I’m with Luke. The room under the hood is awesome compared to my 02 even if I yank the twins and dual fueler. Lots of parts come off in big chunks
Venturi catch can setup
- Thread starter Chevy1925
- Start date
Pcv re-route done. Super simple.
No need for a bored out horn imho. It’s literally the same size at the turbo bore with a slight lip for the surge port to recycle back.
Tube coming off. I hate these one time use pos bands
She’s a 7/8” dia. Rubber cap from autozone and good to go with a hose clamp
Turned around and popped the hose over the intercooler tube, added a 7/8 barb I found at ace hardware and some 7/8 oil line I had from another project
Now there is a metal tube coming from the outlet side of the turbo that goes down into the factory catch can. No idea what it does. Might have to look into that. You can see the tube in the pic with the intercooler tube and the pcv hose going over it
No need for a bored out horn imho. It’s literally the same size at the turbo bore with a slight lip for the surge port to recycle back.
Tube coming off. I hate these one time use pos bands
She’s a 7/8” dia. Rubber cap from autozone and good to go with a hose clamp
Turned around and popped the hose over the intercooler tube, added a 7/8 barb I found at ace hardware and some 7/8 oil line I had from another project
Now there is a metal tube coming from the outlet side of the turbo that goes down into the factory catch can. No idea what it does. Might have to look into that. You can see the tube in the pic with the intercooler tube and the pcv hose going over it
Found this on Mitchell. Their wording makes it a little hard to follow, but it sounds pretty similar to the LML PCV system.
An oil/air separator (2) is located on the left valve cover. Oil entrained gases from the crankcase enter the separator through a passage in the left valve cover. The gases flow through fixed and variable nozzles inside the separator which aid in removing oil from the gases. The nozzle varies flow based on the turbocharger compression vacuum to control crank case pressure. Fine oil particles coexsit on a synthetic flog impactor and drop into the sump. An eductor, fed by the turbocharger feed line, operates under the venturi principle and forces oil to drain into the left rocker cover.
Oil removed from the crankcase gases at the separator pass through tubing (4) and down to a check valve (5) at the bottom of the engine front cover (6). The oil drain check valve prevents the back-flow of crankcase pressure upwards through the drain. It allows oil to flow back to the crankcase when drain column pressures are above 2 kPa (0.29 psi).
Crankcase pressures are maintained between approximately -2.5 and +4 kPa (- 0.36 and 0.58 psi) during all engine operation modes.
With a closed crankcase ventilation system, it is normal for oil residue to be found on the turbocharger compressor wheel and inside the charge air cooler, pipes, and hoses.
No routine maintenance is required to the crankcase ventilation system.
Here's my take on the line from the compressor outlet:
In both the old and new PCV setups, the intake is used to create a pressure differential (less pressure in the vent line than in the crankcase) at the vent port on the valve cover. The previous motors (and most other factory turbo PCV systems) directly used intake vacuum from the pre-compressor portion of the intake to draw air out of the case. With this new setup the vacuum is created by a venturi inside the separator. In order to create a venturi though, steady airflow is needed. Under boost, pressurized air from the compressor outlet flows through the separator back to the compressor inlet. Inside the separator, air from the crankcase is drawn into the main air stream where it is forced to flow across a "synthetic flog impactor" to separate the oil before it's carried back to the compressor inlet. Same principle that most sandblasters and paint guns operate on, only here we're moving crankcase air/oil vapor instead of sand and paint.
Non boost operation (idling/decel/etc.) is where my interpretation of Mitchell's description gets a little cloudy though. Is there enough of a pressure differential from the compressor inlet to outlet to provide adequate flow to create a venturi? Or does it function like the old system, since both the compressor inlet and outlet are under relatively low pressure compared to the crankcase?
Also, if this is how the L5P PCV functions, wouldn't crankcase ventilation be superior in the factory configuration with a catch can between the separator and the compressor inlet? That way the crankcase air is being evacuated by intake vacuum rather than having to push it's way out of an atmospheric vent? I'd be curious to see how big of a difference, if any, there is in crankcase pressure between the two. Not trying to question your method James, I've got the exact same vent scheme on my LMM, and I've read enough of your posts to know that you've got far more experience with these trucks than I do!
I'm not 100% sure this is how the new PCV operates, I'm just using what I know to connect some dots. The last thing I wanna do is spread misinformation, so if I'm way off someone please correct me, I promise I won't get butthurt :thumb::thumb:
An oil/air separator (2) is located on the left valve cover. Oil entrained gases from the crankcase enter the separator through a passage in the left valve cover. The gases flow through fixed and variable nozzles inside the separator which aid in removing oil from the gases. The nozzle varies flow based on the turbocharger compression vacuum to control crank case pressure. Fine oil particles coexsit on a synthetic flog impactor and drop into the sump. An eductor, fed by the turbocharger feed line, operates under the venturi principle and forces oil to drain into the left rocker cover.
Oil removed from the crankcase gases at the separator pass through tubing (4) and down to a check valve (5) at the bottom of the engine front cover (6). The oil drain check valve prevents the back-flow of crankcase pressure upwards through the drain. It allows oil to flow back to the crankcase when drain column pressures are above 2 kPa (0.29 psi).
Crankcase pressures are maintained between approximately -2.5 and +4 kPa (- 0.36 and 0.58 psi) during all engine operation modes.
