chep stuff Ford filters and Ford oil ( or what ever my Ford dealer buy's in bulk ) Free oil changes were a small perk I paid for, every 5000 KM The old 04 is due for a fixing here pretty quick..

 

Motorcraft FL-820s and Mobil 5w-30 syn. I would not use a Fram oil filter for anything.

 

I'm not familiar with where the crankcase takes in air. Please enlighten me.

 

i use Castrol Gtx 10W30 and Fram sure guard oil filter

 

Mobil 1 (5w-20) and I will upgrade to a mobil 1 filter next time. (I didn't know about performance filters when I changed my oil...oops)

 

PCV ring a bell?
Positive Crankcase Ventilation.

 

Motorcraft 5W20 and motorcraft filter. Change it on or before 3,000 miles but that is only about once a year for me.

I am kind of concerned about unburned fuel contamination. Is there much of a problem with that in these engines or does EFI (electronic fuel injection) take care of that??? Specifically i am talking about driving the truck less then a mile and shutting off the engine- sometimes just across the farm yard for loading or unloading things- so the engine doesn't really get warm at all. I should probably be changing it more often but seems like a waste of money- the few miles that i put on.

 

The PCV system doesn't allow "fresh air" into the engine crankcase!! It provides an assisted escape for the blow-by from the combustion process. It is further enhanced by the fact that it operates in a vacuum. Hince the name "positive". That doesn't mean that it pressurizes the crankcase. Rather, it means that there is a positive force that draws the blow-by gasses out of the crank case. The crank case is exposed to a slight vacuum, which is used to draw out water vapor, unburned fuels, and other pollutants, and return them to the intake airstream. The engine subsequently re-burns them and passes them through the catalyst system.

 

I was just reading about this in my Haynes manual before reading trough these posts. The PCV does circulate fresh air from the air cleaner through the crankcase where it mixes with the blow-by gases. Then it is rerouted through the PCV valve to the intake.

 

Yeah? Didn't know it did that. I was thinking about the pcv valve and not the whole system.

Where does it draw air from?

 

I had the crankcase PCV breather filter become plugged on my '93 5.0 T-Bird.

The symptom was oil running down the air intake and fouling up the MAF sensor. It also ran rough at times under normal accelleration (due to the MAF being oily).

 

Of course it doesn't pressurize the crankcase, no one said that it did. In some systems fresh air is indeed able to get into the crankcase but that is not the point.
The PCV valve is just a check valve that uses the vacuum from the intake to remove excess pressure from the crankcase. The positive pressure in the crankcase is removed by the vacuum of the intake. The positive pressure in the crankcase is created by combustion by-products blown past the rings. The intake charge is ignited by the spark and some of the gases and debris may make it past your rings. Hopefully not a lot or your engine is probably in need of repair. The point is that anything that makes it past your air filter can potentially end up in your oil "hence" the need for an oil filter.This is the point we are trying to make here. The oil filter does more than filter wear metals or "filings" as you say.

 

Thanks Norm.

 

I'm with big daddy on this one except I change my oil every 3,000 miles. What part of LA. you from anyway, Big D?

 

The PCV system is used to remove blow-by gasses from the crankcase, and send them back through the combustion chambers to be burned again. Pressure in the crankcase has nothing to do with how it works, however. A hose runs from the crankcase (usually a valve cover) to a manifold vacuum source, with a check valve (PCV valve) along the way to both restrict the flow and to prevent a backfire in the intake from reaching the crankcase. Again, just to emphasize, the rate of flow out of the engine is whatever the manifold vacuum is able to pull past the restriction in the PCV valve, regardless of how much blow-by there is.

Now then, in order for the system to be able to suck the dirty air out of the crankcase, fresh air has to enter the crankcase to replace it, otherwise it wouldn't work. The fresh air enters the engine, usually via a hose that goes from the air cleaner/air filter box to the other valve cover (on V8's), or to another point in the same valve cover (for inline engines). Newer systems place the fresh air hose after the air filter in the filter housing, which filters the fresh air before it enters the crankcase, but older systems (carburetted) had the fresh air hose attached to the outter edge of the air cleaner, which meant the air didn't pass through the air filter first. Those types would attach a small cloth-like fiber filter to the inside of the air cleaner where the hose was attached, in order to filter the fresh air entering the crankcase. The fresh air entering the crankcase is only as clean as the filter it passes through. If someone was to leave out the air filter entirely, as you suggested, dirt and other foreign objects, as large as 1/8" in diameter (depending on the PCV valve), could and would get sucked directly into the crankcase.