Houman Posted July 10, 2015 Report Posted July 10, 2015 Just got my 1st oil analysis from BlackStone, I'm not sure what metal my cylenders are made of ( I know I should know, I have the continental Overhaul information sheet, with cylenders S/N, but not what they are made of ). What do you guys think, it is my 1st oil analysis, and not any bad news, but just curious. P.S. The engine is the Rocket Converted TSIO 520NB 17B 305 HP Thanks... Quote
M20S Driver Posted July 10, 2015 Report Posted July 10, 2015 IMO oil analysis is more for trending the behavior of your engine than anything else. Your numbers look fine to me. My lead numbers are usually higher (like yours) since I run 75 deg ROP in my flights that are ususally less than one hours. I am not sure about the phosphorus number. I may be from some additive or lubricant. 1 Quote
Danb Posted July 10, 2015 Report Posted July 10, 2015 Great start for your trend analysis..I get mine sent in next week, I hope mine are as good as yours.. Quote
KSMooniac Posted July 10, 2015 Report Posted July 10, 2015 Just keep flying and sampling to establish what is normal on your engine. Quote
Houman Posted July 10, 2015 Author Report Posted July 10, 2015 Well in this case sample was taken at annual during oil change, mid flow, the plane had not been flown for about 10 days since the sample, and I did inform them of that, they said it is ok, they will take it under consideration... Quote
Jeff_S Posted July 14, 2015 Report Posted July 14, 2015 It's amazing how your test is tracking your unit averages! But seriously, any one sample isn't going to tell you much, which is why you should get it tested with every oil change. Blackstone also does a real good job telling you what they've found and pointing out anything that merits further attention or investigation. I remember back when I had my Cherokee, I went almost 50 hours between changes because I was tooling around out West and then up to Osh, and I decided just to "fly the crap" out of it before I did a change. That particular sample showed a spike in iron, but because I told them about my "fly the crap out of it" strategy they suggested this was probably just some older corrosion that was finally getting knocked off and nothing to worry about. Sure enough, the next sample the iron content had dropped below the prior baseline. Quote
jetdriven Posted July 14, 2015 Report Posted July 14, 2015 All those wear metals and Silicon all track with hours. So its really not the raw nuumber that matters, but the PPM per 50 hours. Normalize all the values to 50 hours to get meaningful data. Quote
Houman Posted July 14, 2015 Author Report Posted July 14, 2015 Well I do oil change every 25 to 30 hours of air time, so about 35h to 40h of engine time. As it says in Rocket Engineering documentation, oil is cheaper than an engine... Quote
Piloto Posted August 14, 2015 Report Posted August 14, 2015 I prefer the oil filter inspection. The filter paper element collects all the particles through between oil changes while the oil sample is filtered oil from the last run. José 1 Quote
Houman Posted August 14, 2015 Author Report Posted August 14, 2015 yeah, I have not done that since my mechanic is always very eager to open it up and see what is in it.... Quote
DXB Posted August 14, 2015 Report Posted August 14, 2015 When I do my oil change, I've been cutting my own filter and also sending oil sample to Blackstone. I know there are companies that will analyze the particulates in the filter itself by scanning EM and X-ray diffraction. At $60 a pop, it is probably excessive to do each time, but has anyone done this occasionally for extra peace of mind? http://www.avlab.com/ProductDetails.asp?ProductCode=ga-f-l It's probably the way to go if you are seeing stuff in the filter but don't know what it is. Quote
ArtVandelay Posted August 14, 2015 Report Posted August 14, 2015 I prefer the oil filter inspection. The filter paper element collects all the particles through between oil changes while the oil sample is filtered oil from the last run. José It collects all the larger particles (30-40 microns), the smaller ones are suspended in the oil. If you have metal in the filter and wanted to figure where it's coming from, filter analysis is the way to go. To insure a good representative sample of the oil, pull it after flying, and you will pick up on wear before it becomes big enough to be collected in the oil filter. Quote
PaulB Posted August 14, 2015 Report Posted August 14, 2015 What about the oil screen? Do the J models have a screen and if they do do you check that with every change? My understanding is that they catch the bigger particles. Quote
