The system of ventilation of a case — closed, compulsory, acting due to depression in an inlet pipe and the air filter.

During the operation of the engine gases from a case are sucked away: idling and small loadings — through the calibrated carburetor opening in an inlet pipe, on full loadings — via the air filter, on other modes — via the air filter and the calibrated carburetor opening.

On the working engine at serviceable system of ventilation in its case there has to be a depression which can be defined by means of the water piezometer attached to a branch pipe of the index of level of oil. If the system works abnormally, then in a case there will be excessive pressure. It is possible in case of coking up of channels of ventilation or excessive break of gases in an engine case.

At operation of the car do not break tightness of system of ventilation of a case of the engine and do not allow its work at an open maslozalivny mouth: it causes the increased wear of the engine.