I n s t a l l Water Manifold
1. With new gaskets in place, lower the
water manifold down over the studs and
secure it to the cylinder head with two
nuts and lock washer at each riser.
Tighten the nuts to 25-30 lb-ft (34-41
Nm) torque.
2. Install the temperature gage adaptor
i n the end of the manifold.
3. Attach the thermostat housing and
outlet elbow to the water manifold with
bolts and lock washers.
Figure 11F-9. Water Manifold
4. Fill cooling system to the proper
Mounting
level.
1. Drain the cooling system to level nec-
essary by opening the valve in the bot-
THERMOSTAT
tom of the fresh water pump and the
valve in the thermostat housing.
Description
2. Loosen the bolts which secure the out-
let elbow and the thermostat housing to
The temperature of the engine coolant is
the water manifold.
automatically controlled by a thermostat
located in a housing connected to the
3. Remove the cooling water temperature
outlet end of the water manifold. A
gage adaptor from the rear end of the
blocking type thermostat Figure 11F-10
water manifold.
is used.
4. Remove the water manifold stud nuts
and lock washers and lift the manifold
Operation
straight up off the studs. Remove the
manifold to cylinder head gaskets.
At coolant temperatures below approxi-
mately 160 to 17OF (71 to 77C), the
thermostat valves remain closed and
block the flow of coolant to the radiator.
During this period, all of the coolant in
the standard system is circulated
through out the engine and is directed
back to the suction side of the water
pump via the bypass tube. As the cool-
ant temperature rises above 160 to
170F (71 to 77) the thermostat valves
start to open, restricting the bypass
system, and permit a portion of the cool-
ant to circulate through the radiator.
When the coolant temperature reaches
approximately
185
to
195F
(85
to
91C) the thermostat valves are fully
open, the bypass system is partially
blocked off, and most of the coolant is
directed through the radiator.
A properly operating thermostat is es-
sential for efficient operation of the en-
gine.
If
the
engine
operating
F i g u r e 11F-10. Thermostat Housing
temperature deviates from the normal
Mounting
range of 160 to 185F (71 to 85C) or
170 to 195F (77 to 91C), remove the
thermostat and check it.