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Engine Specific Info and Questions => IDI Engine => Topic started by: Gizmoman on September 28, 2013, 08:48:31 am
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Not to hack another's post "blue smoke" I figured I'd start another. . .
Getting close to running after a year of diddling, I am concerned about getting oil into my intake.
Here is a shot of my k14 drain line
(https://lh6.googleusercontent.com/-VB5Y3W1QPCk/UkbzWiS29vI/AAAAAAAACGc/8s59B7bUNDg/w869-h652-no/DSC00641.JPG)
Here is a screenshot of the WAIC intake manifold with two laminova cores inside. I really don't want any oil clogging up the tiny fins.
(the divider plates between the core housings are not shown here, but they are there in the real part. The intake air must flow through/over the cores).
(https://lh4.googleusercontent.com/-XmPIbSvYDKo/USTzjsZTFCI/AAAAAAAABfA/-SnVeqqJ8_A/w927-h652-no/Laminova+WAICAAZ.JPG)
(https://lh3.googleusercontent.com/-lnY4FsqCCAU/Uan70oIUSPI/AAAAAAAACE8/a_YoMRXXcYM/w869-h652-no/DSC00476.JPG)
I plan on running the blow-by into a can and then drain back into the block - maybe a "T" fitting on the drain line or I'll use the original drain port which I have plugged at the moment. A bigger concern is the oil from the turbo as I know the seals are really just slingers and not 100% "seals".
I'd like to hear opinions on the best way to insure no oil gets into the intake. If I did this again, I'd of made the manifold with a removable cover so I could get the cores out easily and clean them if needed. As it is, they are going to be impossible to remove without taking off the manifold.
(https://lh5.googleusercontent.com/-YJsH1_XC8dU/Ukb5E__I3xI/AAAAAAAACHs/SNXJf6lx6h8/w869-h652-no/DSC00650.JPG)
Any ideas?
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There are only two things that come to mind from looking at the first pic. Install a clamp type bracket around the stainless line to secure it to the bracket going to the engine.
Second, I am assuming that the blue line is coolant and is a push on type hose and barb. But the black lines are not. So where are the hose clamps on that setup? This system is under how many psi on the coolant lines?
Just my coffee quick obs for the morning. sip.
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ORCoaster, you are correct, the blue and black hoses are coolant lines for the WAIC. All the fittings are push-on and so are the hoses. Trust me, once I pushed them on (really tough to do), they are not coming off without a knife. The pump is rated at 25 PSI and there are no valves in the system. I also have an overflow tank hooked up to a 2-1/2 gallon tank I made from 4" PVC for the main supply. In other words, not enough pressure to even consider.
Maybe that oil drain line looks long and heavy from the camera angle but it's really only about 18" and the #8 Jic fittings are rigid so there's nowhere for the hose to flop about (if that's your concern).
What is your perspective on the oil drain line emptying below the oil level?
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imo your drain just fine.. still at highest point in the pan... my bae kit, that laked instructions in june 96 when i got it had a pan with a barb down by the drain plug.. i insstalled it turkey day 96 and redid the pan as i either read or was told the pan that came with it would never work.. and in 00-01 when i got the instruction book fo ra bae kit.. i think it had a note with th e"where to put return line" stating bad things... and it showed to do it how i did it when i built it in 96...
wish i could find the scans of it.. i had so many ask for copies of it i had a webpage with them as the webpages back then... i bet its with my how to keep your rabbit alive book... buried.. hell i had guys email that worked for bae and help devolop the kt.. :P
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I side with CRS on the Oil line. Even if oil builds inside the line because it is lower than the level in the pan it won't take much to make it get above that level and create some head pressure and drain on down. You might find that when you ever go to take the line off and the oil level is up some will be leaking out when you do so. Something tells me this is not going to be a routine thing by any means. My concern on loose line is that it may catch something someday. A cardbox box, a small stick, a small child? I just like things secure that is my method at least for stuff under the car.
I have played with the push on lines when I did my WVO system. Yes must be cut off with knife. Getting them on I found a little warmth helped with that.
Later
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I can see some potential problems with having the turbo oil draining below the level of the oil. When it's cold, it will take more pressure to overcome the viscosity of the oil inside the drain hose, and that's on top of the pressure required, (minimal but still there), to overcome the hydrostatic pressure of having the oil level above the drain outlet.
There is also a chance crankcase pressure could push oil back up the drain hose.
