FredG Posted October 15, 2012 Report Share Posted October 15, 2012 Two corrections: First, I meant to ask: "The question remains, given the contradictory names of the chapter and the section, do they mean whenever scheduled maintenance or unscheduled maintenance is carried out?" Also, apparently, when a "b" is followed by a ")", you get a . Who knew. fg Link to comment Share on other sites More sharing options...
Roger Lee Posted October 15, 2012 Report Share Posted October 15, 2012 The oil analysis schedule is taught in Rotax school, too. I know this is off topic. Here is just a quick note on oil, Full Synthetic will not suspend lead and it will fall out in the gearbox and crankcase and other places you don't want it. A semi synthetic will suspend the lead, but it can't get it all. You should be using a product like Decalin (a lead scavenger) to help reduce lead deposits in the engine with 100LL. You should be running a little higher cruise rpm to help keep the lead blown out. If you use 100LL can can see the grey lead color in the oil and if you pull the oil tank you will see the lead build up in the bottom of the tank. If you use 100LL more than 30% of the time and especially if you use it all the time you should pull the gearbox bat 600 hrs. to get the slipper clutch cleaned as set in the maint. manual. If you don't by about 800 hrs. the slipper clutch will have accumulated enough lead to make it non functional. Certainly you are better off if you only use 100LL 30% of the time verses 100%. There is nothing good about 100LL. Link to comment Share on other sites More sharing options...
FredG Posted October 15, 2012 Report Share Posted October 15, 2012 I don't think owners should have to know what it taught in Rotax class if it's not in the most recent Maintenance Manual. I find it hard to even understand how a particular maintenance practice can be required if it's not in the Maintenance Manual. Like I said, I like the engine but the documentation is less than perfect. Link to comment Share on other sites More sharing options...
Roger Lee Posted October 15, 2012 Report Share Posted October 15, 2012 Hi Fred, That's why we should take a class. Things get lost in translation from Austria, current practices take a long time to get in the books and translations may mean one thing, but get translated just a tad different. A lot of things aren't required it's just doing things better to help preserve the longevity of the engine. How many have an oil change in their auto manual that has never been looked at. Then how many actually follow the manuals oil schedule for their car. How about the hose change for a car that is in the auto manual? How many of you get any updates at all about your car after it was new or the changes in maint work? There are usually a lot of them. How many follow what the oil Mfg says. i.e. change it only every 15K miles? It's not any different. Same thing. It's just keeping up and taking the time to do the research. Link to comment Share on other sites More sharing options...
Doug G. Posted October 16, 2012 Report Share Posted October 16, 2012 At least we know who to hold legally responsible if the poor translations cause serious issues. As far as your auto questions - I do. Although I change my synthetic oil at 5k instead of the mfgs. 7k or the garage's 3k! Before I have them serviced I search online for any fixes available. I have not had any problem reading my manuals either from Ford, or Nissan. They evidently found people who knew two languages - maybe even an English linguist or grammarian. Link to comment Share on other sites More sharing options...
Doug G. Posted October 16, 2012 Report Share Posted October 16, 2012 I would also suggest that if the classes are that important to the maintenance of these engines, Rotax should offer them free - fter all, it is their reputation that is on the line. I think Bombardier could afford it. Link to comment Share on other sites More sharing options...
Roger Lee Posted October 16, 2012 Report Share Posted October 16, 2012 Being a foreign European company many things don't happen as they do in the US, responsibility and lawsuits included. Cultural differences do happen as the other US LSA distributors have found out the hard way. As far as classes, even auto and motorcycle dealers send their mechanics to school and don't rely on just manuals. They to have found out the hard way over the many years. Screw ups and lack of education are expensive. I think we have pretty well beat this one to death. Link to comment Share on other sites More sharing options...
Doug G. Posted October 16, 2012 Report Share Posted October 16, 2012 At least until next time. Link to comment Share on other sites More sharing options...
Dan Kent Posted October 16, 2012 Author Report Share Posted October 16, 2012 Dan, I use Mogas only but I see that there is a thin layer of lead "sludge" on the bottom of my reservoir when it is removed and cleaned. Not sure why because the Mogas isn't supposed to have lead. Perhaps there's some lead in "non-leaded" Mogas? I know that eventhough it is supposed to be "low lead", 100LL fuel has a lot of lead in it so perhaps Mogas has some? There are guys on this thread that have commented on the chemical makeup of fuel and perhaps they could comment on this. Removal and cleaning of the oil reservoir may be optional if Mogas is used because there isn't much lead found. Just another low cost preventative thing to do. The bottom line is I hope that all is well with your Rotax and there are no problems. A comment on lab testing. The diesel engine durability department where I worked before retiring used chemical oil analysis as one of the main tools to evaluate new engine designs or cost reduction changes to existing engines. Running compressed durability on dynomometers, oil analysis is used as an early indicator to determine if unacceptable wear may be ocuring. Part wear analysis at teardown inspection normally supported the oil analysis. Thanks Dick. I intend to have another oil analysis done at the next oil change and will post those results. Link to comment Share on other sites More sharing options...
