What's with the oil catch cans?

[HSKR R/T]

Can't make this response to just one person. Engines should not have a pressurized system. Yes the EPA was around, and mandated PCVs. Beforehand, engines had down draft, or road draft tubes. They went down the back of the engine, where air passing by, sucked the fumes out. The PCV valves purpose, is to keep the engine running, because if the valve wasn't there, the engine would die from the major vacuum leak. At an idle, the valve stas closed, but as you hit the throttle, the vacuum drops, and the valve opens, sucking the fumes when the vacuum is low. As it is removing the fumes, it is also sucking atomized oil. Sucking that oil mist, is detrimental to the engine in the long run, because it causes carbon build up.It's not pulling that much oil, so it takes a long long time to do so. The catch can goes between the PCV, and the intake, where it catches that oil mist, slowing carbon build up, and yes prolonging engine life. The engine can easily go a couple hundred thousand miles without a catch can, but yes, the catch can will extend that life by more than that 400 miles.

Uh, lots of wrong with this post. Some correct statements, but mostly wrong.

 

[6of36]

Uh, lots of wrong with this post. Some correct statements, but mostly wrong.

What is wrong?

 

[HSKR R/T]

What is wrong?

Ugh, where to start.....

Engines should not have a pressurized system. Yes the EPA was around, and mandated PCVs. Beforehand, engines had down draft, or road draft tubes. They went down the back of the engine, where air passing by, sucked the fumes out.

As I already mentioned, PCV solenoids were in use well before EPA was even created. They serve the same purpose as the the crankcase evacuation system you mention that tire into the exhaust, and were more simple design and easier to maintain. The purpose is exactly as the name describes, positive crankcase ventilation. They use engine vacuum to suck air out of crankcase, from one valve cover, that is being pressurized by blowby, and into the intake. There is a fiktered air source on other side. The "positive" doesn't mean positive pressure. It actually puts negative pressire in the system which helps keep the piston rings sealed to limit blow by.

The PCV valves purpose, is to keep the engine running, because if the valve wasn't there, the engine would die from the major vacuum leak.

Wrong. The engine will NOT die if there isn't a PCV valve in place. You can unplug the vacuum line and engine will still run, the RPMs will just be higher, and PCM will have a hard time adjusting A/F ratio because of unmetered airflow. Might be slightly lean, until O2 sensors compensate, but the engine will not die.

At an idle, the valve stas closed, but as you hit the throttle, the vacuum drops, and the valve opens, sucking the fumes when the vacuum is low.

That is the exact opposite of how the PCV valve works. Vacuum is high at idle or when cruising at steady speed. And the vacuum holds the solenoid(not valve) open. At low vacuum when accelerating, the solenoid closes. PCV solenoids are designed for different vacuum amounts based on application. Some have lighter plungers so it takes less vacuum to open. Others have heavier plungers requiring more vacuum to open.


The rest is about hejonly thing you said that is true.

As it is removing the fumes, it is also sucking atomized oil. Sucking that oil mist, is detrimental to the engine in the long run, because it causes carbon build up.It's not pulling that much oil, so it takes a long long time to do so. The catch can goes between the PCV, and the intake, where it catches that oil mist, slowing carbon build up, and yes prolonging engine life. The engine can easily go a couple hundred thousand miles without a catch can, but yes, the catch can will extend that life by more than that 400 miles.

 

[TheWaterman83]

The "benefit" of lightening my wallet, voiding the warranty, and spending more time installing and periodically emptying it? Pass.

I take it you've never seen a modern motor's intake manifold interior in a high mileage motor? I agree if its a lease, don't bother. You won't see the benefit with something you only keep for 36k in miles. When I decided I was going to buy my truck out, that's when I bought it. I've seen a few modern motors intake manifolds at high mileage and the oil that comes out is pretty wild. Lets also think about what the design without the oil catch is: You're burning oil. You're burning oil mist AND water in your motor. I don't know about you but mechanics 101 teaches us that's not good.

