BMW E34 crankcase breather and oil vapor
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What symptoms does a faulty breather cause in the E34?
The breather ventilates the crankcase. On the M60, a torn breather valve or oil separator diaphragm lets oil vapor into the intake manifold. Symptoms are poor idle, loss of power, high emissions, oil consumption and blue smoke. Removing the oil cap can be difficult because of the strong vacuum.
How do you prevent the M50 breather hose from freezing?
On the M50 the larger hose (no. 3) and its metal fitting can freeze blocked. Clean the hose of oil and water sludge and insulate it with foam rubber or sound insulation mat and tape.
Is the white sludge under the oil cap a sign of a fault?
Usually not. White sludge normally forms when the car is driven on short trips and the engine does not warm up properly. A blocked breather, on the other hand, can raise the crankcase pressure and push the gaskets out.
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