Crankcase Vapor Condensor (aka - Sludge Jar)

OK, I finally changed my oil at about 3K+ miles and there was about 1 tablespoon of very dark thick ?oil? in the Crankcase Vapor Condensor jar. The engine oil was definitely dark (black actually) as well but not nearly as dark or as thick as what was in the condensor jar. So it did actually condense at least some of the vapor. And I have now made several improvements since I see that it does work at least somewhat.

Back to the oil change. I added a can of engine flush and followed the directions before draining the old oil and changing the filter. I then added 8 quarts of Shell Rotella and drove the truck for a couple days. Drained this oil hot, replaced filter and refilled with Shell Rotella synthetic and am using a Duramax oil filter (slightly larger - fits well). After a few days of driving the oil is still totally clean.

I have plumbed the CDR directly to the center of the Condensor and added a 1.5" stack of BBs in a 3/4" to 1 1/4" coupling to this intake as well. I stuffed a steel scrub pad into the outlet pipe plumbed directly to the stock adaptor plumbed into the stock intake just before the turbo and just after the air filter.

The extra elbows I had to use for the above connections resulted in a loss of vacuum at idle, remember, it was only 0.5"WC at idle anyway. At idle I now have about 0.5"WC PRESSURE measured at the dip stick. At 1000 RPM, I have about 0.0"WC and at 1500 RPM I have about 0.5"WC vacuum. Now, I will have to observe my oil color and maybe check the condensor jar at about 1000 miles into the oil change. Time will tell all!

Sorry I do not have the final answer yet but this is a try and see type of project. I will keep posting as I have additional info. It will be interesting to see what collects in the sludge jar since I am using fully synthetic oil now. Some of what I have read is that it is the light volatile parts of motor oil that boil off and collect in the sludge jar but, my Ranger below proves there is more that collects in the jar!

Future Improvements:
I may need to add an electric vacuum pump in the future (as suggested in a previous thread) to create enough vacuum at all speeds. Will need to keep the vacuum low though. Or maybe a larger connection to the stock intake ahead of the turbo. The current one is, I believe about 3/8" - a 3/4" would be a 4X increase in the cross section area and flow. Will just have to wait and see.

1992 Ford Ranger 3.0L Gaser with Crankcase Vapor Condensor:
Here is some real good promising news! There is about 4K miles on the current oil and it is only slightly discolored! A dark honey color! And this truck used to have the oil very black by 3K miles! It definitely works on gasers!

Jeg's has this item air/oil separator kit 555-52205 $39.95 small and does the same thing, or?

One of the first things I thought of when I saw the crankcase vent system on the LB7 Duramax was that - this could be adapted to the 6.5. This system uses its own twin PCV valves, condensing chamber, oil return (to the crankcase) hose, and finally a vent to atmosphere.

I like this idea, especially for intercooled 6.5's, as it keeps the oil out of the IC. Oil is a poor conductor of heat.

Jim

Any chance you can show a picture of this setup, or?

I was actually thinking at one time to vent CDV to downpipe on my burb, not sure it's a good idea though.

Pictures are here ("Sludge Jar" thread):
http://www.thedieselpageforums.com/t...ad.php?t=24253
I will try in the next few days to get an updated picture of the outside plumbing as that is what I changed the most.

Don't know about Jegs, will have to research that one. If you have a link please post it.

Screen wire is on top and bottom of the BB stack to prevent any problems. BBs are working very well in the Ranger so, I plan on sticking with them. I believe they are copper coated steel BBs. I think the cylindrical BBs give a greater surface area for condensation. Cylindrical objects are often used for condensation purposes (alcohol stills?!).

I do not want to vent my crankcase to the atmosphere. Engineers got away from this on gasers years ago and boy, was I glad they did! The sludge and moisture build up in engines was terrible - esp. on shorter commutes where the engine does not get hot long enough to evaporate the moisture. And even if it did, I still would not want to open my crankcase to the atmosphere - just asking for more trouble - ash and acid formation, etc.

