Checking The Thermostat; Installing The Thermostat - Yamaha YXR70FX Service Manual

3
2
LS
New
a
1
5 - 6
THERMOSTAT
EBS00132

CHECKING THE THERMOSTAT

1. Check:
• thermostat 1
Does not open at 50 ~ 54 °C (122 ~
129.2 °F) → Replace.
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a. Suspend the thermostat in a container filled
with water.
b. Slowly heat the water.
c. Place a thermometer in the water.
d. While stirring the water, observe the ther-
mostat and thermometer's indicated tem-
perature.
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1 Thermostat
2 Thermometer
3 Water
4 Container
È Fully closed
É Fully open
TIP:
_
If the accuracy of the thermostat is in doubt,
replace it. A faulty thermostat could cause seri-
ous overheating or overcooling.
2. Check:
• thermostat cover
• thermostat housing (cylinder head)
Cracks/damage → Replace.
EBS00133

INSTALLING THE THERMOSTAT

1. Install:
• thermostat 1
• O-ring 2
New
• thermostat cover 3
TIP:
_
Install the thermostat with its breather hole a
facing up.
2. Fill:
• cooling system
(with the specified amount of the recom-
mended coolant)
Refer to "CHANGING THE COOLANT" in
chapter 3.
3. Check:
• cooling system
Leak → Repair or replace any faulty part.
COOL
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