So I complete this mass air conversion and the air boxes are different in that the SD has a breather filter in the box.

Hose goes to oil fill tube. MA doesn't have it.

So I improvised.



My chapter bud gave me a bit of grief about the optics of my bodged filter.

So I made an impulse buy at the Autozone:



Yah, know, the red was a buck more . None the less, it completes it nicely.

 

I like your valve covers.

 

I wish we had some cool valve covers for the 7.3... I just need to paint mine Ford Blue and call it a day.

 

Thanks, I don't do a lot of bling, but I wanted a pair before the go extinct.

I've painted a lot of stuff over the years cause they just don't make it, or I just couldn't afford it if they did.

 

I hear that. Necessity is the mother of invention, after all.

I've seen a couple of T444E motors on ebay that are all blue, and they sure do look nice.

 

Laser scanner, the right CAD program, bar of aluminum & CC 3 axis mill...

Oh & money.

I'd love to do it manually, but hey...

 

I have everything minus the scanner and the mill.

Hope to have it someday, but money is required for all that.

 

Isn't that an unmetered air leak? Intake pulls vacuum on crankcase through pcv, and that filter is now venting the crankcase to atmosphere. Ford routes the crankcase vent into the intake plumbing downstream of the MAF meter to make it a "controlled" air leak (or at least accounted for). I know my truck changes idle when I pull the oil fill cap, and there's some vacuum there. Venting that to atmosphere doesn't seem right..

 

It goes to the Y in the tract after the meter I believe, but I don't have one to look at.

But so far it runs & idles fine & the PCV has a good draw.

 

Glad it's working well for you. But in case it ever gives you some grief that you're not able to tune out, GoinBoarding is correct. The MAF engines are supposed to have that PCV air accounted for.
On car and Explorer/Mountaineer 5.0 engines where the oil fill is on the passenger side, it's typically a hose fitted between the oil filler neck and the throttle-body itself. Just ahead of the blades (so it's not full manifold vacuum) with a 90° 3/8" hose fitting.
Is your PCV valve in the other valve cover, or in the back of the manifold?

Paul

 

Yes, it's in the VC & functioning as well as before.

I have not checked the vacuum since the conversion, but will throw a gauge on it.

I'll see if it's higher/lower than the #17-18 it had after the rebuild.

 

Thinking about this more. When an unmetered air leak would be most problematic, wot, vacuum is lowest, so this likely won't make a difference (I think). Maybe just something to note, and keep in mind if any issues arise later.

 

Hey, I'm all for keeping tabs on stuff that might bite where it hurts.

Vac tests out at idle 17-18 Hg, most steady at 17.25

No WOT test.

One day I might get an actual gauge, the mityvac looks silly wire-tied to a wiper.

It's no sweat to run a hose 5 liter style from Y nipple to oil fill & see how it acts.

I just wonder if there are back flow & no draw periods in different throttle positions.

 

That setup is no different than the factory routed to the air filter....the pcv draw is always on the intake manifold side of the throttle body, and mass airflow sensor and, therefore, always unmetered air. It's designed to be small enough not to cause a problem, and is why the valve is variable in its opening based on vacuum.

 

I don't believe that is correct '89F2. At least not for a MAF engine.
I'm no expert though, so will hold short of saying neener neener and I told 'ya so! But I think you're still off by one.

On the SD's and carbureted engines, the return-air is taken from wherever because it's not metered. So for that type, you are correct.
On any MAF setup though, the return-air is (always?) behind the MAF.

You're correct that the valve itself is always on the intake side, because that's where it gets it's full vacuum and where it will suck the junk out of the crankcase and back into the intake to be burned the most efficiently. Naturally.
But the "clean air intake" on a MAF engine is always behind the MAF so it is always metered. The total air in the system is measured as it passes through the MAF and then becomes part of the controlled intake process no matter whether it goes straight into the combustion chamber, or straight into the crankcase first, then into the combustion chamber.
By it's very location then, the filtered air return becomes fully metered air too.

In Scndsin's case then, the original setup which had a simple filter inside the air cleaner housing, it's perfectly fine to replace it with a little cone filter on the intake. Just like on a carbureted engine.
But now that it's been changed over to a MAF setup, it theoretically needs to have the filtered air return for the PCV plumbed into the intake tract somewhere behind the MAF, and in front of the TB. Becoming a semi-closed loop.

Ok, as I said I'm not a total expert on the subject. And maybe there are engines out there that have a different setup. But I've never seen one. Every one I work on that is a MAF type will have the fitting, usually, either on the plastic tubing between the engine/TB and the filter/MAF, OR the oil fill tube in the case of many Ford Windsor family V8's.
I've hardly even opened the hood on 4.9's, so can't say theirs are. But I bet they're the same if they're also Mass Air Flow engines.

Happy to hear otherwise though. I'd rather be right all the time of course(!) but still like to learn new stuff. So be glad to hear of other setups that I don't know about.

Paul