CCV or How much oil is normal going thru the turbo

Steve777 · **Joined:** Fri Oct 16, 2015 11:31 pm **Posts:** 279

I've read some of the other threads on the CCV and the one on Provents and EHMs, but I am still concerned that too much oil is going into the air in the intake on one of my CRDs. Here's my story:

So I did some standard maint stuff (changed oil & filter, air filter, etc) and while I was at it pulled the hose to the turbo and check it for play. Turbo shaft was perfect, no discernible play in any axis. Put things back together and did not finish tightening the clamps on the turbo to intercooler air hose, was going to look up the torques. Anyway spaced out that final tightening (my BAD). Took the CRD on my usual 2 mile test loop around my place, and the hose at the turbo popped. Knew what happened immediately, from the pop to then remembering my never finishing the tightening. Was maybe 1/2 mile from home so I just drove there, slowly and with a fair amount of black smoke.

As expected there was a bunch of engine oil spray on the exhaust side of the engine from the loose turbo hose. Maybe a 1/2 teaspoon of it on the top of the turbo actuator and all over the hoses and heat shield around there. Not that hard to clean up but it has me a bit concerned, should 1/2 mile of that hose being off really have sprayed out that much oil? It seems like a lot of oil. (BTW an ERG block off plate is in place) Even when the hose stays in place, all that oil is going thru the cyls and out the exhaust not back into the oil pan. Seems like an awful lot of lost oil in just 1/2 mile of driving... Just some rough "back of the napkin" calcs here: 1/2 teaspoon per 1/2 mile means 1oz of oil every 6 miles, means 1 qt of oil every 200 miles (roughly), which is high oil usage. Unless of course the hose being off upset the vacuum balance and itself causes more oil to come out the CCV.

When I had the airbox to turbo inlet hose off, one could see an oil slick from where the CCV hose comes in, so that seems to be the likely source of this oil.

So my questions are:

1. Is this amount of oil "normal" to be going thru the intake air?

2. How does one test the CCV? Just replace it when too much oil is being circulated? [I am aware of the Provent, but think I need to figure out if the CCV is acting normal or needs replacing first].

Thoughts, tests I can do?

TKB4 · **Posted:** Sat Aug 31, 2019 11:41 pm

I believe there is not only a fairly large margin of error with such a small sample size but I also believe a significant amount of that oil was likely coating the inside of the hose etc and wasn't necessarily circulating oil at that rate. I have no idea exactly what the normal is but I think it is quite a bit judging from seeing what comes out of EHM and oil fill tube with engine running . apparently a lot stays aerosolized and eventually drains back to crankcase via intake/head. I am actually surprised that people report removing only a few ounces recaptured from their prevent after several thousand miles.

I don't know a particular way to test the CCV other than it allows air to escape or it doesn't, but it can be cleaned.

Unless oil consumption increases significantly, since you have blocked the EGR I wouldn't worry about it , but I do have curiosity.

flash7210 · **Posted:** Sun Sep 01, 2019 7:31 am

I think its impossible to know how much CCV oil is normal.
Lets just consider all CRD engines to be abnormal in this aspect.

The Provent traps most but not all the oil coming out of the CCV.

mrhemi · **Joined:** Tue Dec 08, 2015 10:46 am **Posts:** 180

Underneath the CCV, in the cam/intake casting, there is a drain back hole to empty what is collected in the CCV. This drain back is prone to clogging as it is actually a loop seal. It needs to be cleaned every oil change to prevent build up. I usually run a pipe cleaner through it. There is an obscure mention of this in the FSM. It has also been discussed in a previous thread or two. I have two CRD's, neither of which blows excessive oil into the turbo inlet. When initially acquired, both of these vehicles had plugged drain back hole and blew excessive oil into the turbo. The CCV is actually a cyclonic separator of a sort, but needs to be able to drain what it separates or it fills up and goes into the turbo.

Steve777 · **Joined:** Fri Oct 16, 2015 11:31 pm **Posts:** 279

Thanks mrhemi. It would seem that my CCV is clogged or broken.

