80
——Clip the thermostat seat, and put the rubber seal ring into the thermostat hole.
——Install the thermostat (with spring outward)
——Install spring clip, ensure that the clip is clipped in the thermostat seat groove.
——Install the sealing gasket of the new thermostat seat on the thermostat assembly with a bolt.
——Install the thermostat together with thermostat assembly into the rear end hole of cylinder head. Finger
screw in 3 bolts and tighten to 9-12Nm.
——Tighten the hex head plug with the sealing gasket on. Tightening torque is 38-42Nm.
——For the engine equipped with electrical heater, install air intake preheating switch. Tightening torque
is 38-42Nm.
3. Removal and assembly of the water temperature sensor. Removal:
——Remove the water temperature sensor (at the exhaust side, under the rear lug).
Assembly: ——Before installation, apply the lotite
sealant 243 onto the bolt threads. Finger screw in and tighten
to 7.0-10.0Nm.
【
15
】
. The intake and exhaust system of the engine
1.
Description for the intake and exhaust system of carburetor engine.
The intake system of Carburetor
Engine 480 includes: air filter, Intake hose, Guide cover, Carburetor, Intake hose, Intake air preheating
hose of Positive Crankcase Ventilatio
（
n PCV
）
, and so on. ——Air filter type is 1GD129607G, and its basic
parameters are as the following: Filtering area: 100cm2 nominal air flow(L): 600
±
150
filtering efficiency:
≥
99% filtering resistance: 2kPa
Fig.126 intake and exhaust system arrangement of carburetor engine
——The air filter is equipped with an intake air temperature controller. When the temperature is low, the
hot air intake valve controlled by the temperature controller will open and the hot air, flowing by the
exhaust manifold, will be directed into the air filter from the intake preheating hose to supply more hot air
and facilitate the fuel atomization during cold winter. As temperature is high, valve is shutted off and the
hot air is not permitted to enter the air filter. ——Carburetor (see Fuel System)
