GUESS I WAS RIGHT!
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Do oil catch cans work? - Engineering Explained
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The $25 one works if you add Stainless Steel Mesh/Wool to the round baffle inside. (It unscrews). I noticed what I collected made a big jump when I added this.
Do they work - yes.
Are they always needed or beneficial - no.
Depends on engine design.
Later DI designs like Hondas earth dreams moved the injector behind the valves vs centered on top shooting down so they still get a cleaning wash when using a specific pattern negating the buildup issue.
UD
Are they always needed or beneficial - no.
Depends on engine design.
Later DI designs like Hondas earth dreams moved the injector behind the valves vs centered on top shooting down so they still get a cleaning wash when using a specific pattern negating the buildup issue.
UD
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Originally Posted by UncleDave
Do they work - yes.
Are they always needed or beneficial - no.
Depends on engine design.
Later DI designs like Hondas earth dreams moved the injector behind the valves vs centered on top shooting down so they still get a cleaning wash when using a specific pattern negating the buildup issue.
UD
For sure some OE's handle it better than others... Ford/Mazda as an example. I'd still run one of these in any D.I. engine where there isn't a dual injection setup though. The less chance for crap across the valves the better. Working good on my cousins first gen Veloster which had to go in for valve cleaning under warranty when it was first new and hasn't since. It catches about 1/4 of the can full of oil every fill-up with gas she tells me.
Do they work - yes.
Are they always needed or beneficial - no.
Depends on engine design.
Later DI designs like Hondas earth dreams moved the injector behind the valves vs centered on top shooting down so they still get a cleaning wash when using a specific pattern negating the buildup issue.
UD
For sure some OE's handle it better than others... Ford/Mazda as an example. I'd still run one of these in any D.I. engine where there isn't a dual injection setup though. The less chance for crap across the valves the better. Working good on my cousins first gen Veloster which had to go in for valve cleaning under warranty when it was first new and hasn't since. It catches about 1/4 of the can full of oil every fill-up with gas she tells me.
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I definitely think with catch cans, the question isnt whether or not they work, its whether or not they matter.
I had the intake of my dads Corolla at around 280,000 miles trying to diagnose how sluggish it was, and I probably scraped enough oily wet carbon out of the intake tracts to fill up Rosie O'Donnell's mouth, it was horrific. The difference that made was night and day, it drove like an entirely different car once I got all of that junk out. I couldnt believe how much gunk I got out of that thing.
I had the intake off my 240sx at around 220,000 to replace the leaky hoses under the manifold, and I dont think I got enough carbon and crud out of it to literally fill a thimble. There was simply nothing there.
Would a catch can have mattered on the Corolla? Without a doubt, in my opinion. Would it have mattered on the Nissan? Not one bit. On most cars, I think they are nothing more than a solution looking for a problem.
I had the intake of my dads Corolla at around 280,000 miles trying to diagnose how sluggish it was, and I probably scraped enough oily wet carbon out of the intake tracts to fill up Rosie O'Donnell's mouth, it was horrific. The difference that made was night and day, it drove like an entirely different car once I got all of that junk out. I couldnt believe how much gunk I got out of that thing.
I had the intake off my 240sx at around 220,000 to replace the leaky hoses under the manifold, and I dont think I got enough carbon and crud out of it to literally fill a thimble. There was simply nothing there.
Would a catch can have mattered on the Corolla? Without a doubt, in my opinion. Would it have mattered on the Nissan? Not one bit. On most cars, I think they are nothing more than a solution looking for a problem.
Originally Posted by quint
I definitely think with catch cans, the question isnt whether or not they work, its whether or not they matter.
I had the intake of my dads Corolla at around 280,000 miles trying to diagnose how sluggish it was, and I probably scraped enough oily wet carbon out of the intake tracts to fill up Rosie O'Donnell's mouth, it was horrific. The difference that made was night and day, it drove like an entirely different car once I got all of that junk out. I couldnt believe how much gunk I got out of that thing.
I had the intake off my 240sx at around 220,000 to replace the leaky hoses under the manifold, and I dont think I got enough carbon and crud out of it to literally fill a thimble. There was simply nothing there.
Would a catch can have mattered on the Corolla? Without a doubt, in my opinion. Would it have mattered on the Nissan? Not one bit. On most cars, I think they are nothing more than a solution looking for a problem.
I disagree as mentioned in his other video where he says that OE's are aware of valve deposits being a problem and they don't like talking about it. I would agree with you on the engines that use PFI or PFI in addition to DI to combat this problem or in Mazda's case where they keep the valves at a higher temperature to deal with oil not able to form deposits as was mentioned here previously.
Here is the other video I referenced with Jason from Engineering explained where he touches on valve deposits in the video: https://www.youtube.com/watch?v=66C4YIiwRbM
I definitely think with catch cans, the question isnt whether or not they work, its whether or not they matter.