I'll look in the FSM, but is it easy to describe where this drainback hole that needs cleaning is located? I assume it is the small hole (~1/4") in the center of the front attachment to the cam cover, the one with the spirals in the plastic around it. If so that was clean on my CCV, but I could try probing around in there maybe it is junked up somewhere I can't see it. Otherwise sounds like time for a new CCV.

WWDiesel · **Posted:** Sun Sep 01, 2019 2:59 pm

mrhemi is dead right! You can pull the CCV puck and check the drain back hole underneath it. There is also a "J" trap under the drain hole that can become clogged, it must be cleaned out with a pipe cleaner or similar device. I will post pictures of when I did mine.

Next, add a ProVent 200 filter, it is a "Coalescing Cyclonic" type filter by design. It separates the 'phases' of any water and / or oil aerosols and any liquid droplets from the gaseous vapors leaving the CCV that is being sucked into the turbo inlet. A coalescing type filter element is installed inside the ProVent housing. The housing has three ports; the incoming wet or vaporous laden gases have to pass through the top of housing in a cyclonic circular direction which allows the heavier droplets to fall out of suspension and drain before the gasses enter the filter element where they are collected on the filter material and allowed to drain to the bottom of the filter housing where they are collected and can be drained off at maintenance intervals. The filter housing also contains a "Safety Valve" to prevent any pressure from building up in the CCV system in case there was any kind of stoppage.

Lots and lots of good reading on this subject on LOST, here are a few:
viewtopic.php?p=927939#p927939
viewtopic.php?f=5&t=80491
viewtopic.php?p=848327&sid=11b0e2dd28ee12029f29df1c91dc9603#p848327

Picture of drain hole in top of valve cover under CCV Puck.

Picture of "J" trap under drain hole in valve cover:

iakj11 · **Posted:** Mon Sep 02, 2019 9:37 am

If a pipe cleaner can't be found, flexible plastic string trimmer line works well too.

Seeing those pictures again makes me wonder if that J shaped hose could be modified in any way to allow more effective draining. May be a delicate thing, with all of the dynamics of the moving air and oil and all...

TKB4 · **Posted:** Mon Sep 02, 2019 10:11 pm

that is what I meant by cleaning
the CCV other than it allows air to escape or it doesn't, but it can be cleaned.

mrhemi · **Joined:** Tue Dec 08, 2015 10:46 am **Posts:** 180

The J shaped tube cannot be modified. It is actually a "loop seal" the design keeps a constant head of liquid oil in it to prevent the vacuum of the turbo inlet draw directly on the crankcase (there by drawing in more oil directly). However it allows the accumulated oil to gravity drain back into the engine. Google "Loop seal" for a better explanation.

Steve777 · **Joined:** Fri Oct 16, 2015 11:31 pm **Posts:** 279

Thanks all. One question on cleaning this J tube and drain, is the pipe cleaner shown going in the top of the valve cover in WW's pics the some one as is coming out the J tube on the bottom? Or was that two different ones doing the cleaning?

Just curious, since I did not think to clean that J tube when I had the intake off, I am wondering if I can get it now from the top.

WWDiesel · **Posted:** Thu Sep 05, 2019 1:21 pm

Steve777 wrote:

Thanks all. One question on cleaning this J tube and drain, is the pipe cleaner shown going in the top of the valve cover in WW's pics the some one as is coming out the J tube on the bottom? Or was that two different ones doing the cleaning?
Just curious, since I did not think to clean that J tube when I had the intake off, I am wondering if I can get it now from the top.

Yes, it can be cleaned from the top with the CCV Puck removed!

The first picture is looking from the top with the intake/valve cover installed and the the CCV Puck removed to clean out the "J" tube from the top.
To clean; spray it out with a little penetrating oil or a very small amount of spray brake cleaner or push a pipe cleaner soaked in cleaner through it to clean.
Just remember, whatever you spray into the top of the "J" tube is going into the engine to mix with the oil.
I did mine just before draining the engine oil for an oil change.
I also dissembled the CCV Puck and cleaned it out good while I had it off the engine.
Link to pictures of dissembled CCV Puck:> viewtopic.php?p=927939#p927939

The second picture is showing the "J" tube in it's entirety as viewed from the inside (under side) of the valve cover (intake/valve cover off) so people could see exactly what the "J" tube looks like. :mrgreen:

TKB4 · **Posted:** Thu Sep 05, 2019 2:27 pm

The J tube basically serves a similar purpose as a P trap on HVAC units or similar to an S trap plumbing drain.