Remember, the whole purpose of an oil vapor recirculation system is emissions. The EPA does not care about you slowly destroying your motor. All they care about is that you meet emissions like the good communist dictators expect you to. Oh your vehicle gets 50k less miles? Not their problem. The stuff these systems do to valve trains, pistons, etc. is pretty bad.

There's a reason why a lot of the emission-exempt vehicles (diesels) from 15 years ago just have the CV tube dump right onto the road. Also a reason why older cars just had one-way PCV valves. I don't necessarily think this is an eco-conscious way to do it. The oil catch can is definitely the way to go.

$200, $100 whatever it is. Some work, some don't. I know the output hose in my Mishimoto $200 can was bone dry when I checked. Also, which I did not know, the Mishimoto can has a threaded bung on the bottom of the can. There's some guys online that buy the correct hose barb, some hose, and a small valve and run it into the closest front wheel well. Emptying can be as easy as grabbing a mason jar, opening the valve, and then closing.

The reality is: If you bought a catch can and there is ANY oil in that output hose? You bought a crap catch can.

 

[6of36]

Ugh, where to start.....



As I already mentioned, PCV solenoids were in use well before EPA was even created. They serve the same purpose as the the crankcase evacuation system you mention that tire into the exhaust, and were more simple design and easier to maintain. The purpose is exactly as the name describes, positive crankcase ventilation. They use engine vacuum to suck air out of crankcase, from one valve cover, that is being pressurized by blowby, and into the intake. There is a fiktered air source on other side. The "positive" doesn't mean positive pressure. It actually puts negative pressire in the system which helps keep the piston rings sealed to limit blow by.



Wrong. The engine will NOT die if there isn't a PCV valve in place. You can unplug the vacuum line and engine will still run, the RPMs will just be higher, and PCM will have a hard time adjusting A/F ratio because of unmetered airflow. Might be slightly lean, until O2 sensors compensate, but the engine will not die.



That is the exact opposite of how the PCV valve works. Vacuum is high at idle or when cruising at steady speed. And the vacuum holds the solenoid(not valve) open. At low vacuum when accelerating, the solenoid closes. PCV solenoids are designed for different vacuum amounts based on application. Some have lighter plungers so it takes less vacuum to open. Others have heavier plungers requiring more vacuum to open.


The rest is about hejonly thing you said that is true.

I see I was wrong about the EPA being the one who made the law, because they came around in 1970, but it was environmental law.

When did PCV valves become mandatory?

In California, the PCV valve was mandatory on all new vehicles for 1961. By 1964, the majority of vehicles sold in the U.S. had one as standard equipment. It became mandatory on all vehicles in 1967.

I never said the engine should have positive pressure, the system is to remove positive pressure. They could have called it the Remove Positve Crankcase Pressure Valve. The PCV valve IS there to keep the engine running, when sucking engine gasses, because if you connect the hose directly to the valve cover, the engine will not stay running. It regulates vacuum loss. I wasn't saying that's the only thing keeping the engine running, but something has to restrict that vacuum loss. The vacuum closes the PCV. They will rattle around, with no vacuum, they rattle around with no vacuum, and suck shut with vacuum. The bottom opening at the valve cover is always open, the part that closes, is at the hose end. Try sucking on the hose end of a removed PCV valve.

 

[TheWaterman83]

I think I said this early but the reason that manufacturers don't make these systems in an OEM fashion is because they know 95% of the general public doesn't even know how to open the hood, let alone check their oil, and without a doubt, definitely let alone, empty an oil catch can.

There's just stuff that works. This is one of them. I think it just needs to be said that:

No, it will not increase HP.
No, it will not increase torque.
No, you will not likely notice some measurable difference in your motor/performance/etc.

The simple math states it will increase motor longevity over time.

