BMW «528», «525», «520»
A heating damper is installed in the intake pipe of the intake silencer, controlled by a thermostatic element due to thermal expansion.
Every 15,000 km of run, check the ease of movement of the damper and, if necessary, lubricate the swivel joints with oil.
When the damper is closed, the carburetor is fed with air heated by the heat of the exhaust manifold. At an ambient temperature of about 25*C, the damper opens and closes the heated air supply channel.
BMW «518»
To the right of the radiator, in a special case, there is an automatic air heating valve controlled by a lever, which is installed outside the case and which is set in one of the following two positions:
- position «W» («Winter»): air entering through the front of the vehicle is mixed with warm air heated (up to about +30°С) due to the heat of the exhaust manifold in a ratio depending on the ambient temperature and engine temperature. At an ambient temperature of about +30°C, the heated air supply channel is completely blocked, and the unheated air channel opens.
- during the warm season (at temperatures above +10°С) set the outer valve lever to the position «S» («Summer»).
The valve body cover is secured with a screw.
Every 15,000 km of run, check the ease of movement of the valve in the position «W» lever and, if necessary, lubricate the swivel joints.