FlyRatz Posted October 16, 2012 Report Share Posted October 16, 2012 Hi FredG, I am a native German speaker and I checked the authorative German document. As far as I can see, the english translation is at least "unlucky". The heading of the section in question in the German manual is "Sonderkontrollen". In the english manual the heading is "Unscheduled maintenance checks". This translation is misleading you because the German word has no meaning in a time aspect. A better translation for the German heading would be: "Special checks". The meaning of "special" here is the same as in "special occasions" This is the reason for the absence of oil analysis in the table of "Scheduled Maintenance Checks". Simply it is not scheduled. But it is recommended to gain more details about the wear of the engine. Roger already explained the benefits of oil analysis and I will bring another aspect to the discussion. A mechanical engineer knows, that every mechanical engine has a specific amount of wear. This specific amount is not constant over the lifetime of an engine and depends on the time and load, the engine has already run. A typical wear curve over time will look like the curve in the attached picture. You will see, that the wear is high in the beginning and decreases until a inflection point is reached. Beyond this point the wear is minimal and it increases very little with time. At the right side of the curve you will see a second inflection point. At this point, the wear starts to increase and starts to raise very high. This process ends with the end of the engines life. A good maintenance wants to know, when this second inflection point is reached. Because beyond this point, the likelyhood of a engine failure becomes higher and higher. The only tool to find this point is oil analysis on a regular basis. N.b. Rotax set the TBO o 2000 hrs, because they know, that the second inflection point lies beyond 2000 hrs of operation (usually). Markus Link to comment Share on other sites More sharing options...
FredG Posted October 17, 2012 Report Share Posted October 17, 2012 Markus, thanks for the translation. I appreciate your point about engine wear. For what it is worth, I understand that the metals in the oil came from parts of the engine that have worn during operation. Here is what no one has offered, a clear explanation of what is done differently as a function of oil analysis results. As far as I can tell, if required maintenance is done as specified, then nothing is done differently as a result of oil analysis. People like to get it, but nobody explains what they actually do with it. In reference to your attached figure, at what point does oil analysis tell you to take the engine out of service? To split the cases and replace the bearings? To replace the cam? Does oil analysis tell you when the engine is unreliable? If you like it, get it. But the suggestion that not getting it is bad maintenance has yet to be justified. Link to comment Share on other sites More sharing options...
C ICEY Posted October 17, 2012 Report Share Posted October 17, 2012 I'm doing an oil analysis fairly regularly. Seven now in 1000 hrs. The most noticeable change for me has been a steady decrease in lead, as I haven't used any LL now for about 700hrs. same procedure each time: warm engine, drain oil and sample midstream. Everything is running fine and all the other numbers are steady. When I get to TBO and the numbers still look fine, compression is still good, and everything is running great, then I'll keep running on condition. Someday, downwind, when the metals numbers start to inflect to a new trend, and I'm well past TBO hours (which every indication presently suggests will occur), yet everything appears to still be running fine, then I'll know its starting to be time to take a closer look and consider the overhaul, as something has begun to change.... I think that having enough analyses over time to establish trends is the important part. Meanwhile, I keep the carbs and prop in good balance. mind the mag plug, mind the compression, mind the oil analysis, mind the sparkplugs, mind the exhaust residue. long may you run! Link to comment Share on other sites More sharing options...
FlyRatz Posted October 17, 2012 Report Share Posted October 17, 2012 ... But the suggestion that not getting it is bad maintenance has yet to be justified. Hi FredG, it was not my intention to say, that a maintenance without oil analysis is a bad maint. If one follows the maintenance plan as required, everything is OK. If another one will do the maint as best as possible, he takes oil analysis into consideration. If you open your oil filter and check your magnetic plug every 100 hrs of operation, you will find a upcoming extensive wear very likely. The point is, that extensive wear which has already developed to produce swarfs, which then can be found in the oil filter, is in a advanced stage. Swarfs usually damage other bearings, before they make it to the filter. With oil analysis you are able to catch a extensive wear long before the swarfing stage is reached. It is a matter of taste. Happy landings Markus @C ICEY: Full ack Link to comment Share on other sites More sharing options...
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