Breather Filters? Crankcase Breathers?

SpooledupRacing

Banned
Samurai_Blue said:
During normal operation, a small amount of unburned fuel and exhaust gases escape around the piston rings and enter the crankcase, referred to as "blow-by". [6] If these gases remained in the crankcase and condensed, the oil would become more diluted over time, decreasing its ability to lubricate. Condensed water would also cause parts of the engine to rust. [7] To counter this, a crankcase ventilation system exists to draw fresh air in from the air filter and expel the gases out the PCV valve into the intake manifold. In a non-turbo engine, the intake manifold is at a lower pressure than the crankcase, providing the suction to keep the ventilation system going. A turbo engine usually has a check valve somewhere in the tubing to avoid pressurizing the crankcase when the turbo produces boost.

If an engine is damaged or enters old age, gaps can form between the cylinder walls and pistons, resulting in larger amounts of blow-by than the crankcase ventilation system can handle. The gaps cause power loss, and ultimately mean that the engine needs to be rebuilt or replaced. [6] Symptoms of excessive blow-by include oil being pushed up into the air filter, out the dipstick[8], or out the PCV valve.

purpose of the valve cover filter....imo i think leaving the pvc tube is better than the filter
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You over looked one important thing....

The PCV system is a totally different system then the breather system..

When u pull the breather hose and replace it with a breather filter you still have your PCV valve... that paragraph is written about the PCV valve and its system/function..

The PCV valve is either in the top of the valve cover OR in the lower section of the intake manifold.. its hose runs into the intake manifold (not into the air filter piping)

PCV or Positive Crankcase Ventilation is what is used to remove the unburned gases that pass by the rings in the engine.. This system works hand in hand with the EGR valve

EGR or Exhaust Gas Recirculation valve burns up the air which gets pushed back thought the PCV into the intake.

The breather hose that u see that goes into the air filter piping that is exactly what u think it is it is a FRESH AIR HOSE. it is put in the air intake hose to receive filtered fresh air from the outside of the engine Its other function is to be a vent to make sure the engine does not pressurize

If you were to remove that hose and "cap" it off you would pressurize the crank case and there for blow the piston rings to shreds..

The only problem with a vent filter is that when u have an older car that has excessive blow by that filter will trap some oil and over time leak and spray oil in the engine bay HOWEVER if your having this problem just think what it is doing to your air filter and throttle body..

Breather filters are just fine to use. Unless you are a greenie.. then I would not recommend owning a car at all.. :)
 

dc2GS-R

Super Moderator
Samurai_Blue said:
A turbo engine usually has a check valve somewhere in the tubing to avoid pressurizing the crankcase when the turbo produces boost.
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The PCV valve acts as a check valve. They only flow one direction

Ballerin1 said:
But I don't see why it would be bad, what's the worst that could happen?
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It's not that it's "bad", it's just there is no benefit to it. It will reduce the efficiency of your crankcase ventilation but not to a point where it really makes a difference either way. It's basically a mod that people do because they are just too lazy/cheap to do it properly and get a catchcan. The catchcan still allows for the vacuum without having oil spit in your intake.

The issues with it are just magnified by turbo cars. PCV valve closed under boost as not to pressurize the crankcase so that hose is the only ventilation you have. Removing it drastically hampers that considering you now have a turbo sucking air out of that area creating a good amount of vacuum. Leaving it gunks your intercooler, throttle body...etc with oil residue. Installing a catchcan gives you the proper crankcase ventilation, even under boost, without putting oil through your intake tract.
 


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SpooledupRacing

Banned
Cheesenip said:
that breather will fill with oil over time anyways, I dont see why people just dont get a catch can.
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this is true slowly even on a good engine it will get oil soaked.. so unless u buy a K&N breather that u can wash out it really has no use but looks. you get no gains from using it over plumbing into the intake or using a catch can.

Honestly I like the look but I think a catch can look MUCH better
 

SpooledupRacing

Banned
Cheesenip said:
over time a k&n will fall apart from the oil.
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honestly I ran a K&N breather on my old Conquest for over 50K and NEVER had any issues with blow by into the breather more then I could handle by a wash.

Hell the car didn't push any oil into the filter until I was in the 25psi range on a car with low compression anyways.
 

Samurai_Blue

Yolo Whippin'
understood about the pvc valve i probably got that mixed up with the tube. Cause the filter goes on the little thing from t he engine and t he tube delivers the air
 
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