Thermostat Control - PIAGGIO 500 cc Service Manual

- Loosen the drain situated on the joint exiting from the
head;
- Keep it open until the air discharge has stopped
completely;
- Retighten the drain screw;
- Start the engine for a few seconds;
- Repeat the drain operation at the head exit;
- Repeat these operations several times until only fluid
is discharged;
- Reset the level in the expansion tank and screw on
the plug;
- Start the engine and allow it to warm up until the
electroventilation temperature is reached;
- Stop the engine;
- Reset the level with a cold engine.
Warning
- The electroventilation is controlled
through the temperature measured at the head.
Activation of the fan cannot be considered an indication
of completed discharge.
The discharge can be considered complete when a
temperature increase is noted in the expansion tank.

Thermostat control

Before dismantling it is advisable to carry out certain
checks:
- Connect the diagnosis tester and select the "PARAM-
ETERS" function(see Chapter 4-FUEL INJECTION);
- Start the engine from cold and allow it to warm.
Specific tool:
Fuel injection diagnosis tester: 020460Y
- Check manually the moment in which heating com-
mences in the left box of the radiator;
- Check the temperature indicated on the diagnosis
tester.
Initial thermostat opening: ~ 75° C
N.B.: The temperature measured by the tester is that of
the head outlet, whilst the true thermostat temperature
is referred to the pump inlet.
Cooling
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