gearcase in water to determine source of leakage as evidenced bubblesIf gearcase pressure gauge does not indicate leakage, increase pressure to 16-18 pounds (110-124 kPa)Pressure should also hold at 16-18 pounds (110-124 kPa)If pressure does not hold, submerge gearcase in water and check for source of leakageMake necessary repairs and repeat testGearcase must hold within the range of 3-6 pounds (21-42 kPa) pressure 12 131
REASSEMBLY AND INSTALLATION OF EXHAUST HOUSING
If removed install vibration dampeners
Figure 6-13Gearcase Pressure Test
Install grommet and water tube in top end of housingSee Figure 6-12Attach housing to swivel bracket and tighten clamp screws to 60-80 inlbs (7.0-9.0 Nm)dUsing new gasket, install power head