With a closed crankcase ventilation system, it is normal for oil residue to be found on the turbocharger compressor wheel and inside the charge air cooler, pipes, and hoses.
No routine maintenance is required to the crankcase ventilation system.
Here's my take on the line from the compressor outlet:
In both the old and new PCV setups, the intake is used to create a pressure differential (less pressure in the vent line than in the crankcase) at the vent port on the valve cover. The previous motors (and most other factory turbo PCV systems) directly used intake vacuum from the pre-compressor portion of the intake to draw air out of the case. With this new setup the vacuum is created by a venturi inside the separator. In order to create a venturi though, steady airflow is needed. Under boost, pressurized air from the compressor outlet flows through the separator back to the compressor inlet. Inside the separator, air from the crankcase is drawn into the main air stream where it is forced to flow across a "synthetic flog impactor" to separate the oil before it's carried back to the compressor inlet. Same principle that most sandblasters and paint guns operate on, only here we're moving crankcase air/oil vapor instead of sand and paint.
Non boost operation (idling/decel/etc.) is where my interpretation of Mitchell's description gets a little cloudy though. Is there enough of a pressure differential from the compressor inlet to outlet to provide adequate flow to create a venturi? Or does it function like the old system, since both the compressor inlet and outlet are under relatively low pressure compared to the crankcase?
Also, if this is how the L5P PCV functions, wouldn't crankcase ventilation be superior in the factory configuration with a catch can between the separator and the compressor inlet? That way the crankcase air is being evacuated by intake vacuum rather than having to push it's way out of an atmospheric vent? I'd be curious to see how big of a difference, if any, there is in crankcase pressure between the two. Not trying to question your method James, I've got the exact same vent scheme on my LMM, and I've read enough of your posts to know that you've got far more experience with these trucks than I do!
I'm not 100% sure this is how the new PCV operates, I'm just using what I know to connect some dots. The last thing I wanna do is spread misinformation, so if I'm way off someone please correct me, I promise I won't get butthurt :thumb::thumb:
Like Tim said, that’s pretty much it. Under the low boost or no boost, your not making much crankcase pressure so what does come out would be like the old factory systems, assuming much even does come out.
Additional catch cans still won’t catch everything beyond what the stock setup will. Better but you will still get oil vapor ingested over time. I just prefer to vent to atmosphere at this point. Simple, easy, and has caused no issues
Additional catch cans still won’t catch everything beyond what the stock setup will. Better but you will still get oil vapor ingested over time. I just prefer to vent to atmosphere at this point. Simple, easy, and has caused no issues
I’m a noob when it comes to this stuff, but what are you gaining by doing this? Just a little less hot air to the turbo? Is there other ways for the crank to vent? Is it making for a healthier motor? I’m working on getting someone to help with some parts falling off, but for now I’m willing to do anything that will help! I’ve installed a bypass filter system and if venting that house down along the frame helps, I’m all in. Is there any chance it could pull sand or water into the turbo in off road conditions? Thanks and sorry, but I’m trying to learn as much as I can!! I truly value the combined knowledge in these forums!
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The oil mixed with the EGR makes for a mess in the intake. I prefer to block the egr as the oil doesn’t bother me
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But in this case the OP is blocking the chance for any oil, correct?
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I would rather ditch the egr or block it as well but this also stops build up of crap in the turbo and after as noted by the pics of other members.
Little update, 4k on the reroute and took it out to check and clean the tube.
there is a decent amount of oil on the barb and in the hose. You can also see quite a haze come out under the truck when it’s venting at idle. All that crap would have been in the turbo as this point
there is a decent amount of oil on the barb and in the hose. You can also see quite a haze come out under the truck when it’s venting at idle. All that crap would have been in the turbo as this point
Looks the exact same. Going to do some stuff with the kids this morning, then I’ll see about pulling the intake horn as well and rerouting the pcv. Might be able to do my own bigger horn mod like my lb7 one I did.
I'd advise against modding the intake mouthpiece.... It will create a turbo surge. I can promise you that. It relies heavily on the mouthpiece flow dynamics to keep the turbo out of surge.
Little update, 4k on the reroute and took it out to check and clean the tube.
there is a decent amount of oil on the barb and in the hose. You can also see quite a haze come out under the truck when it’s venting at idle. All that crap would have been in the turbo as this point
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Meh... If I remember correctly, I think it pulls pressure from the outlet of the turbo to feed into the pcv system for the vapor control. Open part of it to atmosphere and it breaks the system. The 17 I had, had very little oil residue on the intake at 50k miles.
gotta keep reading joshy
, later i wrote how there is no point in it as its very fluid into the turbos intake sideThe pressure side is still there, this is strictly the large tube side that sees vac or no vac based on the turbo drawing air in. it should have no affect on how it works, just where the end result ends up.
yup! went back to stock a couple months ago when i needed some warranty work, then changed it back. No issues since. i do need to add a venturi to the exhaust either pre or post dpf. while its not going to have the flow to draw a significant vacuum on it, im more wanting it there to lessen the smell of the oil vapors and carry it out the back.
I’d honestly be curious. Might need to hook a back pressure gauge up. It can’t be that restrictive, specially with a turbo that is mapped very well for the power it puts out
i wonder if there is a pressure differential PID or way to monitor pressure already. ill have to play with my mdi when i get time.