I would like to start a NEW catch can post for all to follow.

Jettech1 · February 2, 2023

9 hours ago, customboss said:

If these engines NEEDED catch cans GM would have installed them.

I totally get everything you said and agree with most of it. But GM actually did build in oil/air separators into the valve covers to prevent the oil in a gaseous state from entering the intake. The way I look at an external oil separator is basically a redundant system to help trap what the valve cover system is not able to. Kind of like the old Amsoil dual oil filter setup that was common 20 plus years ago, perhaps it still is today I don't know. But what I do know is that a catch can works, and is to me a second line of defense that only helps keep your intake clean along with the backside of the valves. I can't think of one downside to it. Is it masking a problem? I don't think so. From the research I've done, there are so many factors involved that it really doesn't make any sense to try and narrow each one down. Either way, it works, it gets oil in it, I drain it out, and that's just less oil in my intake. Pretty much bottom line.

Grumpy Bear · February 2, 2023

7 minutes ago, Jettech1 said:

I totally get everything you said and agree with most of it. But GM actually did build in oil/air separators into the valve covers to prevent the oil in a gaseous state from entering the intake. The way I look at an external oil separator is basically a redundant system to help trap what the valve cover system is not able to. Kind of like the old Amsoil dual oil filter setup that was common 20 plus years ago, perhaps it still is today I don't know. But what I do know is that a catch can works, and is to me a second line of defense that only helps keep your intake clean along with the backside of the valves. I can't think of one downside to it. Is it masking a problem? I don't think so. From the research I've done, there are so many factors involved that it really doesn't make any sense to try and narrow each one down. Either way, it works, it gets oil in it, I drain it out, and that's just less oil in my intake. Pretty much bottom line.

Ah, belt and suspenders guy. :rolleyes: Think I agreed earlier that it hurts nothing to run a can. I haven't changed my mind. That said it there a reason that this same principle could not be applied to finding the source? What does it hurt to look? I think that is the thrust of @customboss comments.

This is the wife's motor at roughly 80K miles. Problem here was that this motor uses an internal orifice CCV system that absolutely precludes the fitment of a catch can in its OEM form. So, what is a fella to do? We did as @customboss suggested. Ran down the cause. fixed it. The next manifold pull at roughly 160K. Clean inside. Still used oil but.... not fouling the valves. Just a thought. Feel free to ignore it.

Jettech1 · February 2, 2023

@customboss Have I got a "stupid" story for you. I owned a 2021 Ford Escape SE with the 3 cylinder turbo engine in it that was both port and DI. I installed a catch can on that engine. Talk about stupid right?? Anyhow I use to get an ounce or so every couple thousand miles that I would drain from the catch can. All I was doing was keeping that oil out of the intake. Not overly "stupid" in my opinion but hey, I've done a lot of "stupid" stuff in my days....Made me feel good knowing that oil was not collecting in my intake and I do love a clean engine. Inside and out!

Jettech1 · February 2, 2023

9 minutes ago, Grumpy Bear said:

Ah, belt and suspenders guy. Think I agreed earlier that it hurts nothing to run a can. I haven't changed my mind. That said it there a reason that this same principle could not be applied to finding the source? What does it hurt to look? I think that is the thrust of @customboss comments.

This is the wife's motor at roughly 80K miles. Problem here was that this motor uses an internal orifice CCV system that absolutely precludes the fitment of a catch can in its OEM form. So, what is a fella to do? We did as @customboss suggested. Ran down the cause. fixed it. The next manifold pull at roughly 160K. Clean inside. Still used oil but.... not fouling the valves. Just a thought. Feel free to ignore it.

Belt and suspenders always Grumpy. It's all good. I like debate and learning from others as always!

Dr1ft3r · February 2, 2023

Just be careful using a catch can if you live in very cold areas. I've read forum posts about the cans freezing and causing a total block of the system causing engine gaskets to blow out. That pressure has to go somewhere, it will find the weakest link.

My last DI engine was a Lexus RCF and I drove it like I stole it for 80k miles. No catch can and no performance issues at all. I read that regularly changing fuel brands was good for keeping the valves cleaner since different brands use different detergents. So, I usually used a different brand every time I filled the tank. I didn't care about top tier gas and rarely used it. But I did require premium fuel (91+ octane) if that matters.

That's what I'll be doing in this truck too. I don't doubt the science. But I'm regularly in extreme cold during the winter (-20+) and don't want the hassles and potentially huge problems of using a catch can.

Jettech1 · February 2, 2023

6 hours ago, Dr1ft3r said:

Just be careful using a catch can if you live in very cold areas. I've read forum posts about the cans freezing and causing a total block of the system causing engine gaskets to blow out. That pressure has to go somewhere, it will find the weakest link.

My last DI engine was a Lexus RCF and I drove it like I stole it for 80k miles. No catch can and no performance issues at all. I read that regularly changing fuel brands was good for keeping the valves cleaner since different brands use different detergents. So, I usually used a different brand every time I filled the tank. I didn't care about top tier gas and rarely used it. But I did require premium fuel (91+ octane) if that matters.