I had the intake of my dads Corolla at around 280,000 miles trying to diagnose how sluggish it was, and I probably scraped enough oily wet carbon out of the intake tracts to fill up Rosie O'Donnell's mouth, it was horrific. The difference that made was night and day, it drove like an entirely different car once I got all of that junk out. I couldnt believe how much gunk I got out of that thing.
I had the intake off my 240sx at around 220,000 to replace the leaky hoses under the manifold, and I dont think I got enough carbon and crud out of it to literally fill a thimble. There was simply nothing there.
Would a catch can have mattered on the Corolla? Without a doubt, in my opinion. Would it have mattered on the Nissan? Not one bit. On most cars, I think they are nothing more than a solution looking for a problem.
I disagree as mentioned in his other video where he says that OE's are aware of valve deposits being a problem and they don't like talking about it. I would agree with you on the engines that use PFI or PFI in addition to DI to combat this problem or in Mazda's case where they keep the valves at a higher temperature to deal with oil not able to form deposits as was mentioned here previously.
Here is the other video I referenced with Jason from Engineering explained where he touches on valve deposits in the video: https://www.youtube.com/watch?v=66C4YIiwRbM
as time goes on newer things get sorted out, but essentially the buyer is the beta tester in the real world. a few manufacturers are using both which though more complex works better. VW has both but not in the USA at this time. its said that in certain conditions port injection is better, but DI has its place as well. i have + had both VW + now older Audi, girlfriend had 2 earlier VW's all port injected + trouble free cars, but until VW brings dual systems to USA no sale here as turbo'd engines are generally worse for carbon issues.
Originally Posted by benjy
as time goes on newer things get sorted out, but essentially the buyer is the beta tester in the real world. a few manufacturers are using both which though more complex works better. VW has both but not in the USA at this time. its said that in certain conditions port injection is better, but DI has its place as well. i have + had both VW + now older Audi, girlfriend had 2 earlier VW's all port injected + trouble free cars, but until VW brings dual systems to USA no sale here as turbo'd engines are generally worse for carbon issues.
Yeah my aunts 2.0L TFSI Tiguan is already having issues at 80,000km with multiple cylinder misfire and VW told her the valves needed cleaning. I'm putting a can on that vehicle for her and we did the CRC GDI/Intake cleaner which worked and I reset the CEL already and will do it again regularly to keep the crap away along with a can to catch as much as possible. She was not happy that they quoted her $800 to fix it so soon in the vehicles life. It's also a royal PITA to do the CRC on that vehicle because of how the air ducting is routed.
as time goes on newer things get sorted out, but essentially the buyer is the beta tester in the real world. a few manufacturers are using both which though more complex works better. VW has both but not in the USA at this time. its said that in certain conditions port injection is better, but DI has its place as well. i have + had both VW + now older Audi, girlfriend had 2 earlier VW's all port injected + trouble free cars, but until VW brings dual systems to USA no sale here as turbo'd engines are generally worse for carbon issues.
Yeah my aunts 2.0L TFSI Tiguan is already having issues at 80,000km with multiple cylinder misfire and VW told her the valves needed cleaning. I'm putting a can on that vehicle for her and we did the CRC GDI/Intake cleaner which worked and I reset the CEL already and will do it again regularly to keep the crap away along with a can to catch as much as possible. She was not happy that they quoted her $800 to fix it so soon in the vehicles life. It's also a royal PITA to do the CRC on that vehicle because of how the air ducting is routed.
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Ok,
- first, it is a sponsored video to a website that sells automotive stuff, including catch cans.
- second, the test he cites didn't use any catch cans, they simply routed the PCV to an external source and plugged the intake manifold.
- third, the VW guy pretty much said it's more of a "feel good" thing because the junk he found was mostly water and fuel with very little oil.
I didn't see any proof, but rather an attempt at selling stuff. And some of these cans run between $300-$500! Wow, talk about capitalizing on fear.
- first, it is a sponsored video to a website that sells automotive stuff, including catch cans.
- second, the test he cites didn't use any catch cans, they simply routed the PCV to an external source and plugged the intake manifold.
- third, the VW guy pretty much said it's more of a "feel good" thing because the junk he found was mostly water and fuel with very little oil.
I didn't see any proof, but rather an attempt at selling stuff. And some of these cans run between $300-$500! Wow, talk about capitalizing on fear.
Catch cans are cheap enough, I put them on all of my vehicles. Some have caught a little oil, some have caught nothing. I don't use those expensive ones in the video. I use cheapos off ebay. They work equally as well. I also route it PCV > catch can > intake.