GordnadoCRD · **Posted:** Thu Sep 05, 2019 6:53 pm

TKB4 wrote:

The J tube basically serves a similar purpose as a P trap on HVAC units or similar to an S trap plumbing drain.

Thanks for clarifying that. I always thought the pee trap was for urinals.

iakj11 · **Posted:** Thu Sep 05, 2019 8:26 pm

mrhemi wrote:

The J shaped tube cannot be modified. It is actually a "loop seal" the design keeps a constant head of liquid oil in it to prevent the vacuum of the turbo inlet draw directly on the crankcase (there by drawing in more oil directly). However it allows the accumulated oil to gravity drain back into the engine. Google "Loop seal" for a better explanation.

Makes sense. Thanks!

Steve777 · **Joined:** Fri Oct 16, 2015 11:31 pm **Posts:** 279

Ok did some more digging, but am still puzzled...

With all the tubes and flanges cleaned up and clamps properly tightened, intercooler tubing does stay put

.

I did run a wire tie thru the J tube port and took apart and cleaned the CCV. Both seemed pretty clean from the start so I don't think that was the problem, but they are definitely clean now.

I have to change my comments on turbo shaft play. I did a test while it was still hot/warm and could detect some play that I did not feel before. Have not measured with any tools, but "guessing" from moving things with my fingers, feels like 1/16" in-out play on the shaft, maybe a touch more. Very little, maybe .005" up-down and left right. And when I went back after it had cooled, I could feel that play then too, but had to push it a bit to get it "loose". I don't know if that is enough to start worrying about the turbo, anyone here have any guidelines. When I checked the forums here, there is a wide range of answers on this; anyone know what the good/bad cutoff points are for turbo play??? From my experience with TDIs that much turbo play isn't too bad, but I wonder if it could be causing all this oil in the intake?

There definitely is an oil leak, comes down the left side of the engine in back, runs along the case behind the starter. The wires above this are getting oil soaked too. But the rubber coolant hose a bit higher to the EGR seem clean. Intake bolts on that side are tight (at least all the ones I could reach with the common rail installed), and I don't see any oil traces from that high (although it's a bit hard to see in back). There have been drops of oil collecting on the bottom of the FCV. And after cleaning everything up, and going 5 miles for a test drive, when I pull the intercooler to FCV hose at the FCV, there is a bit of engine oil in there on the FCV flange and a bit more in the hose (like 1 teaspoon). So it seems likely that oil coming thru the intake is the source although could be two problems I guess).

So I am not real clear where to keep looking at for this leak. I suppose I could clean things up again, do a temporary EHM so that no CCV oil is getting into the intake, and see if I find oil again in the FCV after a few test miles. Then it would have to be turbo or in the intercooler. And I suppose I could also pull the intercooler and see how much oil has collected in there (it's 10k miles old).

One other maybe complicating factor. I put in a WW style block off plate while doing the other work (thanks WW). The car supposedly has a EGR delete tune, but I am pretty sure it isn't working, cause the oil gets black very fast and when I pull the MAF plug it throws a P0102 code, which was supposed to be blocked. Anyhow I put that plate in there to help reduce carbon. But I got to wondering, with no air/exhaust flowing thru that pipe when the FCV closes, could that be allowing intake oil to run down and collect in that tube (it is a low spot), and maybe leak out if a lot is just sitting there? (and perhaps even spike the boost pressure if the FCV is blocking the intake) I know the FCV is working cause I hear it release just after I turn the engine off, so I assume it is closing at other times too (thus the pulling of the MAF plug and P0102). Just curious what happens when one puts in a block off plate but the tune you have is still trying to work the FCV. Anyone know how this works or doesn't? I do plan on getting a GDE eco tune, but was waiting until all the other issues were "fixed" (haha).

Any other engine oil leak sources on the left rear side of the engine that would leak down behind the starter and wet the wires in that area?

Thoughts, suggested test?

