Jump to content

Oil catch can?

C25A1guy

By C25A1guy
in Engines & Drivetrain

 Share

Recommended Posts

DanMan_S Enthusiast

DanMan_S

Posted
Posted (edited)

The technical term for what a "catch can" does is coalesce. The function is to remove liquids saturated into a flow of a gas.

 

Air Compressor systems have various methods to coalesce as do aircraft air conditioning/pressurization systems.

 

The simplest form of a coalescing device is an expansion type that allows the saturated gas to cool and slow. This allows the liquid vapor to form into droplets that stick to the chamber walls. These types are commonly seen for air compressor systems, with a clear bowl and drain valve. They are effective, but leave room for improvement.

 

When you add a type of baffle or labyrinth path for the gas to the above chamber, it increases the efficiency in removing liquid. The changes in direction allow inertia to force contact of droplets, formed from expansion, with the chamber walls. Centrifugal separators also rely on the inertia of the droplets to go to the outer wall because they are heavier than the gas. Centrifugal designs are difficult to make efficient with low flow rates.

 

Filter type coalescing systems are most often a combination of the above designs. They are almost always combined with expansion types. In many cases, labyrinth design is combined in at least a minimal way. Large airplanes use a type of filter, along with an expansion chamber to coalesce water out cabin air before it is sent to the cabin. The filter is simply a surface for the liquid droplets to adhere to. In these airplane a/c systems, it is a fabric stretched over a conical screen, in a larger cylindrical chamber (can). You often see a filter added to those "water separators " in compressor lines. This is not really for particulate removal, although it will do that. It is to provide more surface for droplets to adhere (coalesce).

 

The liquid in a crankcase vent flow will contain a significant amount of water vapor along with the oil vapor . This is condensation formed during cooling in the crankcase.

 

Excellent post!! My engineering firm does some CFD design of filters & separators for different pipeline applications, so I always get abit annoyed when people call the technology snake oil in a automotive application. As I have detailed CFD results and physical testing data to say otherwise, there is no magic to it, just basic thermodynamics and fluid dynamics.

Edited by DanMan_S
  • Replies 1.9k
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

ToesonTheNose
ToesonTheNose

Here at RX now they are doing a video install on my truck

Jay700
Jay700

My dealership said my catch can wasn't needed and wouldn't catch anything. I opened it in there shop after 2,000 miles and let it run on the floor. Lol

fondupot
fondupot

So, I added a second output fitting to my Original RX catch can. I had been emailing with the RevExtreme folks about the benefits of a dual output can, and they were gracious enough to send me the par

Posted Images

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted (edited)

I've got oil in my can after a 600 mile drive (and a little water too) - that's enough proof for me! :cheers:

 

post-65085-0-43377900-1427030773_thumb.jpg

post-65085-0-43377900-1427030773_thumb.jpg

Edited by Jsdirt
Spurshot Senior Enthusiast

Spurshot

Posted
Posted (edited)

 

Excellent post!! My engineering firm does some CFD design of filters & separators for different pipeline applications, so I always get abit annoyed when people call the technology snake oil in a automotive application. As I have detailed CFD results and physical testing data to say otherwise, there is no magic to it, just basic thermodynamics and fluid dynamics.

 

Come on Dan...CFD is snake oil. :lol: jus yankin your chain....

Edited by spurshot
Spurshot Senior Enthusiast

Spurshot

Posted
Posted

I've got oil in my can after a 600 mile drive (and a little water too) - that's enough proof for me! :cheers:

 

 

 

Looks like a lot of water and a little oil.

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

Yeah, -40°F wind chills will do that. :) Will be darkening up in the coming months ... I HOPE. Weather has been galactically craptastic this year ...

Spurshot Senior Enthusiast

Spurshot

Posted
Posted

Yeah, -40°F wind chills will do that. :) Will be darkening up in the coming months ... I HOPE. Weather has been galactically craptastic this year ...

 

You guys have had more than your share of it....

Silverado-Hareek Senior Enthusiast

Silverado-Hareek

Posted
Posted

I was draining about 6 oz of an oil/water mixture back in winter every 650 miles. It's down to about 2 oz over the same mileage now in the warmer spring weather.

