Suzuki Burgman 400 - Service manual > Thermostat

Thermostat Removal and Installation


1) Drain a small amount of engine coolant. Refer to "Cooling System Inspection".

2) Remove the air cleaner box. Refer to "Air Cleaner Box Removal and Installation".

3) Place a rag under the thermostat case (1).

4) Remove the thermostat case (1).

Engine Cooling System

5) Remove the thermostat (2).

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Install the thermostat in the reverse order of removal.

Pay attention to the following points:

Engine Cooling System

Thermostat Inspection

Inspect the thermostat in the following procedures:

1) Remove the thermostat. Refer to "Thermostat Removal and Installation".

2) Inspect the thermostat pellet for signs of cracking.

Engine Cooling System

3) Test the thermostat at the bench for control action.


4) Immerse the thermostat (1) in the water contained in a beaker and note that the immersed thermostat is in suspension.

5) Heat the water by placing the beaker on a stove and observe the rising temperature on a thermometer (2).

Engine Cooling System

  1. String
  2. Water

6) Read the thermometer just when opening the thermostat. If this reading, which is the temperature level at which the thermostat valve begins to open, is out of the standard value, replace the thermostat with a new one.

Thermostat valve opening temperature
Standard: Approx. 82 ºC (180 ºF)

7) Keep on heating the water to raise its temperature.

Just when the water temperature reaches specified value, the thermostat valve should have lifted by at least 3 mm (0.12 in). A thermostat failing to satisfy either of the two requirements (start-to-open temperature and valve lift) must be replaced.

Thermostat valve lift "a"
Standard: 3 mm and over at 95 ºC (0.12 in and over at 203 ºF)

Engine Cooling System

8) Install the thermostat. Refer to "Thermostat Removal and Installation".

See also:

 Suzuki Burgman 400 - Service manual > Cooling Fan

Cooling Fan Inspection Inspect the cooling fan in the following procedures: 1) Remove the left footboard. Refer to "Footboard Removal and Installation".

 Suzuki Burgman 400 - Service manual > Water Pump

Water Pump Components Water pump cover O-ring Impeller Mechanical seal Oil seal Mechanical seal ring

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