6B - 10 - CLOSED COOLING MODELS
90-816462 2-695
Cleaning System
Closed Cooling Section
Closed cooling section of the cooling system should
be cleaned at least once every two years or whenever
decreased cooling efficiency is experienced.
A good grade automotive cooling system cleaning so-
lution may be used to remove rust, scale or other for-
eign material. Always follow manufacturer’s instruc-
tions for the cleaner.
If closed cooling section is extremely dirty, a pressure
flushing device may be used to flush out remaining
deposits. Flushing should be done in direction oppo-
site normal coolant flow to allow water to get behind
deposits and force them out. Refer to instructions
which accompany flushing device for proper hookup
and flushing procedure.
NOTICE
For information and procedures for draining and
flushing seawater section of cooling system, refer
to SECTION 1B. For Cold Weather Or Extended
Storage, refer to SECTION 1B.
Seawater Section
Cooling efficiency of an engine with closed cooling is
greatly dependent upon heat transfer through the
tubes within the heat exchanger. During engine oper-
ation, contaminants within the seawater (such as salt,
silt, lime, etc.) collect on the inside of the tubes, thus
reducing heat transfer and greatly decreasing heat
exchanger efficiency. It is, therefore, recommended
that the seawater section of the heat exchanger be
cleaned at least once every two years or whenever
decreased cooling efficiency is suspected, as follows:
IMPORTANT: It may be necessary to remove heat
exchanger on some models. If heat exchanger is
removed, be sure to refill closed cooling section
with coolant.
1. Remove seawater drain plug from bottom of heat
exchanger and allow water to drain. After water
has drained completely, coat threads of drain plug
with Quicksilver Perfect Seal and reinstall.
2. Remove bolts which secure end plate to each end
of heat exchanger, then remove end plates, seal
washers and gaskets. Discard seal washers and
gaskets. Clean gasket material from end plate
and heat exchanger.
73581
b
a
71515
c
e
d
b
a - Bolt
b - End Cap
c - Sealing Washer
d - Gasket
e - Drain Plug
3. Clean water passages in heat exchanger by in-
serting a suitable size wire brush into each pas-
sage. Use compressed air to blow loose particles
out of water passages.
4. Apply Quicksilver Perfect Seal to both sides of
new end plate gaskets, then reinstall end plates,
using new gaskets and seal washers. (Be sure to
install seal washers between end plates and gas-
kets.) Torque end plate bolts to specifications.
Summary of Contents for 13
Page 1: ...13 Printed in U S A 90 816462 2 695 1995 Brunswick Corporation GM 4 Cylinder MARINE ENGINES ...
Page 2: ...90 816462 2 695 0 ...
Page 7: ...1 A IMPORTANT INFORMATION GENERAL INFORMATION 72000 ...
Page 15: ...1 B 50617 IMPORTANT INFORMATION MAINTENANCE ...
Page 36: ...1 C IMPORTANT INFORMATION TROUBLESHOOTING ...
Page 74: ...2 A 50633 REMOVAL AND INSTALLATION 4 CYL ALPHA ONE DRIVE ...
Page 88: ...3 A 26790 ENGINE 181 CID 3 0L 4 CYLINDER GM ENGINE ...
Page 137: ...4 A 72079 ELECTRICAL SYSTEMS STARTING SYSTEM ...
Page 170: ...4 B 71855 ELECTRICAL SYSTEMS IGNITION SYSTEM ...
Page 197: ...ELECTRICAL SYSTEMS CHARGING SYSTEM 4 C 72078 ...
Page 237: ...4 D 72747 ELECTRICAL SYSTEMS INSTRUMENTATION ...
Page 250: ...4 E 72938 ELECTRICAL SYSTEMS WIRING DIAGRAMS ...
Page 264: ...5 A FUEL SYSTEM FUEL PUMP ...
Page 271: ...5 B 72681 FUEL SYSTEM MERCARB 2 BARREL CARBURETOR ...
Page 300: ...6 A 50628 COOLING SYSTEM SEAWATER COOLED MODELS ...
Page 309: ...6 B 73665 COOLING SYSTEM CLOSED COOLING MODELS ...
Page 325: ...C 6 EXHAUST SYSTEM MANIFOLD ...
Page 331: ...7 A 71317 POWER STEERING PUMP ...