 

[boogielander]

I take it you've never seen a modern motor's intake manifold interior in a high mileage motor? I agree if its a lease, don't bother. You won't see the benefit with something you only keep for 36k in miles. When I decided I was going to buy my truck out, that's when I bought it. I've seen a few modern motors intake manifolds at high mileage and the oil that comes out is pretty wild. Lets also think about what the design without the oil catch is: You're burning oil. You're burning oil mist AND water in your motor. I don't know about you but mechanics 101 teaches us that's not good.

Remember, the whole purpose of an oil vapor recirculation system is emissions. The EPA does not care about you slowly destroying your motor. All they care about is that you meet emissions like the good communist dictators expect you to. Oh your vehicle gets 50k less miles? Not their problem. The stuff these systems do to valve trains, pistons, etc. is pretty bad.

There's a reason why a lot of the emission-exempt vehicles (diesels) from 15 years ago just have the CV tube dump right onto the road. Also a reason why older cars just had one-way PCV valves. I don't necessarily think this is an eco-conscious way to do it. The oil catch can is definitely the way to go.

$200, $100 whatever it is. Some work, some don't. I know the output hose in my Mishimoto $200 can was bone dry when I checked. Also, which I did not know, the Mishimoto can has a threaded bung on the bottom of the can. There's some guys online that buy the correct hose barb, some hose, and a small valve and run it into the closest front wheel well. Emptying can be as easy as grabbing a mason jar, opening the valve, and then closing.

The reality is: If you bought a catch can and there is ANY oil in that output hose? You bought a crap catch can.

some people will spend $50 on a knock-off and think it'd work just fine, which may or may not be true.
but when they don't work well as the $200 option they knock the whole system saying it's a waste of money.

there's a reason why legit products are expensive and knock-offs are cheap: knock-off copy the designs and put no R&D into the stuff. Also I can't repeat this enough: there's a correct way of doing things and then there are mickey mouse ways of doing things. Expensive products backed by R&D are usually the correct way of doing things while cheap products backed by copying are usually the mickey mouse way of doing things.

 

[HSKR R/T]

some people will spend $50 on a knock-off and think it'd work just fine, which may or may not be true.
but when they don't work well as the $200 option they knock the whole system saying it's a waste of money.

there's a reason why legit products are expensive and knock-offs are cheap: knock-off copy the designs and put no R&D into the stuff. Also I can't repeat this enough: there's a correct way of doing things and then there are mickey mouse ways of doing things. Expensive products backed by R&D are usually the correct way of doing things while cheap products backed by copying are usually the mickey mouse way of doing things.

And then there are those companies who copy designs and charge more simply because of the name on the product. Or those companies who buy the same product, being sold cheaper with no brand name, but still charge more by slapping their name in the product. There are a lot of expensive products being sold by name brand companies that don't do anything other than put their name in a product that fits in their genre of products.

 

[HSKR R/T]

I see I was wrong about the EPA being the one who made the law, because they came around in 1970, but it was environmental law.

When did PCV valves become mandatory?

In California, the PCV valve was mandatory on all new vehicles for 1961. By 1964, the majority of vehicles sold in the U.S. had one as standard equipment. It became mandatory on all vehicles in 1967.

I never said the engine should have positive pressure, the system is to remove positive pressure. They could have called it the Remove Positve Crankcase Pressure Valve. The PCV valve IS there to keep the engine running, when sucking engine gasses, because if you connect the hose directly to the valve cover, the engine will not stay running. It regulates vacuum loss. I wasn't saying that's the only thing keeping the engine running, but something has to restrict that vacuum loss. The vacuum closes the PCV. They will rattle around, with no vacuum, they rattle around with no vacuum, and suck shut with vacuum. The bottom opening at the valve cover is always open, the part that closes, is at the hose end. Try sucking on the hose end of a removed PCV valve.

