---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Thu 02/02/12: 18 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:32 AM - Re: Re: Throttle Cables (Bob Harrison) 2. 01:58 AM - Re: burping the 912 (John Wighton) 3. 02:02 AM - Re: Official Europa-List Usage Guidelines (RCC Sky Mail) 4. 02:37 AM - Re: Re: burping the 912 (GRAHAM SINGLETON) 5. 03:32 AM - Re: Re: burping the 912 (Frans Veldman) 6. 04:34 AM - SV: Re: burping the 912 (Sidsel & Svein Johnsen) 7. 05:13 AM - Re: Throttle Cables (europapa) 8. 06:24 AM - Re: Re: Throttle Cables (Bob Harrison) 9. 08:15 AM - AW: Smart engine istalled in a EUROPA (uvtreith) 10. 08:19 AM - Re: Throttle Cables (europapa) 11. 08:58 AM - Pilot Handbook for XS tri gear (skanderup) 12. 09:53 AM - Re: Pilot Handbook for XS tri gear (G-IANI) 13. 09:53 AM - Re: AW: Smart engine istalled in a EUROPA (Fred Klein) 14. 10:13 AM - Re: Pilot Handbook for XS tri gear (Rowland Carson) 15. 01:29 PM - AW: AW: Smart engine istalled in a EUROPA (uvtreith) 16. 02:45 PM - Re: SV: Re: burping the 912 (Frans Veldman) 17. 03:48 PM - Re: SV: Re: burping the 912 (Robert Borger) 18. 04:35 PM - Re: SV: Re: burping the 912 (GRAHAM SINGLETON) ________________________________ Message 1 _____________________________________ Time: 12:32:37 AM PST US From: Bob Harrison Subject: RE: Europa-List: Re: Throttle Cables Hi! Juergen, It is my understanding that the original type of cables should always have been spring pulled to fully open (in the event of cable breaking ) at no time were they to be used in the "push" mode. In my opinion the most likely cables to be used to have a push or pull capability would be a Boden cable specifically designed for such application and also specifically length sized also, but as good as they are it would be unlikely that the existing springs would be suitable under such arrangement . Regards Bob Harrison G-PTAG . -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] On Behalf Of europapa Sent: 01 February 2012 15:30 Subject: Europa-List: Re: Throttle Cables As it goes I just replaced my cables last Sunday. (Believe it ore not, it took my 5 hours. ) I have been alarmed as the right carburetor did not fully open as I engaged the throttle in the cold hangar. The part outside of the housing bend instead of moving into the housing. Don't want to experience this during a flight! I also used high end bike parts (Jagwire) to replace them. (The original cables have got a very poor quality). I want to encourage at least the builders that have not already installed the cables that came with the kit to use a better quality ones. Now the cables are pulled by the carburetor spring instead of pushed by the throttle arm. Regards Juergen Read this topic online here: http://forums.matronics.com/viewtopic.php?p=365388#365388 ________________________________ Message 2 _____________________________________ Time: 01:58:42 AM PST US Subject: Europa-List: Re: burping the 912 From: "John Wighton" I attended the Rotax maintenance course held at the LAA in the UK. The burping process was discussed at some length, the conclusion being that unless you have no idea how much oil is in the engine - don't do it. The burping process simply returns oil to the tank. For a cold engine this means you are rotating and clearing oil off parts that really need all the oil they can get in the first seconds after start up. Except after an oil/filter change l do not burp my engine at all. I know the oil level in the tank when cold that corresponds to 'enough oil'. This procedure leaves oil in the engine and hopefully will result in less wear over it's life. The CDI RPM threshold is too high to enable hand crack starts of Rotax 912/914 engines. But that is no reason for complacency when turning the engine - always treat as live. John -------- John Wighton Europa XS trigear G-IPOD Read this topic online here: http://forums.matronics.com/viewtopic.php?p=365433#365433 ________________________________ Message 3 _____________________________________ Time: 02:02:33 AM PST US Subject: Re: Europa-List: Official Europa-List Usage Guidelines From: RCC Sky Mail Hi Matt Can you let me know when you expect the Bob Nucholls electrical book to ship to me following my List Contribution in November? Thanks Richard Churchill-Coleman On 2 Feb 2012, at 07:06, Matt Dralle wrote: > > Dear Listers, > > Please read over the Europa-List Usage Guidelines below. The complete > Europa-List FAQ including these Usage Guidelines can be found at the > following URL: > > http://www.matronics.com/FAQs/Europa-List.FAQ.html > > Thank you, > > Matt Dralle > Matronics Email List Administrator > > > > > ****************************************************************************** > Europa-List Usage Guidelines > ****************************************************************************** > > The following details the official Usage Guidelines for the Europa-List. > You are encouraged to read it carefully, and to abide by the rules therein. > Failure to use the Europa-List in the manner described below may result > in the removal of the subscribers from the List. > > > Europa-List Policy Statement > > The purpose of the Europa-List is to provide a forum of discussion for > things related to this particular discussion group. The List's goals > are to serve as an information resource to its members; to deliver > high-quality content; to provide moral support; to foster camaraderie > among its members; and to support safe operation. Reaching these goals > requires the participation and cooperation of each