Coolant temperature gauge

Check

1 The circuit consists of the sender mounted in the thermostat housing under the fuel tank, and the gauge mounted in the instrument panel. If the gauge malfunctions, first check the coolant level (see Daily (pre-ride) checks). If the level is correct, check that the battery is fully charged and that the fuses are all good.

2 If the gauge is still not working, remove the fuel tank (see Chapter 4). Disconnect the wire from the sender and turn the ignition switch ON (see illustration).The temperature gauge needle should be on the 'C on the gauge. Now earth the sender wire on the engine. The needle should swing immediately over to the 'H' on the gauge. If the needle moves as described, the sender is defective and must be renewed. Caution: Do not earth the wire for any longer than is necessary to take the reading, or the gauge may be damaged.

Replacement

4See Chapter 9.

Temperature gauge sender

Check

5 Remove the fuel tank (see Chapter 4). The sender is mounted in the thermostat housing.

6 Disconnect the sender wiring connector (see illustration 5.2).Using a continuity tester, check for continuity between the sender body and earth (ground). There should be continuity. If there is no continuity, check that the thermostat mounting is secure.

7 Remove the sender (see Steps 9 and 10 below). Fill a small heatproof container with coolant and place it on a stove. Connect the positive (+ve) probe of an ohmmeter to the terminal on the sender and the negative (-ve) probe to the sender body (see illustration 4.13).Using some wire or other support, suspend the sender in the coolant so that just the sensing portion and the threads are submerged. Also place a thermometer capable of reading temperatures up to 120°C in the coolant so that its bulb is close to the sender. Note:None of the components should be allowed to directly touch the container.

8 Heat the coolant to approximately 40° C and keep the temperature constant for 3 minutes before continuing the test. Then increase the heat gradually, stirring the coolant gently.

Warning: This must be done very carefully to avoid the risk of personal injury.

As the temperature of the coolant rises, the resistance of the sender should fall. Check that the correct resistance is obtained at the temperatures specified at the beginning of this Chapter. If the meter readings obtained are widely different, or they are obtained at different temperatures, then the sender is faulty and must be renewed.

Replacement

Warning: The engine must be completely cool before carrying out this procedure.

9 Partially drain the cooling system sufficient
to remove the sender without spilling coolant
over the engine and cycle parts (see Chap­
ter 1).

10 Disconnect the sender wiring connector. Unscrew the sender and remove it from the thermostat housing.

11Apply a suitable sealant to the sender threads, then install it into the thermostat housing and tighten it to the torque setting specified at the beginning of this Chapter. Connect the sender wiring.

12 Refill the cooling system (see Chapter 1).

13Install the fuel tank (see Chapter 4).

6 Thermostat and thermostat
housing - removal, check and ||
installation ^

Removal

Warning: The engine must be completely cool before carrying out this procedure.

1 The thermostat is automatic in operation and should give many years service without requiring attention. In the event of a failure, the valve will probably jam open, in which case the engine will take much longer than normal to warm up. Conversely, if the valve jams shut, the coolant will be unable to circulate and the engine will overheat. Neither condition is acceptable, and the fault must be investigated promptly.

2 The thermostat is located in the thermostat housing, which is mounted to the frame under the fuel tank.

3 Partially drain the cooling system sufficient to remove the thermostat and thermostat housing without spilling coolant over the engine and cycle parts (see Chapter 1).

4 Release the clip securing the overflow hose to the radiator filler neck and disconnect the hose, then unscrew the mounting nut for the thermostat housing bracket, noting how the bracket fits (see illustrations).Release the bracket from the rubber shroud.

Cooling system 3»5

6.4b... and unscrew the housing bracket nut

Date: 2016-01-14; view: 635