I bought a '96 Firebird 3.8L V6 several years ago that had a good bit of residue in the intake and on the valves. I installed a catch can and it would would have a oily residue inside the can after just a couple hundred miles. Replacing the PCV valve didn't help. I took my meth injection kit off my drag car and installed it on that car with a single, very small nozzle in the intake pipe about 3-4" ahead of the throttle body. I ran a mixture of 80% methanol, 20% distilled water by volume, and a button on the floorboard under the gas pedal so it activated only at WOT. Every time I drove the car, I made sure to put the pedal to the floor at some point for a few seconds at least. Over about 6 weeks, I dumped 5 gallons of that mixture through that engine. It did an excellent job of cleaning out the residue in the intake, runners, and valves. The plugs were also cleaner, and a bore scope through the plug hole showed a good bit of cleaning on the piston tops. The best part is that 5 gallons of mixture cost me less than $12. The meth injection kit however was $400+.
Not a street application, but on a 632ci BBC I wrench on, it has a 8qt wet sump with a vacuum pump and large catch can between the valve covers and the vacuum pump. The pump draws 10-11" of vacuum on the crankcase at 9500 rpm. After a single run down the dragstrip (burnout + 1/8th mile pass), it'll accumulate approximately 1/2 qt of oil in the catch can. After each pass, we just dump it back into the engine. That engine also runs on 0w-5 oil.
I bought a '96 Firebird 3.8L V6 several years ago that had a good bit of residue in the intake and on the valves. I installed a catch can and it would would have a oily residue inside the can after just a couple hundred miles. Replacing the PCV valve didn't help. I took my meth injection kit off my drag car and installed it on that car with a single, very small nozzle in the intake pipe about 3-4" ahead of the throttle body. I ran a mixture of 80% methanol, 20% distilled water by volume, and a button on the floorboard under the gas pedal so it activated only at WOT. Every time I drove the car, I made sure to put the pedal to the floor at some point for a few seconds at least. Over about 6 weeks, I dumped 5 gallons of that mixture through that engine. It did an excellent job of cleaning out the residue in the intake, runners, and valves. The plugs were also cleaner, and a bore scope through the plug hole showed a good bit of cleaning on the piston tops. The best part is that 5 gallons of mixture cost me less than $12. The meth injection kit however was $400+.
Not a street application, but on a 632ci BBC I wrench on, it has a 8qt wet sump with a vacuum pump and large catch can between the valve covers and the vacuum pump. The pump draws 10-11" of vacuum on the crankcase at 9500 rpm. After a single run down the dragstrip (burnout + 1/8th mile pass), it'll accumulate approximately 1/2 qt of oil in the catch can. After each pass, we just dump it back into the engine. That engine also runs on 0w-5 oil.
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Originally Posted by KrisZ
Ok,
- first, it is a sponsored video to a website that sells automotive stuff, including catch cans.
- second, the test he cites didn't use any catch cans, they simply routed the PCV to an external source and plugged the intake manifold.
- third, the VW guy pretty much said it's more of a "feel good" thing because the junk he found was mostly water and fuel with very little oil.
I didn't see any proof, but rather an attempt at selling stuff. And some of these cans run between $300-$500! Wow, talk about capitalizing on fear.
Each engine is different and if you look at the video clip from the VW mechanic it shows quite a bit of oil caught.
Is it necessary on all engines? No. Will it hurt on engines where they aren't using PFI or a dual PFI/DI setup? No. My aunts TFSI VW is going to be a test case like the Veloster is to see if the gunky valves re-occur.
Ok,
- first, it is a sponsored video to a website that sells automotive stuff, including catch cans.
- second, the test he cites didn't use any catch cans, they simply routed the PCV to an external source and plugged the intake manifold.
- third, the VW guy pretty much said it's more of a "feel good" thing because the junk he found was mostly water and fuel with very little oil.
I didn't see any proof, but rather an attempt at selling stuff. And some of these cans run between $300-$500! Wow, talk about capitalizing on fear.
Each engine is different and if you look at the video clip from the VW mechanic it shows quite a bit of oil caught.
Is it necessary on all engines? No. Will it hurt on engines where they aren't using PFI or a dual PFI/DI setup? No. My aunts TFSI VW is going to be a test case like the Veloster is to see if the gunky valves re-occur.
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Originally Posted by Linctex
Originally Posted by StevieC
my cousins first gen Veloster ............ It catches about 1/4 of the can full of oil every fill-up with gas she tells me.
ZOIKS!!!
Is it really THAT BAD?
Yes it is...
Originally Posted by StevieC
my cousins first gen Veloster ............ It catches about 1/4 of the can full of oil every fill-up with gas she tells me.
ZOIKS!!!
Is it really THAT BAD?
Yes it is...
Originally Posted by StevieC
Each engine is different and if you look at the video clip from the VW mechanic it shows quite a bit of oil caught.
