OC 234 Knecht/Mahle oil filter

Purpose of the oil filter:
The oil filter is designed to remove harmful particles from the engine oil resulting from the wear of friction surfaces, as well as due to the ingress of solid products of fuel combustion into the oil.
 
Oil filter structure:
The oil filter consists of a metal housing, a filter element and two valves: bypass (sometimes called safety or bypass) and check (anti-drain) valves.
 
Oil filter working principle:
After starting the engine, the oil pump is started, which circulates pressurized oil from the oil pan to the engine. Before entering the engine, the oil passes through the oil filter element, while being cleaned of harmful impurities. When the filter element is dirty or when the engine speed is sharply increased, the bypass valve is activated, which ensures the supply of oil to the engine. The non-return valve keeps the oil in the filter when the engine is not running in order to ensure that the set pressure in the system is quickly established during engine start.