You still have PCV operation backwards. And your engine will still run without the PCV connected. The PCM will eventually compensate for the extra airflow. There is not enough vacuum loss to prevent the engine from running

 

[TheWaterman83]

some people will spend $50 on a knock-off and think it'd work just fine, which may or may not be true.
but when they don't work well as the $200 option they knock the whole system saying it's a waste of money.

there's a reason why legit products are expensive and knock-offs are cheap: knock-off copy the designs and put no R&D into the stuff. Also I can't repeat this enough: there's a correct way of doing things and then there are mickey mouse ways of doing things. Expensive products backed by R&D are usually the correct way of doing things while cheap products backed by copying are usually the mickey mouse way of doing things.

Oh for sure. I think forums like this are a great way for finding effective products. I've learned so much about the go-to stuff for these trucks on here. There probably is something cheaper than the Mishimoto that works just as well. But like you said, how low can you really go for a product that actually works? For something as well built as the Mishimoto you can't simply find for less than $100. It's pretty well made.

 

[boogielander]

And then there are those companies who copy designs and charge more simply because of the name on the product. Or those companies who buy the same product, being sold cheaper with no brand name, but still charge more by slapping their name in the product. There are a lot of expensive products being sold by name brand companies that don't do anything other than put their name in a product that fits in their genre of products.

true. that's why doing the homework individually is important.
or ask and listen to people who are in the industry and isn't afraid to call things out. those people are the ones who've seen a thing or two.


but still, do the homework first.

 

[boogielander]

Oh for sure. I think forums like this are a great way for finding effective products. I've learned so much about the go-to stuff for these trucks on here. There probably is something cheaper than the Mishimoto that works just as well. But like you said, how low can you really go for a product that actually works? For something as well built as the Mishimoto you can't simply find for less than $100. It's pretty well made.

exactly.
modding/ building trucks/ cars is not a cheap hobby. If one can't save and squeeze $100 or $200 over a period of time then imo he/ she got no business messing with the rigs.

 

[HSKR R/T]

exactly.
modding/ building trucks/ cars is not a cheap hobby. If one can't save and squeeze $100 or $200 over a period of time then imo he/ she got no business messing with the rigs.

I'm all about saving money where I can. Even if it's saving $100 on a catch can buying one with equal build quality but doesn't have the big name attached to it. The only time I will spend a little more for a part I could find cheaper elsewhere is to support a friends business, or a small business that makes specialty parts for the vehicle I am shopping for, as opposed to a larger company that sells products for multiple different vehicles/brands

 

[Rick3478]

I take it you've never seen a modern motor's intake manifold interior in a high mileage motor?

I have, and the intake manifold isn't what killed them.

I've seen a few modern motors intake manifolds at high mileage and the oil that comes out is pretty wild.

The key words are high mileage. Don't confuse cause and effect. Worn out rings allow lots of blow-by, and your catch can will fill up faster. Might slow down the gunk a bit (if you can keep up with it), but won't stop the cause.

 

[boogielander]

I'm all about saving money where I can. Even if it's saving $100 on a catch can buying one with equal build quality but doesn't have the big name attached to it. The only time I will spend a little more for a part I could find cheaper elsewhere is to support a friends business, or a small business that makes specialty parts for the vehicle I am shopping for, as opposed to a larger company that sells products for multiple different vehicles/brands

nothing wrong with saving money where you can.
for me there are few rules:
If it goes on the truck and plays any part in the truck's usability, no cheap items.
If it's made in China by Chinese companies, it does not belong on the truck.

"just as good" is never good.

 

[TheWaterman83]

I have, and the intake manifold isn't what killed them.

The key words are high mileage. Don't confuse cause and effect. Worn out rings allow lots of blow-by, and your catch can will fill up faster. Might slow down the gunk a bit (if you can keep up with it), but won't stop the cause.

Barring an acute catastrophic failure like a main bearing, broken rod, etc. you have literally no way of saying whether the motor died from that cause or not. At the end of the day, you do what you can to make things last. Quality fluids/oils, proper maintenance, not overmodding with performance parts, etc.

So what's the cause and effect here: Did the excess carbon build up on the rings cause more blowby in the catch can? Or did the absence of the catch can cause the carbon build up causing the rings to fail?

