I collect about a 1/2 oz of this foul smelling crap per tankful (4.6L).



From oil that only had 1500 miles on it:



Its not about short term cost. Its about applying sound mechanical knowledge over the life of the engine - from new onward. It not only helps reduce carbon in the intake, valve stems, combustion chamber; its also about keep the proper A/F ratio and avoiding detonation - remember the new pistons aren't forged metal like the old days.

And yes it's a bit of a pain for some knowing they can't go two full tankfuls without draining (depending on the size of your sep). But I'm lifting the hood anyway checking the oil, cleaning the engine bay after washing, etc.

To each their own, but I have a mechanic's mind and intend on caring for my machine properly. Thinking that way has helped my F150 reach 253k and still pullin'! It also kept my Jensen-Healey/Lotus running 15 years after Jensen went out of business and I finally sold it running strong.

Here's one commentary (of many available). Keep in mind Steeda is in a unique partnership in Ford's technology transfer program on some of their items. Surely they wouldn't recommend and sell oil seps if they were detrimental to the engine.

 

For the original post, I'm not sure what your unsure about. If ford or any other company were to put everything possible to make an engine last forever, they would cost a fortune and they would sell less cars. Don't over confuse the matter. I put one on my car and was AMAZED......AMAZED at how much oil was deposited in there. Who cares why ford didn't put one in there, concentrate on the fact that oil is flowing back into the intake, period. Every one of the five stangs I have had that hasn't had a catch can when u rip apart the intake for mods, etc you wouldn't believe how black and gunked up they are. If the price is your concern, that's understandable, but to question it's need is ridiculous. I had at least a teaspoon in mine in like 400 miles. Get it...please lol.

 

N btw for those who are saying they have never heard of a catch can before this forum, that is basically telling me you are not in touch with modern high performance modded cars. Christ if you have ever ripped an engine apart we wouldn't be having this conversation. Will not having a catch can destroy ur new stock five liter, no, but will it make ur car run cleaner, absolutely. While we are on this matter, if fords engineers were truly into giving us the best longest lasting product, why do they come with $hit tires, inadequate suspension, and let's not get started on all the tranny questions out there. Come on man........

 

Ford or any automaker would never install one of these from the factory. People complain about 5k oil changes. Imagine if they had to empty a catch can from time to time. Thats why the car is designed to burn it off or recirculate. Doesn't mean a catchcan is not helping because it is, I have had one on my car since it was new and I'm glad i chose that route. Trust me your not hurting the car in any way by installing one

 

Just a small tidbit - most engines out of Mercedes come with a catch can these days, and if not an actual can, some of them have a catch/valve inside the valve cover itself.

Back in the day, this stuff was just vented to the atmosphere, or a tube pointing down to the road. Same thing with purged fuel vapors. This is a big EPA no-no nowadays, and the most common thing for manufacturer's to do (and the easiest) is to pump it into the intake.

Some companies have attempted to catch the excess and dump it right back into the oil pan, unfortunately this isn't ideal as gas particles merge with the oil, then you end up with gas in your oil, etc etc.

There is no perfect answer - the catch can is just one of the better ideas, as it's no more maintenance than having to fill your gas tank with fuel. No long term harm done gunking up your intake/valves by pumping it into the intake; no gas in your oil pan from trying to redeposit the oil there; all you have to do is empty a little metal container every now and then.

Ford's engineers wanted to do forged rods when they built the Coyote, but couldn't due to cost restrictions. Does that mean forged rods aren't better, just because the car doesn't have them stock?

 

Exactly - it was never piped into the intake to be recycled (therefore caked & baked) in the combustion chamber. Carbon was/is the death of engines.

Yeppers. But there's a lot of non-mechanic Mustang owners these days.

 

Here is a little science behind why these oil separators have benefits on our gas engine cars...

Diesel engines, because of their necessary very high compression ratios generate significant amounts of blow by and as a result, crankcases must be ventilated. In addition, the heat generated from the engine combustion, blow by and bearings causes the oil to smoke. (actually the oil forms a sub-micron mist that condenses and looks like oil smoke). Because of emission and air pollution issues, these oil mists can't be vented to atmosphere any longer. However, original designs of CCV (closed crankcase ventilation) Systems caused other problems. See these 2 attachments that show their fleet and stationary diesel aftermarket and OEM suppliers approach to oil mist.

http://www.zemarc.com/Content_pages/...ex20040317.pdf

http://www.donaldson.com/en/engine/s...ary/053490.pdf

 

Yup. You'd see it.

