cooling YAMAHA TTR90 2000 Owners Manual

6 - 8
–+ELEC

CARBURETOR HEATING SYSTEM

The thermo switch circuit is open.
õ
The thermo switch circuit is closed.
Test step Water temperatureContinu-
ity
1Less than 23
±
3 ˚C
(73.4
±
5.4 ˚F)YES
2More than 23
±
3 ˚C
(73.4
±
5.4 ˚F)NO
3More than 12
±
4 ˚C
(53.6
±
7.2 ˚F)NO
4Less than 12
±
4 ˚C
(53.6
±
7.2 ˚F)YES
Test steps 1 & 2: Heating phase
Test steps 3 & 4: Cooling phase
l
Check the thermo switch operation.
WARNING
lHandle the thermo switch with special
care.
lNever subject the thermo switch to
strong shocks. If the thermo switch is
dropped, replace it.
CARBURETOR HEATER INSPECTION
1. Inspect:

l
Carburetor heater resistance
Out of specification
®
Replace.
Tester (+) probe
®

carburetor heater terminal
1
Tester (–) probe
®
carburetor heater body
2
Carburetor heater resistance:
6 ~ 10
W
at 20 ˚C (68 ˚F)