TIA

TKB4 · **Posted:** Mon Sep 09, 2019 8:57 pm

If you are worried about oil coming from the FVC to disabled EGR go ahead and remove the butterfly and block off the FVC to EGR tube with or without modifying the pipe like this and some permeated or like WW says use a knockout "coin" from electrical box etc.
https://imgur.com/d5Y8SO1

See this post
viewtopic.php?f=5&t=90293

For your approach to mean anything you would have to remove the intercooler and wash it out since there is likely quite a bit of oil in it that will continue to make its way to the FVC whether or not you have a temporary Elephant hose and whether or not the turbo is currently leaking oil.

The bigger question to me is where is the oil getting out of the closed system. Maybe rear main seal somewhere or cracked block etc ?

GordnadoCRD · **Posted:** Mon Sep 09, 2019 9:34 pm

could also be a split or compromised intake camifold gasket.

These are good gaskets to the point of being usually re-useable, but a failed one could pose a very hard-to-find oil leak situation.

Steve777 · **Joined:** Fri Oct 16, 2015 11:31 pm **Posts:** 279

Thanks Gordnado, thought of that. That's why I did check the bolts I could reach to see if any were loose, but of course the gasket can fail even without loose bolts. Did use a new gasket.

I need to get out my inspection mirror set and take a closer look back there. From what I could easily see, the area directly under the intake/head seam looked dry. But with the intake protruding out I could have missed something.

WWDiesel · **Posted:** Mon Sep 09, 2019 11:12 pm

You may want to consider putting some UV dye in the oil and use a UV light to help pinpoint the root source of the oil leak.
https://www.autozone.com/test-scan-and- ... 835775_0_0

Steve777 · **Joined:** Fri Oct 16, 2015 11:31 pm **Posts:** 279

TKB4, thanks for the pics, looks like a good way to disable things.

And that is the question which has been puzzling me, where is the oil coming from? If not the CCV/turbo then where? I suppose it might be a rear main, but when I clean things up under there and then go for a drive, it is the left rear side of the engine which gets wet with oil first, not the back of the oil pan or between the engine and tranny which is what I would expect if the rear main was the source. Also a rear main leak would not put oil in the FCV. A leak up top at the head gasket or intake gasket could be the source, although unless the oil is running around a corner before going down on the block, there isn't a trail to point this way. And again these sources would not explain the FCV oil.

My theory (guess) was that it is turbo/ccv oil as the main maybe only source. And that it is collecting in the intake tubes and FCV area and then leaking from there. placement is about right for that. I know all those tubes and pipes are supposed to be sealed but... (and I did check and things are tight on those connections) It seems that the FCV to ERG tube would be a prime low place that might fill with oil, given that it is on the bottom of the FCV and turns down. A bit of a pain to remove, so I haven't done that yet but probably will if I haven't found the source soon. And even if it is full of oil, still leaves the question of how is that oil getting into the intake.

Also your point TKB4 on the intercooler needing cleaning (which again is a bit of a pain to do) to really tell much back at the FCV is a good one. Though I think if I did an EHM and cleaned the inside of the turbo to intercooler tube before the test, the presence or absence of oil inside that rubber hose (as well as seeing what's coming out of the EHM) should give some idea of if the ccv and/or turbo are sending oil out.

Still trying to get a definitive answer to how much turbo shaft play is acceptable, in terms of when it starts leaking oil. Decided to call a few turbo rebuilding shops and ask them details on costs for their services and how I can tell if my turbo needs rebuilding in their opinion. Got the same range of answers from them as there is on the forum here (and elsewhere online). Some say any along the axis shaft play is bad. Others say it doesn't matter much as long as it is not excessive and no contact. Be nice to hear from someone who knows for sure, or who has both a new and old turbo sitting on the bench and can compare. Anyone?

One other possibility that one of the turbo places suggested, it could be a clogged oil return pipe. He said if the return oil flow is stopped (clogged line or high pressure in the crankcase) then that oil in the turbo will find its way out the turbo seals. No reason to think that line was clogged but could be. Again an awful lot of work to check something that seems pretty unlikely. EHM test would likely eliminate the high crankcase pressure issue.

Open to other tests or suggestions...

CCV or How much oil is normal going thru the turbo

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