pcv catch can

[rslifkin]

It's not a "problem", per se, as things will still function correctly unless they gunk up very badly. However, it's certainly not ideal, and removing the oil won't hurt. That said, I haven't bothered with a catch can on my Jeep, although it does pull a decent bit of oily mist through the PCV (but doesn't seem to produce much gunk).

 

[mechtech2]

Factories are not going to install something that requires customer maintenance every couple of weeks or months!
They have to have a system that will work without touching it for 50,000-100,000 miles.

But to think a catch can does no good is silly.
Once again, throttle bodies, intakes, valves, and combustion chambers are benefited. No or less gunk!
When you empty your reservoir, think about where that stuff could have ended up!

 

[dailydriver]

Originally Posted By: mechtech2
Once again, throttle bodies, intakes, valves, and combustion chambers are benefited. No or less gunk!
When you empty your reservoir, think about where that stuff could have ended up!


^^^THIS is why I installed one, YES even while using one of the lowest volatility oils on the market!

 

[SteveSRT8]

There are some of us with reading comprehension issues. I'm not disputing whether or not it does anything.

I have an 850 HP stroker Chevy BB boat motor that uses one, and it does collect oil. But it's supercharged, so it has an excuse for a little extra blow by!

My point is: is it NEEDED? I would say the overwhelming numbers of fine running cars on the road that do not have one proves it is not needed.

Others may think differently.

And at a drag strip meet in Bradenton where we rented the track for an entire day we ran dozens of Mopars all day long. Many of them are devout catch can users and not a one was able to get any better ET or trap than me even with minor mods!

 

[ltslimjim]

^I'd say the 'minor' issues that could/do develop is only related to idling and light acceleration. At the track it doesn't matter.

 

[rslifkin]

^ Exactly. It's not necessary in the sense that things will function just fine without it. However, it certainly doesn't hurt anything, and can reduce the risk of gunked up throttle body components, etc.

 

[ahoier]

That's a neat concept. My 88 Dodge Aries is actually "speced" to have a "brather element" that goes inside the air box, which appears to be "above" the manifold.....which I guess, has the job of an extra filter, as well as possible oil-absorbent.....but when I bought the vehicle, it did not have one in the air box. Debating whether to get one or not....eh, it's ran fine thus far, and I'm not tripping any CELs since I got my vacuum lines fixed, and I'm no longer running rich either.

Last month I went and took apart the air box in attempt to find the PCV valve lol, and the inside of the air box was dry.....so if there happens to be "blow by" it can't be too much....

 

[Shannow]

Moving desks this week, and came across this article in my stash of junk...found it online. at link below.

Interesting comment regarding VIIs and turbocharger deposits versus straight weigh non VII oils...made me think that maybe RLI's DI friendly oils may in fact be onto something re intake deposits.

http://www.pdfebook4u.com/download/Crank...WZpbHRlcnMucGRm

Quote:
On older, naturally aspirated engines
the result is minor, possibly slightly dirtier
combustion and earlier fouling of injectors.
On turbocharged engines the dirty, oily mist
can coat impeller blades, foul aftercoolers,
and significantly shorten engine life. A
source in the industry says that single-
weight oils tend to pass directly into the
combustion chamber, whereas multi-grade
oils, which are specified for some modern
turbocharged engines, contain a butyl vis-
cosity enhancer, which is more likely to
stick to turbo components.

 

[SOHCman]

Originally Posted By: ahoier
That's a neat concept. My 88 Dodge Aries is actually "speced" to have a "brather element" that goes inside the air box, which appears to be "above" the manifold.....which I guess, has the job of an extra filter, as well as possible oil-absorbent.....but when I bought the vehicle, it did not have one in the air box. Debating whether to get one or not....eh, it's ran fine thus far, and I'm not tripping any CELs since I got my vacuum lines fixed, and I'm no longer running rich either.

Last month I went and took apart the air box in attempt to find the PCV valve lol, and the inside of the air box was dry.....so if there happens to be "blow by" it can't be too much....


I think normally on systems like that, the airbox side of the breather system won't have oil residue, but the PCV valve side will. The "breather" simply filters air being drawn into the crankcase which is then pulled through the PCV valve (usually on a valve cover) and then pulled into the intake.

You may not see oil on the breather side, but I bet you will on the pcv side. If you do end up getting oil on the breather side one day, it may be an indication of "excessive" blow by due to something like worn piston rings.

 

[SteveSRT8]

Since the PCV system needs a source of very clean air to replace what it vents from the crankcase a filter is a GOOD idea!

It is notable that many of the smaller 4 bangers I've seen had a baffled separator type arrangement in the valve cover where the PCV plumbed in.

Many of the larger engined cars do not use this excellent idea and they need it even more.

 

[rslifkin]

My engine has baffles in the valve covers to try to keep oil out of the PCV, but they're not 100% effective, as the dipstick level will drop a hair (probably about 4 ounces of oil) any time I make the 350 mile run between home and college. It seems to only come into play at sustained highway speeds (light load at over 1500 rpm). Under other conditions, including sustaining 3k+ RPM with heavy throttle on a track, it doesn't use a drop of oil.

 

[dvldoc]

Is this a crazy thought for a catch can? I currently have a very nice DIY one using air compressior air oil seperator this a foam element in it.

But could you just not use a remote oil filter like this with a little bit of steel wool or foam in the middle to do the same thing?

Seems like it should work just like one of these,

Just been wondering would that be as effective, not to mention simple to empty out or even change to a new filter. For those of use who got a bunch lying around seems like a good ideal. Or I could just be wrong.

 

[mechtech2]

Sure, you could make that work.
Extend the inlet from the crankcase lower, and have the outlet to the manifold high.
Ditch the foam inside. Steel wool can work, or leave it empty.

BTW:
The reason for possibly reversing the common air/water separator flow is simply because of the inlet outlet heights.
WE want the 'arrow' pointing to the engine.