There's a lot more between the lines here.

Don't ever believe OEM "knows best." For example, your wallet may be super empty if you think the ZF 8 speed is fill for life, like Mopar says. Meanwhile, the folks at ZF in all the other vehicles its in say filter fluid change at 60k (100,000km).

 

[HSKR R/T]

nothing wrong with saving money where you can.
for me there are few rules:
If it goes on the truck and plays any part in the truck's usability, no cheap items.
If it's made in China by Chinese companies, it does not belong on the truck.

"just as good" is never good.

nothing wrong with saving money where you can.
for me there are few rules:
If it goes on the truck and plays any part in the truck's usability, no cheap items.
If it's made in China by Chinese companies, it does not belong on the truck.

"just as good" is never good.

Certain things that's true, and I can agree with, other things it's just something people say to justify spending as much as they did on said part. If you really looked into the manufacturing proceas and where everything is made, you might be surprised on where some of the items you buy are made.

Id be willing to put money on the Mishimoto catch and being made in China. The Mishimoto website says they have facilities in China. Just because it carries the Mishimoto name doesn't mean it's any better quality than any other Chinese catch can. It just means you paid more because of the name.

As you said, do some research. This is where I will spend more for hand made parts from companies like Vice Design, Shifts and Grins, Wicked Bumpers(local place my bumper came from)......... just ordered a tubular transmission cross member from a one man shop for my Dakota.

 

[boogielander]

Certain things that's true, and I can agree with, other things it's just something people say to justify spending as much as they did on said part. If you really looked into the manufacturing proceas and where everything is made, you might be surprised on where some of the items you buy are made.

Id be willing to put money on the Mishimoto catch and being made in China. The Mishimoto website says they have facilities in China. Just because it carries the Mishimoto name doesn't mean it's any better quality than any other Chinese catch can. It just means you paid more because of the name.

As you said, do some research. This is where I will spend more for hand made parts from companies like Vice Design, Shifts and Grins, Wicked Bumpers(local place my bumper came from)......... just ordered a tubular transmission cross member from a one man shop for my Dakota.

i know certain things are made in the same factory in china but carries different prices. however, most of the time big brand names do have some kind warranty or protection than those aliexpress/ ebay deals. when people pay a premium they are not only paying for the name, but also the whole after-sale services and even access to replacement parts.

every item i put on my truck is fully vetted, from country of origin to functionality. that's why i avoided mishimoto. When it comes to the truck money is no object. Heck, even the bolts and nuts that I use for my bed rack are all certified for strength and corrosion resistance and not generic household item, and costed me $180-ish extra because that kind of strength is exactly what I need for the stuff I do with the truck. point is, some people are ok with saving money here and there when modding, but for some proven reliability, longevity, and functionality is more important than a mere $100 or $200 difference.

 

[HSKR R/T]

i know certain things are made in the same factory in china but carries different prices. however, most of the time big brand names do have some kind warranty or protection than those aliexpress/ ebay deals. when people pay a premium they are not only paying for the name, but also the whole after-sale services and even access to replacement parts.

every item i put on my truck is fully vetted, from country of origin to functionality. that's why i avoided mishimoto. When it comes to the truck money is no object. Heck, even the bolts and nuts that I use for my bed rack are all certified for strength and corrosion resistance and not generic household item, and costed me $180-ish extra because that kind of strength is exactly what I need for the stuff I do with the truck. point is, some people are ok with saving money here and there when modding, but for some proven reliability, longevity, and functionality is more important than a mere $100 or $200 difference.

Line I said for some things I agree. For a catch can.......buy the cheapest "quality" piece that does the job it's meant to. I'd put my $50 Amazon catch can up against any $150+ name brand one

 

[boogielander]

well anyways some people are fine with "good enough" and some others want to put nothing but the best. all personal choices.

but yeah catch cans are put in for the peace of mind and not to gain HP or anything.