 

 

Sent from my iPhone using Tapatalk

Silverado-Hareek Senior Enthusiast

Silverado-Hareek

Posted
Posted (edited)

The good news: I did the BG induction service yesterday and the truck seems to be running great afterwards, no issues so far *knocks on wood*

 

The bad news: I could not get before and after pictures of the valves. The way the intake is designed on these engines, you can't get the borescope in there because of all the bends and turns. We would have had to remove the intake manifold to see the valves and I wasn't about to do that on an engine with only 15k miles.

 

So the catch can debate will have to rage on. I will say I have not really noticed much of an improvement with the truck as others have reported. It honestly wasn't really running bad before I did the service, I just wanted to get in before 15k miles to take advantage of BG's warranty. So if guys without catch cans are noting an improvement in performance after the service and I'm not noticing much of anything, I'd argue that's evidence in favor of the catch can doing what people say it should be doing....keeping the valves clean. I only had 11,500 miles on the truck when I installed the catch can so there wasn't much time for a lot of build-up to happen and dramatically affect performance, although I don't doubt that some buildup did occur and the service yesterday took care of it.

 

 

EDIT: Forgot to add it was about $78 in materials and $117 in labor for the BG service so $195 total. You have to get your oil changed as well afterwards so factor that into the total if you're considering doing this service.

Edited by Silverado-Hareek
GuyGene Enthusiast

GuyGene

Posted
Posted (edited)

Whew boys, I spent he whole morning reading all the posts! Me old haid is spinning. Here's my conclusion, correct me if I'm wrong. I thought I was one time...

 

Which truck maker does not use direct injection? If none, I'll keep my 13 year old truck and keep fixing what breaks as needed.

 

I have come to loathe direct injection engines. What a stupid engineering system! Valves getting that gunked up because of it?!? Somebody mentioned Toyota developed a system to send some fuel over the valves to keep them clean. So, makers know this is a serious problem.

 

I'm wanting a new truck, but have decided to try my best to not get direct injection.

 

Ok boys, tell me wha' I'm missing.

Edited by GuyGene
Jon A Senior Enthusiast

Jon A

Posted
Posted

Well, direct injection allows you to have more power, better mileage and better emissions. The first two are good to have for the consumer, the last one is why you're going to have trouble finding any engine that isn't direct injected in a year or two. Every improvement comes with some sort of side effects, learning to deal with them is the best solution. Unless you don't mind driving antiques (or "classics") the rest of your life.

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

It seems the insatiable quest for "clean air" & fuel mileage has caused more problems to our vehicles (and our country .. but that's another topic for another day ...) than good. I guess clean air trumps quality. Why not? In this day and age animal's lives trump human life ... :nonod:

 

 

Yet, I still have asthma with all this clean air around me .... :rolleyes:

  • Like 1
Jon A Senior Enthusiast

Jon A

Posted
Posted

Didn't you know CO2 causes asthma now? It's much deadlier than it used to be. It's the "new science" from the religious left. :banghead:

kzinge1 Enthusiast

kzinge1

Posted
Posted (edited)

Installed my Elite Engineering can a couple weeks ago. Very nice quality, easy install and good price. Checked it after 50 miles and already has some oil in there. Will check again after about 500 miles.

 

d2e20776-bd2a-453c-8056-a5d27af43f08_zps

Edited by kzinge1
  • Like 1
chevy2tuff2006 Enthusiast

chevy2tuff2006

Posted
Posted

Installed my Elite Engineering can a couple weeks ago. Very nice quality, easy install and good price. Checked it after 50 miles and already has some oil in there. Will check again after about 500 miles.

 

d2e20776-bd2a-453c-8056-a5d27af43f08_zps

Nice have the same setup but one question. Do you hear a sound like a vacuum leak coming from your can.... with the hood shut walk by that corner of the truck with the engine running does it sounds like a vacuum leak. I have this and I'm wondering if its just the air inside of somewhat empty can making the vacuum leak sound or if I have a hose that has a hole in it or one of my elbow in the can leaking?

