Massive smoke-986S
#16
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Don't bet on it. For years, Pelican has been selling aftermarket parts as "OEM Supplier" parts, which is why my shop does absolutely no business with them. I'd be willing to bet that if you connected a digital manometer to your oil fill cap opening, you would find that their so called OEM part has failed.
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Don't bet on it. For years, Pelican has been selling aftermarket parts as "OEM Supplier" parts, which is why my shop does absolutely no business with them. I'd be willing to bet that if you connected a digital manometer to your oil fill cap opening, you would find that their so called OEM part has failed.
You wrote in another thread the following "Sometimes this may only happen in certain corners, and not in others. Problem stems from too much oil being retained in the upper engine area (read cam covers), where it cannot drain down fast enough through the M96's oil scavenging system, and the AOS becomes overwhelmed. This is one of the reasons Porsche developed the X51 package, which uses a "northwest passage" extra scavenging system to get the oil back down where it belongs."
I realize this is slightly out of context for this thread but wonder if you could flesh out your comment about the AOS being overwhelmed by excess oil pooling in the heads. I'm a bit dense but I don't see the connection as both the AOS and the scavenger pumps are depositing oil back to the sump which should be doing nothing more than raising the level in the sump.
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Is the smoke out the tailpipe, or just out the back? Have you checked your cam plugs? Those green (or black) plugs can become unseated or even pop out. I locked my cams once and missed pressing one in all the way. Under hard acceleration the oil spits out onto the header & cat leaving a smoke trail (and near heart failure). This is consistent with your hard acceleration up hill too.
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DSC has viable comment and worth a consideration at least. Ill ask a common sense ? oil condition? type? using the same all the time?. Scavenger pump falling short at high RPM? I took a minute to look at a few things it appears the AOS sits at the Rt rear of the motor yes? From some diagrams it also appears the AOS actually has a spout/pipe/fitting that goes into the upper portion of the crankcase. Please correct me if Im wrong. Ill assume that the oil vapor/residue drains back to the crankcase at that point. Being at the rear of the motor I could get my mind around hard accel on a incline would put the oil in the back corner and up the spout for consumption. Let me ask another ? how long have you had the car. Joined 2020 and have 8 posts. Im not sure how the count thing works and not picking on you but more insight. Did this just start? When was the last oil change? You say about a qrt low what is the oil lever hot?
Last edited by Gasngo; 01-24-2023 at 12:28 AM.
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Is the smoke out the tailpipe, or just out the back? Have you checked your cam plugs? Those green (or black) plugs can become unseated or even pop out. I locked my cams once and missed pressing one in all the way. Under hard acceleration the oil spits out onto the header & cat leaving a smoke trail (and near heart failure). This is consistent with your hard acceleration up hill too.
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DSC has viable comment and worth a consideration at least. Ill ask a common sense ? oil condition? type? using the same all the time?. Scavenger pump falling short at high RPM? I took a minute to look at a few things it appears the AOS sits at the Rt rear of the motor yes? From some diagrams it also appears the AOS actually has a spout/pipe/fitting that goes into the upper portion of the crankcase. Please correct me if Im wrong. Ill assume that the oil vapor/residue drains back to the crankcase at that point. Being at the rear of the motor I could get my mind around hard accel on a incline would put the oil in the back corner and up the spout for consumption. Let me ask another ? how long have you had the car. Joined 2020 and have 8 posts. Im not sure how the count thing works and not picking on you but more insight. Did this just start? When was the last oil change? You say about a qrt low what is the oil lever hot?
2. Agree with your description of AOS system except vapor goes to intake and oil goes back to crankcase ---probably what you meant to say
3.Hard to imagine the oil being slushed up the AOS downspout...more likely the oil isn't draining fast enough through the downspout and causing the AOS to get swamped
4.I've owned the car for 15 years and 100K miles and I change the oil and filter every six or eight months and I always check the oil level when the engine is warmed up and car is level.
5. The smoke problem first occurred about a month ago and I can produce it at will ...hard acceleration up hill.
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Actually I can imagine a lot a things. Only by looking at some images and drawings that I came to the conclusion that the AOS at the rear of the motor might just get a spike of oil. I dont know what the inside of the crankcase looks like where the spout is inserted is there a shelf or baffle to deflect anything for that reason. The manometer was mentioned up above cant say I have ever used one for this purpose but can you extend the hose into the cab and test drive the car. I would be curious what you get from and what it influences. Food thought. As I learn more Ill pitch my thoughts out there.
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I'd be suprised if there is not something wrong / broken that causes the smoke you're seeing. Can't imagine this to be design flaw, sice I have been tracking my 2001 Boxster 2.7 (manual) now 2 years and couple of tracks have steep uphills (kind of like Bathurst) that we'll drive full throttle and the car has never yet shown smoke clouds on the track regardless of the rpm. My 2.7 is stock, but I installed 2 years ago Porsche OEM AOS.
