Pic. 39. Air filter:
1 - warm air intake hose; 2 - cold air intake; 3 - thermostat; 4 - filter element; 5 - cover; 6 - filter mounting plate; 7 - remote bushing; 8 - gasket; 9 - branch pipe for removal of crankcase gases into the throttle space; 10 - exhaust manifold of crankcase gases; 11 - air filter housing; 12 - warm air intake; 13 - thermostatic shutter; 14 - thermostat housing.
The thermostat consists of a plastic housing with a damper 13, the position of which can be changed by moving the handle manually. Depending on the ambient temperature, the handle can be placed in one of three positions: HOT - for taking warm air through the air intake 12; COLD - for cold air intake through intake 2; intermediate position, when the damper is in the middle position and air is sucked in through both intakes.
The vehicles under consideration can be equipped with thermostats with an automatic damper drive from a thermal force element installed in the thermostat housing and providing automatic opening and closing of the thermostat damper, maintaining the air temperature at the inlet to the air filter 32-42°C. On top of this thermostat there is an additional damper pneumatic actuator connected by a hose to the cavity of the inlet pipeline. When idling, due to the increased vacuum in the intake manifold, the damper will be in the open position, which ensures that warm air enters the engine to achieve a more complete combustion of the working mixture and reduce exhaust gas toxicity.
Intake pipe
The inlet pipe is cast iron, cast, mounted on the cylinder head studs through two sealing ferronite gaskets common with the exhaust manifold. Sealing gaskets and fastening nuts for disposable use.
The inlet pipe has a platform for installing a carburetor and four channels for supplying the working mixture to the engine cylinders. The pipe has a mixture heating jacket, which is connected by channels to the cylinder head cooling jacket. The liquid is drained from the inlet pipe heating jacket through a hose and tube 1 (see fig. 27) to the coolant pump 15.
Gasoline condensate formed on a cold engine is drained from the inlet pipe to the outside through a drain pipe. To eliminate noticeable lean mixture at idle, the drain tube has an outlet with a diameter of (0,8±0,1) mm.