Good point on the intercooler, esp. on the heat transfer. I do not have one so I am not as keen on that. Someone mentioned the same problem in one of the previous threads. With what I have condensed in about 1500 miles seems it would not take long before the entire inside of an intercooler would be coated and liquid oil pooling in a low spot or being sucked into the turbo. Must have been what the Duramax engineers were concerned about as well!

I am mainly interested in keeping my oil clean so, if this device works on my diesel truck, I will probably modify it again making a horizontal device to lay in front of the CDR. This would most definitely help the low vacuum problem as well.

I will say again, I am very impressed with what this device has done on my Ranger!

Quote:

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Originally Posted by More Power

One of the first things I thought of when I saw the crankcase vent system on the LB7 Duramax was that - this could be adapted to the 6.5. This system uses its own twin PCV valves, condensing chamber, oil return (to the crankcase) hose, and finally a vent to atmosphere.

I like this idea, especially for intercooled 6.5's, as it keeps the oil out of the IC. Oil is a poor conductor of heat.

Jim

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Lot's of oil in my aftercooler.

Jim, do you have any pictures of this duramax pvc setup?

Is plumbing the CDR into my down pipe w/o check valve a good idea? I'm thinking it is but occasional smoke could be an issue, or?

Personally, I would not want to plumb the CDR to the downpipe. Seems like you may have problems creating a vacuum at the turbo exhaust and before the cat (if you have one). You would have to create a venturi effect for sure and I would definitely put a check valve in to eliminate the possibility of blow back. If you have a cat, you may clog or poison it by dumping the crankcase vapor into it. However, if you condense the vapors first then plumb into the downpipe ahead of the cat probably would not harm the cat. Still think you may have some problems creating a vacuum in the downpipe but, then, I am not an injunear.

I do not mean to rain on your parade. It may work great and you may know how to overcome the problems I see. Go for it if you want to try it. I was ridiculed fairly heavy on 2 forums about this idea but, I had read up on it and it was already working on my Ranger.

Nay sayers are everywhere, you did what you though would work and it appears it does, thats good.

I'm not sure how much vacuum if any is needed w/crankcase depression valve it is plummed into the intake of turbo and works like a chimney effect with high pressure air pulling into airstream the vapor from the CDR I'm thinking the high speed exhaust would have same effect but I could be wrong.

Quote:

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Originally Posted by DA BIG ONE

Nay sayers are everywhere, you did what you though would work and it appears it does, thats good.

I'm not sure how much vacuum if any is needed w/crankcase depression valve it is plummed into the intake of turbo and works like a chimney effect with high pressure air pulling into airstream the vapor from the CDR I'm thinking the high speed exhaust would have same effect but I could be wrong.

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It's done in racing applications all the time to create vacuum in the crankcase. But they are open header applications where there is no backpressure. You plumb it right before the header collector. I'm not sure how well it would work on a low RMP truck with a muffler and long tail pipe. Maybe it would, as you are not trying to get too much vacuum anyway. Drag racing engines are trying to get anywhere from 5 to 15 inches of vacuum to help seal the rings and not blow oil out of every gasket. For a free flowing exhaust and one that upsized from the 3" DP to a larger pipe might be able to create some vacuum to pull out vapors if plumbed right before the upsize from 3

Good Day!

"I added a can of engine flush... After a few days of driving the oil is still totally clean." I hate to rain on your parade, but you may have accidentally chosen the wrong time for your experiment. As you're probably aware, we're all being switched from low-sulfur diesel fuel (< 500 ppm) to ultra-low-sulfur (< 15 ppm). In my limited understanding of such, sulfur is the primary culprit that turns our oil black. So, it's just possible that your flush did a good job of cleaning all the black residue out of your engine, & now the ULS fuel AND your condensor are working in combination to not contaminate the oil as much in the 1st place & condensing out some of the crap that turns our oil black. It's too bad your experiment didn't occur long before the switch to ULS, or long after. It has the unfortunate & unavoidable effect of making the results of your work less clear.

Please accept this in the spirit given. I have no doubt that what you're doing has some effect - I certainly don't have anywhere near the knowledge to challenge anything you're doing, & wouldn't if I did. What you're doing in fact sounds like a terrific idea, it's just that the change in fuel occurring right now muddies the waters, so to speak.