DXB Posted August 14, 2015 Report Posted August 14, 2015 It collects all the larger particles (30-40 microns), the smaller ones are suspended in the oil. If you have metal in the filter and wanted to figure where it's coming from, filter analysis is the way to go. To insure a good representative sample of the oil, pull it after flying, and you will pick up on wear before it becomes big enough to be collected in the oil filter I've garnered from Mike Busch's writings that the oil analysis is good at picking up wear metals from top end problems early. However, according to him, sometimes cam/lifter spalling issues will just show up suddenly as visible metal in the filter one day without any warning in the oil analysis. So I guess the two are complementary, but if I only did one, I'd stick to cutting the filter. 1 Quote
Andy95W Posted August 15, 2015 Report Posted August 15, 2015 I've garnered from Mike Busch's writings that the oil analysis is good at picking up wear metals from top end problems early. However, according to him, sometimes cam/lifter spalling issues will just show up suddenly as visible metal in the filter one day without any warning in the oil analysis. So I guess the two are complementary, but if I only did one, I'd stick to cutting the filter. +1. Airplanes went to TBO nicely before oil analysis ever existed. And since we're not talking about a fleet operator trying to get an extra 100,000 miles out of his diesel trucks, or an airline trying to get an extra 1000 hours before overhaul, I wonder how beneficial it really is for our airplanes that are run relatively infrequently. Then again, if it adds to one's peace of mind, I would never tell someone they shouldn't. Quote
DonMuncy Posted August 15, 2015 Report Posted August 15, 2015 According to Mike Busch, the big chunks are caught in the screen, the smaller stuff is caught in the filter and the eensy stuff is discovered by oil analysis. Theoretically, if the pieces are small enough to escape the filter, they aren't going to ruin things immediately. but you want to know that they are there, and you want to know where they came from. So you really need to check all three It is good to go to Savvy Aviation and read the archived webinar about oil. Quote
Andy95W Posted August 15, 2015 Report Posted August 15, 2015 Yeah, I get that. I had my first Mooney on oil analysis for years but ultimately realized I wasn't doing anything with the results other than fly another 20 hours and resample, at which point it comes back normal. Got an Aztec and didn't see the sense in paying twice as much for information I wasn't using. I wonder what other A&Ps besides me are doing with their airplanes and oil analysis. Clarence? Cliffy? David? Byron? But again, I'm not faulting anyone for doing oil analysis. As I've said before, peace of mind is worth a lot. Quote
Piloto Posted August 15, 2015 Report Posted August 15, 2015 It collects all the larger particles (30-40 microns), the smaller ones are suspended in the oil. If you have metal in the filter and wanted to figure where it's coming from, filter analysis is the way to go. To insure a good representative sample of the oil, pull it after flying, and you will pick up on wear before it becomes big enough to be collected in the oil filter. Where do you take the oil sample, at the dipstick or at the drain? I guess it will make a significant difference where the sample is taken. Specially if you added oil recently. Metal particles do not float in oil, they just sink. I just use a magnet and a magnifying glass to identify the particles in the filter. José Quote
ArtVandelay Posted August 15, 2015 Report Posted August 15, 2015 Where do you take the oil sample, at the dipstick or at the drain? I guess it will make a significant difference where the sample is taken. Specially if you added oil recently. Metal particles do not float in oil, they just sink. I just use a magnet and a magnifying glass to identify the particles in the filter. José If you do it just after a flight, I pull it from the dipstick, the oil and anything in it will be well blended. In the aviation world, it seems like a cheap diagnostic tool for a vital part of your airplane, in addition checking screen and filter. Quote
jetdriven Posted August 15, 2015 Report Posted August 15, 2015 What do you use to get it from the dipstick? Quote
