old school Woody, you're an engine builder right ? todays engines are running much closer piston-to-cylinder wall clearances....we can lose it on our 5.4

intake vacuum helping the ring seal the gap between the piston and cylinder wall to help prevent combustion gases from blowing by into the crankcase is just not something I see as a consideration on our modern close tolerance 5.4 ....thats the rings job and their getting no slight vacuum help.
besides as RPM increases above idle its blowby CFM's that take over up to 6000 rpm with piston velocity approaching 65MPH with 1100 G's exerted on the rotating mass.......

 

I called them about it and they could not say that their product would stop all the oil. They tried to talk around it for about 10 minutes with me but I stopped them and said this is a yes or no anwser will it stop the oil. They responded with not all of it.

 

No I'm no engine builder but I do know a few things. Mostly I have learned alot from hanging around Arthur for about 3 years.

 

just out of curiousity, why is the pcv hose going down to the lower intake underneath the intercooler even there in the first place? can we just plug it and leave the rest? that would atleast cure the puddling. plus you would still atleast get vacuum to the rings.

I know that some of the 4.6 mod motor guys run vacuum pumps on their crankcases. if the motor didnt need them and they didnt help then why would they use them? just curious

 

oops, pressed enter twice on accident.

 

When the vacuum is high at idle or off throttle, the oil mist is sucked up and fed through the plenum, past the supercharger and into the intercooler. Once there is boost, the oil that accumulates in the valley is pushed back and either falls back into the valve cover through the non functioning pcv valve or back up to the plenum and the cycle starts all over again. If you blocked that line at the bottom of the valley, the oil would still be sucked up through the plenum but would have no where to go. Oil would puddle at the bottom of the intake and get burned eventually as it is fed into the cylinders.

Ford already knew this problem and this was their way around it. This is possibly why they say that a quart of oil being consumed per 800 miles is acceptable.

The reason the pcv system is there even though it's no longer needed is to keep the crankcase gases from entering our atmosphere. Yup, it's to keep the EPA happy.

 

Cpeapea: Vacuum pumps and "vacuupan" systems reduce the amount of air and/or gases in the engine. As the pistons move up and down, the air in the block has to follow. If the piston is moving at 5000 rpm as it is coming down, the air has to move out of the way at the same speed. Happily, for each piston that is moving down, there is another one that is moving up, but the air still has to move around like mad - and that takes horsepower. It has been suggested that those "pumping losses" may be well over 10 hp.

As such, I'd like as much of a vacuum as I can get in my block, but I also want the intercooler to stay clean. While a solenoid valve that opens when the truck is off to drain the oil back to the pan would cure part of the problem, if we can keep the oil out of the intake, there will never be a need to drain the manifold. It is going to take either a complete re-design of the system or a pair of very efficient coalescing filters to do the job. I've ordered a pair to install in the PCV lines. That should allow the system to work as designed (for what that's worth) and keep the intercooler clean. I'll post the results once I know. If that does not work, breathers are next.............

 

The plot thickens...

 

I had a little more time to play with this today. I think I've figured out an easy fix that takes only a couple minutes and about $25.00. Since it involves disconnecting the PCV system this modification is for off road use only. Got that? Ok, AutoZone carries some small tapered element breathers at about $10.00 that pop right in the right hand valve cover. They even come in red, yellow and blue. The left cover is a little more complicated. It has a tube sticking up that is about 5/8 od. The breathers have about a 7/8 od, so I took a piece of 5/8 tubing, slipped it into some 7/8 clear vinyl tubing and it goes on the left side like a champ.

Now then: About the tube from the "drain" at the back of the manifold. That fitting is so far down the back of the engine that you simply cannot get to it. It also sees full boost, so if it is just capped and the the boost pops the tube off the drain fitting, you are going to be in serious trouble. But I noticed that it runs to the intake plenum, right behind the idle air control valve. If you simply hook it directly to that point what happens? Both that point on the plenum and the manifold drain are on the far side of the throttle blade, so there may be some air circulation from top to bottom and vice versa, but at least the boost has a place to go and won't pop the line off. We did a little experiment. Remove the right hand PCV hose assembly that goes from the valve cover to the plenum. Leave the hose that comes from the drain and tees into the center of that PCV hose assemby in place. Replace the tee with the elbow that was on the PCV valve so the drain hose now runs right to the plenum. The truck seemed to start and run normally after that change. Oh, don't forget to plug the hole in the intake elbow where the left hand PCV hose went.

This should be a 100% fix for any new oil getting to the intercooler. Any residue in the bottom of the manifold may continue to circulate, but it is going to take a lot to get it all the way to the top of the plenum.

 

Concerning the bypassing of the bottom intercooler plenum to the top, isn't that how the bypass valve works? In other words, wouldn't you loose a bit of boost? Seems like the only solution is blocking the lower plenum althgether.

As far as adding filters to both valve covers, if you block the lower plenum, and blocked where the hose went into the passanger side tee, wouldn't that be an environmentally friendy solution (since the internals don't see any boost pressure and can now operate like a normal PCV system)?

Without the vented boost, that might keep the oil from blowing out the drivers side cover into the intake elbow. Of course, the passanger-side PCV should be replaced with a one-way type, as boost no longer has to have an exit.

Just a thought...

 

The oil that is in the manifold accumulates over time. It is a result of the condesation of the oil vapor that is fed into the intake stream. When it condenses as liquid oil and coats the intercooler, the efficeiency of the intercooler is diminished. In a carbureted engine, the gasoline flow carries any oil with it and the manifold stays fairly clean. In the Lightning, the injectors are well beyond any of the aforementioned system, so the intecooler becomes an oily mess. Yes, the drain line going to the plenum does serve as a boost bypass and will reduce boost as much as the 1/4 inch inside diameter ot the fitting on the bottom of the manifold will allow. The best thing solution would be to take it out and replace it with an aircraft style (AN) elbow, a section of braided hose with a threaded plug at the end which would hang down by the trans so you could manually drain it. The problem is that you cannot get to that fitting. It is in a place where arms and tools cannot reach. So, unless you're willing to actually pull the manifold and replace the fitting with a pipe plug, we're stuck with coming up with a workable solution.

As far as replacing the passenger side PCV valve with a one way type, the drain line comes in above the PCV valve, so the boost does not get to the valve cover. All the boost does is to take the oil that has accumulated in the manifold and force it into the plenum so it gets one more trip through the intercooler. To keep the intercooler clean, you have to prevent oil from getting into the manifold. I'm still trying to come up with an "environmentally friendly way" of doing so. Coalescing oil filters in the lines are probably the best solution. All I need to know is how many CFM they need to flow.

 

If this was as big a problem as one would gather from reading these posts then oil consumption would be a factor. I've owned a '99 "L", an '00 "L", and now an '03 Cobra and have never had oil consumption problems...in fact I have never noticed a drop in levels between changes...ever. Sure, there's a little coating of oil but like the teaspoon of oil on a concrete driveway looks like a quart so does the little that's in the intake system. Is there really a problem or just a fixation?

 

I read parts of this thread.

Riddle me this.

I have an oil seperator (actually a water seperator from an air compessor) It does get oil in it.

However I have never had to change it because the oil disappears.
Now I doubt it is being sucked back throught the valve cover, I'm guessing it is going through the intake and coating the rotors and intercooler.

Can someone tell me where the oil in the seperator is going?

 

How much boost were you running on the Lightnings and now on the Cobra?

 

13-15 PSI