On the other hand, these are just guesses from my often paranoid mind.
ps...that WAIC blows my mind.
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Thanks for the replies and agree that when it's cold, the oil returning into the crankcase oil may have some resistance. As far as tying the drain line down, It's not lower than the flat-bar connecting the mount braces so I'm not concerned about it snagging anything.
Here is a clearer shot of the drain line.
(https://lh6.googleusercontent.com/-uBm7ImVIYt0/UkdSRyIUq6I/AAAAAAAACIA/aqRYEBRt5uw/w869-h652-no/DSC00651.JPG)
If I could find a small pump to create a vacuum, I'd install it. I know it sounds crazy but I simply can't have any getting past the turbo seals and into the intake.
Has anyone heard of a small 12V pump that could handle the heat from the oil?
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You're probably going to be fine...I was just looking at worst case scenarios. The seals in a turbo are more than just slingers since they have to isolate the bearings from the boost and drive pressures, and contain the oil pressure.
Even though the drain doesn't technically need to be pressurized, any oil going up the drain tube would have to overcome the pressure of the oil being fed to the bearings. That will always be more than hydrostatic and I imagine any crankcase pressure, unless your venting was plugged or inadequate in the first place.
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You're probably going to be fine...I was just looking at worst case scenarios. The seals in a turbo are more than just slingers since they have to isolate the bearings from the boost and drive pressures, and contain the oil pressure.
Even though the drain doesn't technically need to be pressurized, any oil going up the drain tube would have to overcome the pressure of the oil being fed to the bearings. That will always be more than hydrostatic and I imagine any crankcase pressure, unless your venting was plugged or inadequate in the first place.
Good point - don't really want to add another pump, wire, fuse etc if I don't have to. This thing is tuning into the space shuttle as it is - I just hope it runs soon.
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I don't think you have much to worry about with your drain. If you''re getting oil in your turbo, it's more likely to come from bad seals or an upstream crankcase vent than pushback from the drain hose.
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Gizmo, I think your drain will not be an issue provided the stock oil drain fitting on the turbo is the smallest ID anywhere on the drain. Having a large ID to the drain is the best way to keep the shaft seals from leaking. I wish your drain was closer to 6:00 but I understand the limitations. That said, my K14 AAZ drain is at 6:00...
You're probably going to be fine...I was just looking at worst case scenarios. The seals in a turbo are more than just slingers since they have to isolate the bearings from the boost and drive pressures, and contain the oil pressure.
Even though the drain doesn't technically need to be pressurized, any oil going up the drain tube would have to overcome the pressure of the oil being fed to the bearings. That will always be more than hydrostatic and I imagine any crankcase pressure, unless your venting was plugged or inadequate in the first place.
I do not think there is drive pressure at either of the shaft seals. The air is in motion and so inertia, centrifugal force and Bernoulli's principle have a large effect.
The oil pressure fed to the bearings does not push against the drain. If it did, the shaft seals would leak. The drain is purely gravity flow.
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I rebuilt the turbo and it now has the 360 bearing and new "seals". I aslo clocked the housing to drain exactly at 6:00 - prior to the rebuild it was at about 4:00 and possibly the reason it had a good film in it.
I may forgo the catch can as it seems to be more hassle than I want to add right now.
I do need to build an air cleaner housing so I may send my blow-by to the pre-filter side in the design of the box. The good thing would be a slight vacuum would insure positive crankcase venting and if there is oil in it, it will get caught in the filter before it clogged up the manifold.
I'd much rather change filters more often than remove the intake.
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Gizmo, I think your drain will not be an issue provided the stock oil drain fitting on the turbo is the smallest ID anywhere on the drain. Having a large ID to the drain is the best way to keep the shaft seals from leaking. I wish your drain was closer to 6:00 but I understand the limitations. That said, my K14 AAZ drain is at 6:00...
You're probably going to be fine...I was just looking at worst case scenarios. The seals in a turbo are more than just slingers since they have to isolate the bearings from the boost and drive pressures, and contain the oil pressure.
Even though the drain doesn't technically need to be pressurized, any oil going up the drain tube would have to overcome the pressure of the oil being fed to the bearings. That will always be more than hydrostatic and I imagine any crankcase pressure, unless your venting was plugged or inadequate in the first place.
I do not think there is drive pressure at either of the shaft seals. The air is in motion and so inertia, centrifugal force and Bernoulli's principle have a large effect.