DXB Posted August 15, 2015 Report Posted August 15, 2015 What do you use to get it from the dipstick? My transition instructor, who is also an A&P, was a big fan of using this thing to draw through the dipstick: http://www.blackstone-labs.com/vacuum-pump.php He suggested using it at 25 hrs to check "condition of the oil" and decide whether to keep running it or change. Never made total sense to me, so thus far I've stuck to the "oil is cheaper than an engine" philosophy every 25-35 hrs. Quote
carusoam Posted August 15, 2015 Report Posted August 15, 2015 Dev, The link went to the web site. I did not see a device, if that is what you were trying to point at. I did find their FAQs. Those people have a sense of humor! Best regards, -a- Quote
Guest Posted August 15, 2015 Report Posted August 15, 2015 Yeah, I get that. I had my first Mooney on oil analysis for years but ultimately realized I wasn't doing anything with the results other than fly another 20 hours and resample, at which point it comes back normal. Got an Aztec and didn't see the sense in paying twice as much for information I wasn't using. I wonder what other A&Ps besides me are doing with their airplanes and oil analysis. Clarence? Cliffy? David? Byron? But again, I'm not faulting anyone for doing oil analysis. As I've said before, peace of mind is worth a lot. I sample both of my planes every other oil change(25 hours) in the shop we take an oil sample with every oil change, it is taken as quickly as possible while the hot oil is draining into the bucket. If the customer does not want the sample sent in we discard it. We cut open all oil filters for examination and a pass through with a magnet, any suspect filters are bagged and tagged for comparison to the next filter. We have sent filters out to a company for examination on occasion. Clarence Quote
ArtVandelay Posted August 15, 2015 Report Posted August 15, 2015 What do you use to get it from the dipstick? This http://www.amazon.com/Hopkins-10111-FloTool-Mixmizer-Injector/dp/B000G72U0K I attach it to the plastic tubing that came with the kit and draw it like you would if taking a blood sample. Quote
DXB Posted August 15, 2015 Report Posted August 15, 2015 Yeah, I get that. I had my first Mooney on oil analysis for years but ultimately realized I wasn't doing anything with the results other than fly another 20 hours and resample, at which point it comes back normal. Got an Aztec and didn't see the sense in paying twice as much for information I wasn't using. I wonder what other A&Ps besides me are doing with their airplanes and oil analysis. Clarence? Cliffy? David? Byron? But again, I'm not faulting anyone for doing oil analysis. As I've said before, peace of mind is worth a lot. I'm curious as well. There do appear to be reputable, experienced A&Ps who are anti-oil analysis, perhaps with good reasoning? I recall having a conversation with Joe Cole about this at my prebuy- he viewed oil analysis with disdain but generally sent it because of near-universal owner demand. He didn't say why, but for him I suspect it generates owner pressure to investigate small blips which are meaningless to the health of the engine most of the time. On the flip side, appropriately not recommending immediate action on an uninterpretable change that is later followed by a catastrophic failure may generate liability. Routine oil analysis is a screening test- conceptually close to health screening tests, which do have risks. Inadequately sensitive screening tests provide false peace of mind. Inadequately specific ones lead unnecessary interventions, which can be harmful. Classic example is the 15 years of routine PSA screening that happened for prostate cancer, which lacked specificity for the tiny subset of prostate cancers that actually mattered. As a result very very few men were actually helped. But there are now a whole lot of guys impotent, or worse, after prostate surgery for a tumor that would have never hurt them. In the meantime the makers of the test got rich. Primary care MDs universally screened - if you failed to screen and your patient got prostate cancer, you might get sued. And urologists and radiation oncologists made good money from treating the new deluge of prostate cancers that would have never otherwise been caught, so there was little incentive to think critically on the issue. Sorry for long digression. I've no idea if oil analysis leads to harm in the aviation world. My only point is that non-validated screening tests do certainly have the potential to cause harm; yet external pressures can still keep them in use for a long time. 1 Quote
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