Crankcase pressure is caused in part by the flow of air pumped past the pistons. Crankcase pressure should be low, and can be increased by worn piston rings, for example. But most of the crankcase pressure is created by rotating parts such as the crankshaft and connecting rods, which must be removed by crankcase ventilation.
If this is not done, the pressure will be dissipated by the weaker parts such as the seals. In order to ensure that there is no oil leakage where the crankcase is ventilated, a construction has been made for this purpose which guarantees that the pressure is removed but that the engine oil remains in the crankcase.
In the case of waterboxer engines (WBX), this is the crankcase breather tower, which is fitted with a loose sleeve with different outlets on the inside, which is positioned in the right direction so that only the pressure is released.
With the CT/CZ motors, the operation is the same but designed in a much simpler way without additional internal parts, it is a hollow space where we have chosen to place a deflector at the bottom that we know from the Type 1 and Type 3 motors. This stops oil splashing, so that only the crankcase pressure is vented.
This crankcase breather tower is made of plastic on the WBX and CT/CZ engines. After many hot and cold miles, the plastic eventually hardens, making it easy to tear. The weakest area is the hose connection, once broken, the entire crankcase breather tower will need to be replaced. Supplied with a sealing ring.
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