Is it necessary on all engines? No. Will it hurt on engines where they aren't using PFI or a dual PFI/DI setup? No. My aunts TFSI VW is going to be a test case like the Veloster is to see if the gunky valves re-occur.
I watched the video. The top layer is the oil cough. Everything else is most likely water mixed with some fuel.
![[Linked Image]](https://www.bobistheoilguy.com/forums/attachments/usergals/2019/04/full-15440-31758-oil.jpg "[Linked Image]")
Each engine is different and if you look at the video clip from the VW mechanic it shows quite a bit of oil caught.
Is it necessary on all engines? No. Will it hurt on engines where they aren't using PFI or a dual PFI/DI setup? No. My aunts TFSI VW is going to be a test case like the Veloster is to see if the gunky valves re-occur.
I watched the video. The top layer is the oil cough. Everything else is most likely water mixed with some fuel.
Prius 3 guys sometimes fill the catch can twice a week
Definitely helps slow the destruction of the head gasket at that kind of volume
Definitely helps slow the destruction of the head gasket at that kind of volume
Originally Posted by KrisZ
Originally Posted by StevieC
Each engine is different and if you look at the video clip from the VW mechanic it shows quite a bit of oil caught.
Is it necessary on all engines? No. Will it hurt on engines where they aren't using PFI or a dual PFI/DI setup? No. My aunts TFSI VW is going to be a test case like the Veloster is to see if the gunky valves re-occur.
I watched the video. The top layer is the oil cough. Everything else is most likely water mixed with some fuel.
In that case... My Highlander caught a lot more actual oil and 0 water. The can was 1/4 full of straight oil in short order. It did slow a bit thereafter but it was still catching more oil that above.
Originally Posted by StevieC
Each engine is different and if you look at the video clip from the VW mechanic it shows quite a bit of oil caught.
Is it necessary on all engines? No. Will it hurt on engines where they aren't using PFI or a dual PFI/DI setup? No. My aunts TFSI VW is going to be a test case like the Veloster is to see if the gunky valves re-occur.
I watched the video. The top layer is the oil cough. Everything else is most likely water mixed with some fuel.
In that case... My Highlander caught a lot more actual oil and 0 water. The can was 1/4 full of straight oil in short order. It did slow a bit thereafter but it was still catching more oil that above.
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For a while, I considered installing a catch can(s) but finally decided against, because all my vehicles are port injected. Lots of port injected vehicles going 300,000+ miles without any modifications and without any performance or emissions problems. I actually believe that the oil mist going through the intake provides some upper cylinder lubrication... call me crazy
If the owners/operators of these engines would actually obey the OCI intervals (or exceed them), and ensure the proper oils are used, most, if not all of the problem would go away.
The VW guy cited in the video showed what basically amounted to something that looked like virgin motor oil coming out of the catch can. Hence, the issues are clearly occurring very early in the OCI cycle. What he captured were distillation products of virgin motor oil.
By changing oil less often, the exposure of the PCV to such products is reduced significantly as the crankcase isn't full of that virgin motor oil.
This is why this issue is mostly unheard of in engines which are maintained according to manufacturer's specs, which means doing OCI's at intervals that might shock people with 'old-fashioned' beliefs about OCI's. If this were a medical issue, it would be called 'iatrogenic', ie: an issue induced by the 'treatment' for the disease itself. The mindset that "more oil changes must be better" is extremely harmful.
Quote
I watched the video. The top layer is the oil cough. Everything else is most likely water mixed with some fuel.
Looks like distillates of virgin motor oil with a bit of a water/fuel/oil emulsion on the surface. I view the video as prima facie proof that oil changes should be performed as sparingly as possible on such engines.
The VW guy cited in the video showed what basically amounted to something that looked like virgin motor oil coming out of the catch can. Hence, the issues are clearly occurring very early in the OCI cycle. What he captured were distillation products of virgin motor oil.
By changing oil less often, the exposure of the PCV to such products is reduced significantly as the crankcase isn't full of that virgin motor oil.
This is why this issue is mostly unheard of in engines which are maintained according to manufacturer's specs, which means doing OCI's at intervals that might shock people with 'old-fashioned' beliefs about OCI's. If this were a medical issue, it would be called 'iatrogenic', ie: an issue induced by the 'treatment' for the disease itself. The mindset that "more oil changes must be better" is extremely harmful.
Quote
I watched the video. The top layer is the oil cough. Everything else is most likely water mixed with some fuel.
Looks like distillates of virgin motor oil with a bit of a water/fuel/oil emulsion on the surface. I view the video as prima facie proof that oil changes should be performed as sparingly as possible on such engines.
Translation: Does One Type of Poorly Engineered Catch Can Perform the Duties of Its Exaggerated Marketing On a Gasoline Engine?
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