Last edited by pilot4fn; 01-26-2023 at 12:46 AM.
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While I still do not have a definitive answer as to why my car smokes as described earlier, i would like to share how I solved the problem. The more I thought about the problem the more convinced I became that oil is being sloshed up into the large breather tube (the one with the diagonally shaped end) and I begin thinking about how to prevent this from happening without messing up the crankcase vacuuming action. My inspiration came in watching Aaron on the Youtube channel Help Me DIY as he installed the "ultimate AOS". I saw that what looked like an hummingbird's nest had been installed in the breather tube and Aaron provide the information that it was copper wire mesh and the mfr provides it to enhance the AOS process. Why....I thought, couldn't I do something similar to retard the sloshed oil? So, turning to Amazon ( "copper mesh roll, sturdy pure copper stuff-fit wire mesh for gap blocker fill fabric 4" X 40") I squandered ten bucks and turned the 4'' wide roll into a very tightly rolled cylinder which was then shoved up the breather tube. I should mention that the mesh cylinder was 20-25 % larger in diameter than the ID of the tube so it took some serious pushing and shoving to get it in place. I should also mention that before taking this step i stuffed the mesh cylinder into a short piece of pipe and tried breathing through it to get some idea as to how much it might restrict air flow. As it turns out, there was no noticeable restriction. (not very scientific, I know) In hindsight I wish I had drilled thru the tube and mesh cylinder and placed a piece of stiff copper wire thru the assembly to insure that the mesh could never become dislodged. With the AOS re-installed and the engine running I was relieved to see no change in crankcase vacuum measured with a tube manometer. And, I was even more relieved that after several vicious attacks on my favorite hill, the smoking problem was no more. I have since put about a 1000 miles on the car and I'm pretty confident that my fix is safe and reliable BUT...don't take my word for it. If you are thinking about trying this please remember that I am not a professional mechanic or mechanical engineer and most of the time I don't know what I'm doing. PROCEED AT YOUR OWN RISK
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While I still do not have a definitive answer as to why my car smokes as described earlier, i would like to share how I solved the problem. The more I thought about the problem the more convinced I became that oil is being sloshed up into the large breather tube (the one with the diagonally shaped end) and I begin thinking about how to prevent this from happening without messing up the crankcase vacuuming action. My inspiration came in watching Aaron on the Youtube channel Help Me DIY as he installed the "ultimate AOS". I saw that what looked like an hummingbird's nest had been installed in the breather tube and Aaron provide the information that it was copper wire mesh and the mfr provides it to enhance the AOS process. Why....I thought, couldn't I do something similar to retard the sloshed oil? So, turning to Amazon ( "copper mesh roll, sturdy pure copper stuff-fit wire mesh for gap blocker fill fabric 4" X 40") I squandered ten bucks and turned the 4'' wide roll into a very tightly rolled cylinder which was then shoved up the breather tube. I should mention that the mesh cylinder was 20-25 % larger in diameter than the ID of the tube so it took some serious pushing and shoving to get it in place. I should also mention that before taking this step i stuffed the mesh cylinder into a short piece of pipe and tried breathing through it to get some idea as to how much it might restrict air flow. As it turns out, there was no noticeable restriction. (not very scientific, I know) In hindsight I wish I had drilled thru the tube and mesh cylinder and placed a piece of stiff copper wire thru the assembly to insure that the mesh could never become dislodged. With the AOS re-installed and the engine running I was relieved to see no change in crankcase vacuum measured with a tube manometer. And, I was even more relieved that after several vicious attacks on my favorite hill, the smoking problem was no more. I have since put about a 1000 miles on the car and I'm pretty confident that my fix is safe and reliable BUT...don't take my word for it. If you are thinking about trying this please remember that I am not a professional mechanic or mechanical engineer and most of the time I don't know what I'm doing. PROCEED AT YOUR OWN RISK
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When you say "breather tube", do you mean the tube that sits horizontal on top of the engine... connected from the top of the AOS to the throttle body/intake?When you say "... shoved up the breather tube"... do you mean "in the breather tube"? Emphasis on the word "in". I'm trying to understand your "up the breather tube" comment because, again, and if it's the correct tube, that tube sits horizontal... not vertical (up).
Please, help me understand. Thank you.
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And as for the copper mesh cylinder, think feminine hygiene products. It's a tightly rolled cylinder 4''in length and somewhat oversized so it had to be be stuffed up into the "tube". I'd include a photo if I knew how but in any case there is nothing to see because the mesh cylinder is inside the AOS! Clear now?