Operation; Water Cooling System - BOMBARDIER Johnson 90 Service Manual

POWER UNIT
OPERATION
OPERATION
Water Cooling System
The water cooling system includes the lower unit water pump, lower unit to power unit water supply tube,
oil pan water pressure valve, power unit water passages and thermostat. This system cools both the
power unit and exhaust and is shown in schematic from below. lf overheating occurs, the components of
the cooling system must be inspected for blockage, corrosion buildup or component damage.
Component inspection Refer to page
Water pump / lmpeller 9-10
Water tube . . . . . . . . . . . . . . .
7-6
Thermostat. . . . . . . . . . . . . . . 6-66
Water pressure valve . . . . . . . 7-20
Cylinder head. . . . . . . . . . . . . 6-24
Cylinder block . . . . . . . . . . . . 6-46
RETURNHOSE
When open
THERMOSTAT
CYLINDER HEAD
CYLINDER
CRANKCASE
INTAKE MANIFOLD
ENGINE HOLDER
EXHAUST WATER
JACKET
FUEL RETURN PIPE
ENGINE HOLDER
PILOT WATER HOLE
OILPAN OILPAN
PRESSURE VALVE
DRIVESHAFT HOUSING WATERTUBE
WATER PUMP
PROPELLER EXHAUST
OUTLET
WATER INTAKE
WATER
6-67