Do I need a breather on my valve covers?
Yes, the breather is still necessary. The PCV system sucks fresh air through the breather, out the PCV valve and back into the intake.
Do I need an oil breather cap?
All modern cars will require an oil breather system of some sort. If this pressure is allowed to build up and is not vented efficiently it can result in oil leaks from around the gaskets, crank seals, dipstick tube, and any other engine oil seal as the oil is effectively blown out by the increased crankcase pressure.
What is a breather on a valve cover for?
The thought behind the breather is that you are supposed to get more fresh air flow down into the crankcase from the valve cover. This increases the cycle of oil vapor flow out of the crankcase. The added fresh air displaces the oil vapors in the crankcase with the assistance from the IM vacuum sucking it out.
Is a crankcase breather necessary?
The crankcase ventilation system works to relieve any pressure from the engine’s crankcase attributed to blow by gases by rerouting the gases back into the engine’s intake manifold to be consumed by the engine. This is necessary, as excessive crankcase pressures can cause oil leaks to form if allowed to build too high.
How does an oil breather cap work?
When the vehicle is moving, airflow across the open end of the tube creates suction (a “draught” or draft) that pulls gases out of the crankcase. To prevent a vacuum being created, the blow-by gases are replaced by fresh air using a device called a breather. The breather is often located in the oil cap.
Why is oil coming out of my breather?
If the engine is producing blow-by gases faster than the PCV system can dispose of them, an increasing surplus becomes trapped in the crankcase, causing excess pressure and, inevitably, oil leaks. In addition, the low-level vacuum draws in fresh air to the crankcase from the crankcase breather.
Do I need to drain oil before removing valve cover?
No, you don’t have to drain the oil to change the valve cover gaskets.