 

[quote=HPwhitevert;6062382smoke. (actually the oil forms a sub-micron mist that condenses and looks like oil smoke). Because of emission and air pollution issues, these oil mists can't be vented to atmosphere any longer. However, original designs of CCV (closed crankcase ventilation) Systems caused other problems. See these 2 attachments that show their fleet and stationary diesel aftermarket and OEM suppliers approach to oil mist.

That's why I use Amsoil. It don't build up a mist in your engine and I think that's why I never had oil in the plenum of my 07 GT.

 

Thanks for the input. There are some good points in this thread and also some flawed logic and fairly specious arguments in favor of the catch can.

My original question was why AREN'T you running one? Is there anyone else who can share their opinion?

My gut feeling is that the catch can is useful and may reduce deteroration of the engine in the long run but unlike some in this thread, I'm not willing to label who disagree as ignorant...and I also know that a gut feeling is not always the best guide for our actions.

Some of you guys may claim to have a "mechanic's mind" but I would rather hear from engineers on this one.

So years back, I had to pull the intake manifold on my Miata and sure enough, it was coated with oil residue....and the sight of it disturbed me...but the car already had 120k miles on it and I didn't have time to do a complete engine tear down to clean evrything... so I put it back together and 80,000 miles later (200k miles now!) the motor still runs like a top, unsightly sludge and all. Go figure.

 

I don't have one on my car because American Muscle backordered it, but now I hear it is on the way!

I think it is questionable whether it is really "needed" but I like the idea of keeping that crap out of the intake, so I'm going for it.

I didn't realize it would collect that much oil though! I was planning to empty it at oil change time and put it in with the used oil; maybe I need to look at it more often than that and will have to store it somewhere until it goes back to Wally World with the rest of the used oil.

 

"My original question was why AREN'T you running one?...
Some of you guys may claim to have a 'mechanic's mind' but I would rather hear from engineers on this one."

GOOD POINT (above). What, if any, are the down sides from using an oil separator in the PCV line?

 

lol...coming from someone who deals with "engineers" on a daily basis I can tell you that the thought process of them being smarter than the mechanics is absurd. Engineers know things cause books tell them, while mechanics know things from experience. This goes for all fields.

 

Well then let's hear from the engineers who know how to handle the business end of a wrench as well as the text books.

 

Very very true.

 

This is info I got from an engineer who designs Ford motors. He shell remain anonymous of course, unless he would wish to share further.

"With critical components becoming smaller and smaller in the name of reducing parasitic losses -- friction, in cases like these -- I'd say blow-by such as this will become the norm (the 4.6L 3V as well as Chevy's V8's are notorious for this type of blow-by, too). Ford is only concerned with giving you 412 horsepower, making the engine, car and components last 150,000+ miles and warrantying said parts for however long the terms state. While a catch can would definitely help keep things clean, the oil blow-by's negative impact on your engine and components such as the intake are so negligible in terms of the big picture that Ford and other manufacturers just can't justify the cost, especially on a niche vehicle meant to fit a certain price target."

After hearing that I decided to save my money

 

I think its funny how oil seps come up for discussion about every 6-9 months. And the responses range from doubters to revelation to analysis/paralysis. We've got what, 3 sep threads going now over the last few months? lol

I got mine from BKU Motorsports who runs a race shop, has a Lightning race team, and is from a family of Ford Dealers. He hardly posts, but when you talk to him you know this guy isn't some hack.

Sadly we lost some great technical posts in the Labor Day 09 crash, but I saved a few notes. As you will read, the overdrafting of modern engines is simply to allow longer intervals between oil changes, regardless of piping the excess into the combustion chamber for the (negative) benefit of carbon caking.

You asked for it. This was a 6.09 response to a member who was having a drastic increase in PCV flow after installing cams. Here you go:

 

What big picture is he referring to? Ford profits?

It might be a niche vehicle to him and Ford, but its the ONLY hot rod I own. That makes it a majority vehicle in my life, not a niche vehicle.

I respectfully disagree. This much carbon at just 13k miles is not what I would call 'negligible' for an engine I want to keep for 100k and have it run at its full potential for all of those miles. And a lousy $50 bucks solves the problem.
But each their own.

 

Essentially yes. The question I had asked him was "Is a catch can necessary? And if so why doesn't Ford have it come standard?"

That was his response and it makes sense perfect sense.

They might be more necessary in that motor you posted Charlie, but unless we see pics of a torn down coyote its almost irrelevant

 

i ordered mine