Catch cans

[yamahaSHO]

Some of you make this seem like something difficult. My diesel truck doesn't suck back into the intake (and would be pointless since vacuum isn't something you really see in a diesel). Either VTA or use an AOS in a closed system.

If you are special enough to "alter your crankcase pressure" to the point of failure, you're looking at blowing out some seals and pushing oil through the 'seals' of your turbo to be burnt in the exhaust... Not something I'd call a failure, just something that would need address, properly. Venting through a filter doesn't keep the pressure the same. It prevents the induction system from ever pulling a vacuum on the crankcase.

 

[SHOdded]

Is the "Home Depot" type setup for the Gen I/II (implemented as clean side separator in this case) a suitable alternative for forced induction engines also, Jason? Would it alter crankcase pressures significantly?

 

[yamahaSHO]

The key is not to route boost back into the crankcase. I use an AOS on my current turbo car. I used a bottle as a catch can on my boosted SHO.

If you're keeping the stock routing, but just adding a closed loop AOS or catch can, you'll be like stock, but with a can in between. I personally only use AOS' anymore.

 

[SilverSH0]

Venting through a filter doesn't keep the pressure the same. It prevents the induction system from ever pulling a vacuum on the crankcase.

Please explain to me how it's going to be any different from the stock setup? In the stock setup the hose is connected to the intake air tube right behind the air filter. So by disconnecting the clean side hose and putting on my own filter, how does that change anything?

 

[rubydist]

The stock system can pull a small vacuum on the crankcase because it is connected to the intake (that is why it is called a "positive crankcase ventilation system"). venting to atmosphere prevents that from happening.

 

[SHOdded]

The net outcome is that maintaining a closed system, with or without a catch can, is of vital importance, since that is how Ford designed it. If you add something to the path, it should be as free-flowing as possible.

 

[SilverSH0]

The stock system can pull a small vacuum on the crankcase because it is connected to the intake (that is why it is called a "positive crankcase ventilation system"). venting to atmosphere prevents that from happening.

I think you're misunderstanding me. I'm not talking about touching the hoses connected to the intake manifold (dirty side of the system). That will stay as it should and untouched. Make sure you understand in the PCV system there is s clean side and dirty side. The clean side normally is a clean air intake when the manifold is under vacuum. The problem is that under boost the intake becomes and exit for oil laden vapors. What I'm venting is only a vent under boost. It's the clean air intake under normal operation.

 

[yamahaSHO]

Please explain to me how it's going to be any different from the stock setup? In the stock setup the hose is connected to the intake air tube right behind the air filter. So by disconnecting the clean side hose and putting on my own filter, how does that change anything?

It sounds like you're really wanting an AOS. When people use cans with filters, they open up to atmospheric.

 

[SilverSH0]

It sounds like you're really wanting an AOS. When people use cans with filters, they open up to atmospheric.

Exactly what I want for the clean side of the system because I don't want it feeding oil into my CAC under boost operation (such as cruising down the interstate at 75 mph on a trip).

It seems to me a catch can is an air/oil separator. According to LMS a catch can has the potential to change the pressure on the intake. I can see that as a potential as the catch can might act as a restriction. If a catch can would be a restriction, I would have to imagine that would hold true for various AOS. However, a filter on the end of the clean side hose would act no different than the main air intake filter of the car.

 

[yamahaSHO]

A catch can and AOS are not the same as the catch can is not designed separate the oil/moisture in a closed system. Changing the pressure on the intake? Do you mean crankcase?

I don't have a diagram of the Ecoboost PCV setup, but if the "clean side" is the fresh air intake, I've always removed those in favor of putting both lines into an AOS being drawn from the turbo inlet, which is generally an accepted method across the board (Crawford runs their AOS' this way, which I have on two different cars). The other option would be putting a check valve or solenoid on that line directing air through the AOS at WOT/high load and around it when cruising under vacuum.

 

[Metroplex]

Now the GM wrenches will have a similar canary with GM's all-new LTG turbo motor. The first few that fail out in the real world will have a mythical issue that is inexplicable, therefore will need an overthought solution.

I wanted to point out that GM has had a GTDI engine since at least 2006: the LNF. GTDI 2.0 that makes 260 hp stock, easily tuned to make 310-330 hp. The PCV system uses 3 connections at the valve cover. The engine was first used in the Opel GT (Saturn Sky Redline) then quickly made its way over the Pontiac Solstice GXP, eventually Cobalt SS Turbo and HHR SS. The Fisker Karma also used this engine in its first iteration. But I understand your point being that it wasn't a common engine.

Here are the 3 connections for the LNF: A fresh air inlet breather with a check valve attached to the air intake hose. A direct connection to the turbo inlet (like piped right into the turbo), and a PCV valve located under the intake manifold.

Would adding an open breather for the fresh air intake on the SHO/EcoBoost be OK?

 

[2012korn]

For the record. The jlt catch can goes on the dirty side. Like every other catch can. Ones with a clean side separator like the upr are more extensive. And no. It won't void your warranty. And no, you aren't going to change pressure in the crank case. Despite what lms is trying to feed you people.

 

[Majestic]

FWIW, the catch can was a crutch we used back in the 80s to remedy a weak/defective PCV valve on the 84-86 SVO. The easier and better fix was always to get a proper PCV valve from Motorcraft.

 

[6500rpm]

I'm trying to get up to speed on the catch cans as I'm taking a serious look at the system sold by McNally. It was never really a thought until I bought this car and started taking a closer look at the Fords in the fleet and the amount of oil residue feeding back into the induction system while doing tear downs for various repairs. Some of the youtube video's were showing 4-6oz of oil being captured by the stand alone units between oil changes which I'd definitely like to prevent from being pulled through the induction system if possible on my daily driver (call it an ounce of prevention). I'm having a hard time following this thread as there seems to be two completely different views on the system. What's even a bit more confusing to me is in my world of OEM vehicle repair on new vehicles, any venting of crankcase pressure to atmosphere (ie: loose oil caps, dip sticks not seated, etc) almost certainly leads to p0171 dtc setting. Ford uses variations on oil separator systems on the 2.0l GTDI, 3.5l Ti-VCT, and 3.5 GTDI so why would a stand off system like McNally's be a bad thing?

 

[Kphoenix07]

This was a fun read. Lol.
To each their own is the lesson of the day. Lol

 

[javon7065]

For the record. The jlt catch can goes on the dirty side. Like every other catch can. Ones with a clean side separator like the upr are more extensive. And no. It won't void your warranty. And no, you aren't going to change pressure in the crank case. Despite what lms is trying to feed you people.

Just curious how you know that it will not avoid the warranty? I discovered recently that someone had installed the jlt catch can on my SHO when I pulled the engine cover off. I recently bought the ESP warranty for my 2015 SHO.