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

If you had a vac leak big enough to hear, you'd more than likely have a check engine light on, along with some very poor running.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • garagerog
      Low fuel pressure after installing new fuel pump

      By garagerog · Posted

      Replace the fuel pump with an OEM AC-Delco.
    • Gilkey96
      Low fuel pressure after installing new fuel pump

      By Gilkey96 · Posted

      Hello, first time posting here. I have an 03 Chevy 1500HD with the 6 liter gas engine. The truck ran fine until the fuel pump died on me and had to get it towed. Replaced the fuel pump with a precision pump from O’rileys and changed the fuel filter while I was there. The truck will run and drive now but it wants to idle around 500 rpm when in drive and it tries to stall if you touch the gas. It drives fine though, just doesn’t want to idle. Put a fuel pressure gauge on the rail and only have 50 psi. I guess these trucks should have 55-62 psi to run right. I thought the regulator might be the issue because when I would unplug the vacuum hose it jumped to 56 psi. Replaced the regulator and no change. The only thing I can think of is that I was sold a faulty fuel pump. Any help would be appreciated because I’d rather not have to take the bed off again if I don’t have too. Thank you!
    • diyer2
      AFM Experience

      By diyer2 · Posted

      I've been wrenching on GM trucks for 17 years. And I need to get something off my chest because it's been weighing on me for a long time. After all that time, all those motors, all those people standing in my bay, I've figured out there are really only two kinds of owners. The ones who already know about this. And the ones who are about to find out the hard way. A guy came into my shop a few weeks back in a 2018 Silverado 5.3. Sharp guy, maybe 35. Knew his truck cold. He'd been on the forums, read the threads, done his homework. He only rolled in so I could double-check a little module he'd already plugged in himself. Wanted a second set of eyes on it. Ten minutes, in and out, drove off happy. Two days later, a completely different story walked through the same door. Older fella this time, in a 2016 Sierra. Gorgeous truck, clearly babied, not a scratch on it. Wedding ring. Looked like a guy who took care of his stuff. He was in because his engine had started knocking on the way to work. And by the time I got the valve cover off, I already knew it was too late. Lifter collapsed. Cylinder 5. Camshaft chewed up. The whole top end shot. Same kind of truck. Same motor. Same roads, probably the same dealer. The only thing separating those two men was information. I've been at this since 2008, and I've worked on everything GM puts out. Silverados. Sierras. Tahoes. Yukons. Suburbans. Escalades. The 5.3 and the 6.2. Doesn't matter which badge is on the tailgate. They all carry the same problem. So here's the information one of those guys had and the other one didn't. It's called Active Fuel Management. AFM. GM started building it into their V6s and V8s back in 2007 to squeeze out a little better mileage on the highway. Maybe a mile or two a gallon. All to hit government fuel economy numbers. The way it works, the motor quietly shuts down half its cylinders when you're just cruising along. And the little lifters that pull that off have a tiny pin inside them that's constantly clicking in and out. Lock, unlock, lock, unlock. Hundreds of times a drive. Thousands of times a week. Eventually one of those pins wears through. The lifter drops. And it starts grinding the camshaft down like a chisel on butter. And what nobody tells you is that the shudder you feel around 40 or 50 mph? That's the system cycling. Every single time. Here's what really gets me. The pre-2007 trucks, the ones without AFM, they're bulletproof. I've got customers still daily driving them with 260,000 miles on the odometer. Not a problem in the world. GM took a perfectly good motor that would have lasted a lifetime and bolted this system onto it. And it is wrecking engines that should have run forever. The guys who hang around the forums already know all of this. So do the techs. They handled this years ago. They didn't sit around waiting for the dealership to mail them a warning letter, because that letter is never coming. It's the guys who figured somebody would've told them who end up on my lift. And I want to be clear, because this part matters. Maintenance has nothing to do with it. I've torn down motors with barely 30,000 miles on the clock. I pulled apart a Tahoe last summer with 24,000 on it. Practically a brand new truck. Owner had it less than a year. Spotless oil. Best synthetic money can buy, changed early every time. Made no difference. I've seen guys with full dealer records, every interval stamped. Made no difference. The oil changes were never the problem. The pin was. And no amount of babying that truck stops that pin from cycling every single time you drive. That's the part that eats at me. These are good motors. Take the AFM out of the equation and a 5.3 or a 6.2 will run 300,000 miles and never blink. So a few years ago I started telling every single owner who comes through my doors the exact same thing the smart guys already knew. Get yourself a FullForce disabler. It plugs right into the port under your dash. Couple of seconds and you're done. It just tells the computer to leave every cylinder running, full time. No more cycling. No more beating those lifters back and forth every time you turn the key. It doesn't reprogram anything. Doesn't touch your tune. And unplug it before a dealer visit and there's absolutely zero trace it was ever installed. I've had customers come back at 40,000, 60,000, 80,000 miles after I put one in. Zero issues. The trucks run smoother. And the lifters aren't getting beaten to death every single drive. I won't sit here and tell you it's magic. A lifter that's already damaged is a lifter that's already damaged, and this won't un-ring that bell. But it takes away the one thing causing all that wear in the first place. That's the whole game. You don't need a five-thousand-dollar delete. You don't need an expensive tune. You don't need to tear anything apart. You just need to stop the cycling. I'm not writing this for any company. I'm writing it because I'm tired of watching the guys who didn't know pay four and five figures for it. I'm tired of being the guy who has to break the news. I'm tired of knowing that the guys who did know fixed the whole thing for the price of a tank of gas, and the only difference was that somebody told them first. If you drive a Silverado, Sierra, Tahoe, Yukon, Suburban, or Escalade from 2007 or newer with a V6 or V8, you've got AFM. You've got those lifters, and they're cycling every single time you drive. So be the guy who already knew. Not the one I'm scraping metal out of next month. EDIT: A bunch of folks asked, so here it is. The one I put my faith in is FullForce. This is where to find it: https://www.tryfullforce.com/products/fullforce™-afm-dfm-disabler They back it with a 60-day guarantee too. I've handed out more than I can count and not one's ever come back to me. Not one. See less
    • Atlas
      Wow I'm in a pickle. (Broke down truck) and a story.

