Engine Cooling; Radiator Pressure Cap; Water Pump— Typical L6 - Chevrolet 10 1971 Series Chassis Service Manual

G e n e r a l D e s c r i p t i o n .........................................................................
M a in te n a n ce and A d ju s tm e n ts
C o o lan t L e v e l ................................................................................
C o o la n t System C hecks .............................................................
P e rio d ic M a i n t e n a n c e .................................................................
C le an in g ....................................................................................
R e v e rs e F l u s h i n g .....................................................................
R a d i a t o r ....................................................................................
All Chevrolet trucks have pressure type engine cooling
systems with thermostatic control of coolant circulation.
The cooling system is sealed by a pressure type radiator
filler cap.
The pressure type radiator filler cap (fig. 1) is de­
signed to operate the cooling system at higher than at-
Fig. 1— Radiator Pressure Cap
Fig. 2— Water Pump— Typical L6
SECTION 6K

ENGINE COOLING

Page
6K-1
. . .............................................. 6K-2
6K-2
6K-2
6K-2
6K-3
6K-3
6K-3
GENERAL DESCRIPTION
INDEX
C y lin d e r B lo c k and C y lin d e r H e a d ...............................
H ot W ate r H eate r C o r e .....................................................
F an B e lt A d ju s t m e n t .....................................................................
T h e rm o sta t ....................................................................................
R e p la c e m e n t ................................................................................
W ate r P u m p ....................................................................................
R e m o v a l ....................................................................................
I n s t a lla t io n .....................................................................
mospheric pressure. The higher pressure raises the
boiling point of the coolant which increases the efficiency
of the radiator.
The radiator filler cap contains a pressure relief
valve and a vacuum relief valve. The pressure relief
valve is held against its seat by a spring which when
compressed, allows excessive pressure to be relieved
out the radiator overflow.
The vacuum valve is also held against its seat by a
spring which when compressed, opens the valve relieving
the vacuum created when the system cools off.
The cooling system's water pump is of the centrifugal
vane impeller type (figs. 2 and 3). The bearings are per­
manently lubricated during manufacture and are sealed to
prevent the loss of lubricant or the entry of dirt and
water. The pump requires no care other than to make
certain the air vent at the top of the housing and the drain
holes in the bottom do not become plugged with dirt or
grease.
Page
6K-3
6K-3
6K-3
6K-3
6K-3
6K-4
6K-4
. . 6K-4
10-30 CHEVROLET TRUCK SERVICE MANUAL