The oil pressure fed to the bearings does not push against the drain. If it did, the shaft seals would leak. The drain is purely gravity flow.
Thanks libby, I was hoping you chime in. My drain is at 6:00 - took a lot of fiddling but I made it. I believe you were the one who pointed it out almost a year ago when I started my re-build. After trying several concepts, I ended up machining a custom banjo fitting. I know it doesn't look like it in the photo but it is definitely at 6:00 (turning an abrupt 90 at the banjo). My drain hose is #8 JIC/AN fittings which I believe is 1/2" ID so that should do it.
Here's a shot of the drain. . .
(https://lh5.googleusercontent.com/-peuQwJyFbrY/UU3bmd3br5I/AAAAAAAABj0/_ld1FfwjiGo/w869-h652-no/DSC00382.JPG)
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I do not think there is drive pressure at either of the shaft seals. The air is in motion and so inertia, centrifugal force and Bernoulli's principle have a large effect.
You might be right on the intake side of the turbo but there is always pressure on the turbo side and oil pressure at the bearing.
The inlet of the turbo will have something of a vacuum, and the outlet will be pressurized. Both the inlet and the outlet of the exhaust side will be pressurized so it seems to me that it's likely the seal will also be pressurized and the oil entering the bearing is pressurized, though the outlet isn't.
I'm mostly speculating since I don't have any data but it's an area I haven't thought too much about before but it's interesting, and I'm more than happy to be proven wrong to learn something new.
Isn't fluid dynamics fun?
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You have to remember too that your cores will have x psi running through them. If you go say 15psi then there will be 15psi blowing through them. It won't be the same as shop air blowing through, but if one does plug then it will be more forceful as there will be less volume for the same 15psi to go through. I don't see it being an issue of the cores plugging up in the intake. If you had an EGR then yes it would be a nightmare, but the oily residue should pass right though I am figuring.
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Hmmmm,
I had planned (and have all the stuff for) a water/meth injection system. Maybe the 50/50 mix would keep the Laminova cores clean? I decided not to install it due to having to find or make the mix when traveling long distances.
Another solution would be to build another intake with more accessible cores. I guess for now, I'll just see how this goes.
Has anyone seen a turbo without oil in the intake? I only have experience with this one and there was plenty of it when I started the rebuild. However, the vent was plumbed into the intake piping and it was clocked at 4:00 as well. The turbo itself was in great shape. I only rebuilt it cause I had time while waiting for parts to arrive. Besides, I wanted to replace the stock bearing with the 360.
Forgive me for doubting your perspective libby but as a machine designer by trade, it's tough for me to not look for weaknesses, and try to bring solutions before release. I'm not confident the designers of the turbo were trying to achieve a 100% seal against oil leakage - which is what is needed if I don't want the cores getting oiled up.
That said, I'm not sure that a bit of oil would be that big of an issue :-\
Thanks Theman, I just read your post while I was writing this, it seems were both on a similar track (based on my last sentence) ;)
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all turbos have oil in them from breather vent....
go pull your breather pipe from a td.. stick it in a jug.. clear plastic with some paper towel in it.. see how it splatters/vaporos oil in the pvc system...
if you see droplets on towel.. decide if too big... then rember the turbine makes it a mist...
but all you can do is try it...
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That's why I plan in running my vent pre-intake filter. It may oil the filter but not much should get past it.
When I design the filter box, I'm going to keep the vent in mind and make it so there's a catch area of sorts with a drain on it.
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My truck just came with a catch can...a crappy system but satisfied the problem of crankcase ventilation without too much mess. The problem was, it did make a mess...just on my rad and engine. It was at the front of the engine and the fan would blow oil everywhere. Kept it off the ground, for the most part.
I now just run a tube down below the engine. As I've mentioned before, there are no emissions restrictions on my pickup so I can get away with it. I am planning on an oil/air seperator...as soon as I design it. In the meantime, the oily film on the bottom of my truck is doing a fine job of preventing rust.
If you have the crankcase vent upstream of the turbo, you will get oil on it...there's no way to avoid that. You could reduce that somewhat with an air/oil seperator midstream, or like you're doing, pre air filter.
You could put a couple of baffles in the filter box at the vent outlet, (I'm thinking one of those copper scrub pads in a soup can kind of thing), and rig a drain for the collected oil, if you want to keep your filter cleaner longer.