Please continue, & let us know how it goes. All the best &...

Blessings!

http://www.thedieselpageforums.com/p...nkcasevent.jpg

The arrow points to the condenser portion of the LB7 Duramax crankcase vent system. The hose on top goes to a valve mechanism on the valve cover, and the two hoses one the bottom - small one drains back to the crankcase, and the other larger one vents to atmosphere.

I've got a better image somewhere.... I'll look.. :)

Jim

moondoggie,

That is a good point about the ULSD - had not thought of that but the state and county I am in does not have the ULSD as yet - some time next year I think. And if the ULSD helps keep the soot/sulfur out of the oil all the better!

At about 1000 miles I will check the Crankcase Condenser Jar and see what is in it and report on that as well. As I said at the beginning of this thread there was some "black syrup" in the jar at oil change. I just walked out to check the color of my oil and it is just as clear/clean as when I put it in 100 miles ago! This is TOTALLY different than what I have been experiencing. The oil used to be black within a few minutes or miles!

I will keep everyone posted. Sorry all of this takes so much time. I am impatient as well and want to know the results now and not have to wait.

Like I said earlier, if this works I have some more improvements in mind. If someone wants to build the improved version I am thinking about post or PM me and I will pass on what I am thinking.

Correct me if I'm wrong...

MP has posted a picture of an oil-air separator. The air goes out the big tube and the oil back to the crankcase via the small tube. Afgunn is proposing exactly the opposite: the condensed vapors are retained in the jar and not sent back to the crankcase (actually, to the intake, IIRC). No?

Yes John... You're correct. The question is, how important is it to separate out the gunk, and not return any of it to the crankcase? I dunno.

A few years ago, some Dodge Cummins owners installed a crankcase vent collection jar arrangement- primarily to help prevent drips on the garage floor. The earlier Dodge Cummins crankcase was vented to atmosphere as well, but without an air-oil separator. I'd bet the TDR has more info on their system at www.turbodieselregister.com

Jim

For clarification:
The Vapor Condenser I built condenses the "heavy" crankcase vapors (fuel blow by?) and allows the rest of the vapors to return to the intake via the turbocharger. From what I have seen and collected, I would not want the condensed vapors to return to my oil (unless filtered very well). I currently have 400 miles on my oil change with an impoved condenser and there is only a slight discoloration to my oil. Previously, it would be quite black by now! At 1000 miles, I will check the oil color and condenser for contents and post.

I want to take task with those who say that what turns our diesel oil black is sulphur. So, what turns a gaser's oil black? That I am aware of, there is little to no sulphur in gasoline. Soot is carbon. Be it diesel soot or gasoline soot, the carbon will turn our oil black.

From what I know, I believe the following:
1) "soot" is the heavier carbon molecules that did not burn during the initial combustion and little or none of it will burn when it is recycled again via a PCV or CDR.
2) I believe most of it is exhausted on the exhaust stroke but some of it ends up in our oil exactly how I am not sure and have not read anything on this either - blow by most likely.

Why do I say the above?
1) Catalytic Converters:
What does the catalytic converter do - diesel or gas? By catalytic action the "material" (noble metal?) in the converter, acting as a catalyst, breaks the unburned heavier (longer chain) carbons (fuel) into smaller molecules and burns them. On later model engines, gas and diesel, extra fuel is dumped to the converter to help it ignite and burn the unburned fuel and polutants.
2) My 92 Ford Ranger gaser with 86K miles, 4K miles on the current oil change and a condenser, has only slightly discolored oil! Never done that before!
3) Engines rebuilt with total seal rings do NOT get black in their oil! Or, at least not as quick or as black.

Quote:

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Originally Posted by afgunn

For clarification:
The Vapor Condenser I built condenses the "heavy" crankcase vapors (fuel blow by?) and allows the rest of the vapors to return to the intake via the turbocharger. From what I have seen and collected, I would not want the condensed vapors to return to my oil (unless filtered very well). I currently have 400 miles on my oil change with an impoved condenser and there is only a slight discoloration to my oil. Previously, it would be quite black by now! At 1000 miles, I will check the oil color and condenser for contents and post.

