Whats up guys,

I know this topic has been covered a million times, but I'm just looking for a little clarity as to what is going on with my specific situation.

2008 6.4 161k miles, fully deleted at 160k.

Decided to do the CCV mod, bought the kit through SPELAB and threw it on the truck. I plugged the hole on the intake elbow and ran the hose down the passenger side wheel well and sent it. Immediately noticed a bit of white smoke, not a ton but a good enough amount to get some interesting looks from other drivers when stopped at a red light. The smoke comes out in a light but consistent stream, no signs of coolant but it is definitely accompanied by some "oil mist". I understand that there is great debate over blow by on these engines and what is considered normal.

Trying to solve the problem, I installed an oil catch can, sealed with no breather filter installed. CCV hose to the inlet of the can and a hose from the outlet to the exhaust. After a bit of the drive I took a look and noticed oil had made it through the can and traveled 4-5 feet of hose and into my tail pipe. The can itself was practically empty.

After that fun I installed the breather filter on the can and ran the truck only to find oil making its way out through the breather this time. Also wanted to note there is a good amount of pressure in the can. When i open the drain valve with the engine running, I get a pretty good woosh of pressure.

It's by no means dumping but seeing that it made it back to the exhaust was bit concerning.

How much oil am I supposed to be seeing here?
Should I be routing the hose with an initial up hill to keep oil from escaping at the engine?

If you made it this far I appreciate you and any feedback. This has got me scratching my head and feeling nervous.

 

What size hose are you using to plumb this CCV system? I'm guessing its pretty small ID hose. Basic hydraulic principle, as ID size of the hose goes down, velocity of the gas inside goes up for the same flowrate.
And if you have pressure buildup that's a bad thing. That pressure in the crankcase is also trying to push out every oil seal and will likely result in your engine becoming a oil fountain.

If you want to run a CCV system with a catch can, make sure if can handle the high blowby flowrate of the 6.4 and plumb it using hose that's at least 1 inch in size. In the way, way back days I had to make my own catch can CCV system for the 6.4 because there wasn't one available that would work, but that was decades ago now (back when the 6.4's were still new), so perhaps something off-the-shelf exists now.
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First off, I just saw that I posted this in the wrong section. New here and jumped the gun, was unaware of the designated 08 - 2010 6.4 section of the forums. Maybe this post can get moved over there?

@Antonm23 that makes sense, the kit from SPELAB came with what looks like 3/4'' ID hose. The catch can I bought was a cheapo amazon find. It has all the baffling and filtration inside it. Between that and the maybe 1/2 hose barbs on the inlet/ outlet it's probably creating a huge bottle neck. Does that make sense to you?

I'm a welder by trade, I got some 4'' stainless pipe laying around the garage that I think would work well as the body of a new can. Might as well fab up my own larger, wider can with more capacity and flow. Would be a whole lot easier to keep everything at 3/4'' ID with what i have on hand. You think that would suffice or is 1'' really the smallest diameter I can get away with?

Thanks for chiming in!

 

IDK about the 3/4 hose really. I initially put a cheesy little catch can on mine and it ended up pressurizing the crankcase so much that the turbos couldn't drain their oil and oil came out the exhaust. After removing both turbos (cab on in my driveway, which was no fun) and rebuilding the them, I made my own catch can and used 1" line & fittings everywhere. That setup worked for the next 10 years or so until I sold that truck.

Sorry no pictures of the homemade CCV system on this computer (it was a long time and a few laptop PC's ago now). Since that truck was EGR deleted as well, I mounted the catch can where the vertical EGR cooler had been and put a ball valve on the bottom so I could drain it. It was a closed loop design in that gases ran from the passenger side valve cover, through the catch can/ oil separator and back to the intake tube. I worked pretty well, under daily driving it caught some oil, but when towing heavy (I had a 43 foot fifth wheel toy hauler camper at the time), it would catch/ separate a lot of oil from the blowby gasses (after about a thousand miles of towing the trailer I'd drain about a quart of oil out of the separator can). This was all when the 6.4's where still relatively new and the truck had 40K miles on it (right after the warranty expired the deletes and CCV system went on).
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Yea I think that was the problem, I was just "bottle necking" the **** out of it. Do these engines just have a ton of blow by? A quart down on oil is kind of a lot, no? no doubt that's a big trailer but jeez....The mod kit came with 3/4, so I mean someone had to think about that right? lol The can I started on last night has a little over a 1.5 - quart capacity if my math is correct. It's going to offer a heck of a lot more flow than the previous can. I can order some 1'' stuff...

The bigger question now is do I route it to atmosphere or back up to the intake... hmmmmm?

 

Yeah the 6.4 has a lot of blowby even when new.
It was done that way on purpose to allow for extended high EGT's (like seen when towing heavy loads uphill) without the ring gaps butting. So the CCV system needs to be able to flow a lot of CFM.

I took my CCV back to the intake, but there is no issue with just venting to atmosphere other than smell. Since when I did this the truck was still pretty new (and it was an expensive King Ranch Dually), and I didn't want the smell, so I made it go back to the intake. I thought about using some crankcase evacs like old drag cars had in the header collectors ( see link below to what I'm talking about), and letting it go out the exhaust system. This could potentially work, but the crankcase would have to build enough pressure to open the check valves, so there would always have to be at least some positive pressure in the crankcase. With it going back to the intake the highest pressure it should ever see is atmospheric pressure, usually a negative pressure, never any positive pressure.

https://www.summitracing.com/parts/s...SABEgKfO_D_BwE
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I got you. Thats crazy, didn't even know that was a thing. I assumed any blow by was always a bad thing! The YouTube link is a short clip of the truck running. Like I said, its consistent but it's not a ridiculous amount of smoke. Just enough to be noticeable. I'm actually glad I did the reroute, I don't want all that crap going back into the engine. I know it's probably not the worst thing, but it certainly can't be the best.

This look about right to you? ^^^^