Onan MJA Series Service Manual page 25

_ _
23 COOLING SYSTEM
tem, Fig.3.1. E. The closed water system continuously recirculates
water through the engine water jacket, expansion tank, exhaust manifold,
centrifugal pump, and one side of the heat exchanger. The raw water
system uses the engine-mounted, rubber-impeller pump to draw sea
or city water and circulate it through the heat exchanger, then discharges
the water.
CAUTION: When planning to install any brand of heat exchanger other
than ONAN approved, or any keel cooler, consult the factory
or an ONAN distributor. To insure an adequate installation,
the engine COOling system must be modified.
( LATE. )
MODELS
..... RAW WATER
RAW COOLING WATER ~"""'"
WATER IN CLOSED SYSTEM
EXHAUST
MANIFO.D
CYLINDER BLOCK
CONNECTION
E:3
WATER IN ClOSED SYSTEM
( EARLY)
MODELS
FROM SOURCE
HEAl EXCHANGER
ENGINE
MOUNTED
PUMP
RAW COOLING
WATER FROM
.SOURC£
EXPANSION TANK
\::=:jJ)jJ
•
1- - \
RAW WATER
CENTRIFUGAL PUMP
FIG 3.1.E - PICTORIAL MlC HEAT EXCHANGER COOLING SYSTEM