I want to take task with those who say that what turns our diesel oil black is sulphur. So, what turns a gaser's oil black? That I am aware of, there is little to no sulphur in gasoline. Soot is carbon. Be it diesel soot or gasoline soot, the carbon will turn our oil black.

From what I know, I believe the following:
1) "soot" is the heavier carbon molecules that did not burn during the initial combustion and little or none of it will burn when it is recycled again via a PCV or CDR.
2) I believe most of it is exhausted on the exhaust stroke but some of it ends up in our oil exactly how I am not sure and have not read anything on this either - blow by most likely.

Why do I say the above?
1) Catalytic Converters:
What does the catalytic converter do - diesel or gas? By catalytic action the "material" (noble metal?) in the converter, acting as a catalyst, breaks the unburned heavier (longer chain) carbons (fuel) into smaller molecules and burns them. On later model engines, gas and diesel, extra fuel is dumped to the converter to help it ignite and burn the unburned fuel and polutants.
2) My 92 Ford Ranger gaser with 86K miles, 4K miles on the current oil change and a condenser, has only slightly discolored oil! Never done that before!
3) Engines rebuilt with total seal rings do NOT get black in their oil! Or, at least not as quick or as black.

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Keeping the crud out of crankcase and intake is by far a good idea.

Jim brought up the the lack of heat transfer when aftercooler is oil soaked, big issue for sure, cleaning oil soaked aftercooler is a must.

I examined the duramax setup it is actually like Volvos crankcase oil/vapor separator allowing oil and crud back into engine. CDR system needs this crud catcher too IMHO......

I totally agree!

Something else I learned with the posting and picture that Jim provided. The Duramax crankcase vent system is not using vacuum to draw the vapors out of the crankcase - must only be using the pressure in the crankcase to push the vapors out. I think the CDR system is better, using the intake to create a very small vacuum on the crankcase and draw the vapors out.

Quote:

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Originally Posted by afgunn

I totally agree!

Something else I learned with the posting and picture that Jim provided. The Duramax crankcase vent system is not using vacuum to draw the vapors out of the crankcase - must only be using the pressure in the crankcase to push the vapors out. I think the CDR system is better, using the intake to create a very small vacuum on the crankcase and draw the vapors out.

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I'm thinking a water separator from an air line setup spliced into line form CDR to intake will work just fine. Only issue, how to keep glass bowel on separator protected?

I have my CDR plumbed staight out the bottom of truck with a hose and have noticed since I did that the intake inside is now nice and clean and has been that way since I switch and cleaned it out.

Big One,
I do not know if the water separator would work. From my experience the vapors need to pass through something (BBs) in order to cool and condense. I had only a steel scouring pad earlier and it worked some but not as good as the BBs. But if you want to give it a try, go for it. I can definitely be proven wrong! The glass can be protected by putting it in a larger can (coffee can, large bean can) and wedging in some rubber hose.

Marktara,
Venting to the atmosphere would concern me as the engine can draw in moisture after the engine is turned off and as it cools down. I think this is one reason OEMs got away from the old "oil breathers" from "yester years". Seems like the tube would drip oil as well. Good info on how the intake is staying clean though!

Don't Mercedes Benz use a similar system on their trucks?

Good Day!

What's the latest, afgunn?

Blessings!

has anyone tried to measure crankcase pressure at WOT with the higher boost pressures that most of us are running. I'm thinking no matter how good the rings are sealing there is at least 3% blow by on a good day. Now double the factory boost from 7 psi to maybe 15 psi, is the factory CDR just too small? in the factory service manual there is a note state the CDR was designed to handle 4 cfm of blow by. a 6.5 at 15 psi boost and 3% blow by at 3600 rpms is just over 15 cfm, thats almost 4 times! maybe a combination of the CDR and the addition of a downdraft tube in the down pipe is needed.


95 C3500HD , 96 C3500HD, 95 C7500 Cat