That's what I'll be doing in this truck too. I don't doubt the science. But I'm regularly in extreme cold during the winter (-20+) and don't want the hassles and potentially huge problems of using a catch can.

That's a great point you bring up concerning extreme cold temperatures. I've skimmed over a few articles concerning that but don't have any actual real world knowledge about it. I too think I would be skeptical about using one from what you're saying. Excellent point and thank you for bringing this up.

customboss · February 2, 2023

9 hours ago, Jettech1 said:

@customboss Have I got a "stupid" story for you. I owned a 2021 Ford Escape SE with the 3 cylinder turbo engine in it that was both port and DI. I installed a catch can on that engine. Talk about stupid right?? Anyhow I use to get an ounce or so every couple thousand miles that I would drain from the catch can. All I was doing was keeping that oil out of the intake. Not overly "stupid" in my opinion but hey, I've done a lot of "stupid" stuff in my days....Made me feel good knowing that oil was not collecting in my intake and I do love a clean engine. Inside and out!

You were collecting fuel. Burn fuel more efficiently and you eliminate the reason for collecting it.
Add oil analysis to your belt and suspenders and watch your gas chromatography fuel reading drop and so will your oil colored fuel in the catch can.

customboss · February 2, 2023

9 hours ago, Dr1ft3r said:

Just be careful using a catch can if you live in very cold areas. I've read forum posts about the cans freezing and causing a total block of the system causing engine gaskets to blow out. That pressure has to go somewhere, it will find the weakest link.

My last DI engine was a Lexus RCF and I drove it like I stole it for 80k miles. No catch can and no performance issues at all. I read that regularly changing fuel brands was good for keeping the valves cleaner since different brands use different detergents. So, I usually used a different brand every time I filled the tank. I didn't care about top tier gas and rarely used it. But I did require premium fuel (91+ octane) if that matters.

That's what I'll be doing in this truck too. I don't doubt the science. But I'm regularly in extreme cold during the winter (-20+) and don't want the hassles and potentially huge problems of using a catch can.

Great input!! Water condensate is what can freeze. I am all for capturing that! However no modern IC engine or turbine for that matter will have an unheated scupper or vent system.

customboss · February 2, 2023

10 hours ago, Jettech1 said:

@customboss Have I got a "stupid" story for you. I owned a 2021 Ford Escape SE with the 3 cylinder turbo engine in it that was both port and DI. I installed a catch can on that engine. Talk about stupid right?? Anyhow I use to get an ounce or so every couple thousand miles that I would drain from the catch can. All I was doing was keeping that oil out of the intake. Not overly "stupid" in my opinion but hey, I've done a lot of "stupid" stuff in my days....Made me feel good knowing that oil was not collecting in my intake and I do love a clean engine. Inside and out!

Made me FEEL GOOD. Leave the feelings at the dealership sales pitch and when it comes to automotive science allow data to drive you then you'll do smart things and feel good for a substantive reason. Cheers

C/K Man · February 2, 2023

I wonder how fast the deposits build up when you use E85. There is still a flex-fuel option for the L8T, but it's only available with base trim and certain other options.

Jettech1 · February 3, 2023

11 hours ago, customboss said:

Great input!! Water condensate is what can freeze. I am all for capturing that! However no modern IC engine or turbine for that matter will have an unheated scupper or vent system.

So you know about turbine engines? That's so cool. What is your best turbine engine out there? Mine is the GT90

Jettech1 · February 3, 2023

11 hours ago, customboss said:

Made me FEEL GOOD. Leave the feelings at the dealership sales pitch and when it comes to automotive science allow data to drive you then you'll do smart things and feel good for a substantive reason. Cheers

You crack me up. I love your comments...Please keep them coming....

customboss · February 3, 2023

6 minutes ago, Jettech1 said:

So you know about turbine engines? That's so cool. What is your best turbine engine out there? Mine is the GT90

In 45 years flew, oil analyzed, maintained many turbine engines. jets, helos and even Lycoming/Honeywell M1 army tanks.
GE90 rock solid don’t know a GT90.
At American Airlines we were a RollsRoyce Trent centric outfit. I retired in 2012 from there so not up to speed in the aviation new stuff.
I flew 767-300’s with GE CF6-80 high bypass fan engines.

customboss · February 3, 2023

18 minutes ago, Jettech1 said:

You crack me up. I love your comments...Please keep them coming....

I crack a lot of people up, usually jealous husbands and bar fight opponents......YW

customboss · February 3, 2023

10 hours ago, C/K Man said:

I wonder how fast the deposits build up when you use E85. There is still a flex-fuel option for the L8T, but it's only available with base trim and certain other options.

If your engine is properly tuned IMIO you'll build fewer deposits with higher ethanol content than with current gasoline chemistries with less ethanol. This from testing fuels while at Cummins R&D. We developed a spark E85 engine from one of our turbo 4 cylinder 2.8L compression engines that did great as a delivery van in California. https://www.motortrend.com/how-to/cummins-28l-e85-ethos-project/