      By Atlas · Posted

      Thanks for following along. I'm not author material, my tenses are all over the place and an editor would have a heck of a time cleaning up after me. Reading and writing is still a fun pastime though.   My new scanner came in yesterday, wow, where the heck has this thing been?! It connects right up to the Blazer, there's all kinds of bidirectional tests like EGR activation and percentage, toggle the fuel pump relay, EVAP purge valve, IAC control, AC relay, reset the transmission's adaptive learning, toggle shift solenoids and TCC lockup, and I can reset fuel trims with the click of a button...all things I could have used over the last 60 days!   It's also telling me there is a stored code in the ABS module for front left wheel sensor open and something about the brake switch. The ABS dash light works. It illuminates normally during the self-test at key on/ start and that's it. I cleared the codes and will see if they set when I take it out later. That, and I'm going to get (hopefully) real data on timing and cam ******. The PID's are there.   I connected the tool to my truck...holy smokes. Newer vehicles make early OBDII vehicles look like 8-bit, pixelated, early Nintendo stuff. This? This is like wearing 3D virtual reality goggles playing one of those elaborate, cinematic video games with seasons and plots in comparison. There are SO MANY modules and SO MANY tests and SO MUCH data. There's a scanner sequence for filling the coolant...   End of the day, it's a tool with way more power than I need, but the versatility to do old and new is there (and I need an adapter to connect it to my OBDI Camaro). It will allow me to do the first pass of diagnosis when out-of-warranty vehicles need help, and it will enable more DIY maintenance like brake system bleeding, ABS bleed, etc. I probably over-bought here, but, mission is accomplished.   Enjoy your Sunday...I need to shut this machine down and go get ready for the week ahead.
    • MORSNO
      Which 2027 engine will you choose?

      By MORSNO · Posted

      Not that I've read, after all the issues they've had in the past I'm pretty sure they learned their lesson. 

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...