and every member of > the List. To this end, the following guidelines have been established: > > > - Please keep all posts related to the List at some level. Do not submit > posts concerning computer viruses, urban legends, random humor, long > lost buddies' phone numbers, etc. etc. > > - THINK carefully before you write. Ask yourself if your post will be > relevant to everyone. If you have to wonder about that, DON'T send it. > > - Remember that your post will be included for posterity in an archive > that is growing in size at an extraordinary rate. Try to be concise and > terse in your posts. Avoid overly wordy and lengthy posts and > responses. > > - Keep your signature brief. Please include your name, email address, > aircraft type/tail number, and geographic location. A short line > about where you are in the building process is also nice. Avoid > bulky signatures with character graphics; they consume unnecessary > space in the archive. > > - DON'T post requests to the List for information when that info is > easily obtainable from other widely available sources. Consult the > web page or FAQ first. > > - If you want to respond to a post, DO keep the "Subject:" line of > your response the same as that of the original post. This makes it > easy to find threads in the archive. > > - When responding, NEVER quote the *entire* original post in your > response. DO use lines from the original post to help "tune in" the > reader to the topic at hand, but be selective. The impact that > quoting the entire original post has on the size of the archive > can not be overstated! > > - When the poster asks you to respond to him/her personally, DO NOT > then go ahead and reply to the List. Be aware that clicking the > "reply" button on your mail package does not necessarily send your > response to the original poster. You might have to actively address > your response with the original poster's email address. > > - DO NOT use the List to respond to a post unless you have something > to add that is relevant and has a broad appeal. "Way to go!", "I > agree", and "Congratulations" are all responses that are better sent > to the original poster directly, rather than to the List at large. > > - When responding to others' posts, avoid the feeling that you need to > comment on every last point in their posts, unless you can truly > contribute something valuable. > > - Feel free to disagree with other viewpoints, BUT keep your tone > polite and respectful. Don't make snide comments, personally attack > other listers, or take the moral high ground on an obviously > controversial issue. This will only cause a pointless debate that > will hurt feelings, waste bandwidth and resolve nothing. > > - Occasional posts by vendors or individuals who are regularly > subscribed to a given List are considered acceptable. Posts by > List members promoting their respective products or items for sale > should be of a friendly, informal nature, and should not resemble > a typical SPAM message. The List isn't about commercialism, but > is about sharing information and knowledge. This applies to > everyone, including those who provide products to the entire > community. Informal presentation and moderation should be the > operatives with respect to advertising on the Lists. > > ------- > > > [This is an automated posting.] > > do not archive > > > > > > ________________________________ Message 4 _____________________________________ Time: 02:37:47 AM PST US From: GRAHAM SINGLETON Subject: Re: Europa-List: Re: burping the 912 I have a vague memory that the burping recommendation was something to do w ith checking that oil hadn't drained down into the sump=0Awhich might cause hydraulic lock. Could be other ways to check, such as quantity of oil in t he tank.=0AAnother vague memory, (sorry for the foggy thoughts!) is that on e chap in Devon or Cornwall regularly hand started his 912 so I=0Aam prepar ed to accept that hand starting is possible. Think about the gearing.-=0A Graham=0A=0A________________________________=0A From: John Wighton =0ATo: europa-list@matronics.com =0ASent: Thursday, 2 February 20 12, 9:52=0ASubject: Europa-List: Re: burping the 912=0A =0A--> Europa-List message posted by: "John Wighton" =0A=0AI attended the Ro tax maintenance course held at the LAA in the UK. =0A=0AThe burping process was discussed at some length, the conclusion being that unless you have no idea how much oil is in the engine - don't do it. =0A=0AThe burping proces s simply returns oil to the tank.- For a cold engine this means you are r otating and clearing oil off parts that really need all the oil they can ge t in the first seconds after start up.=0A=0AExcept after an oil/filter chan ge l do not burp my engine at all.- I know the oil level in the tank when cold that corresponds to 'enough oil'.- This procedure leaves oil in the engine and hopefully will result in less wear over it's life.=0A=0AThe CDI RPM threshold is too high to enable hand crack starts of Rotax 912/914 eng ines.- But that is no reason for complacency when turning the engine - al ways treat as live.=0A=0AJohn=0A=0A--------=0AJohn Wighton=0AEuropa XS trig ear G-IPOD=0A=0A=0A=0A=0ARead this topic online here:=0A=0Ahttp://forums.ma ============= ________________________________ Message 5 _____________________________________ Time: 03:32:44 AM PST US From: Frans Veldman Subject: Re: Europa-List: Re: burping the 912 On 02/02/2012 10:52 AM, John Wighton wrote: > The burping process simply returns oil to the tank. For a cold > engine this means you are rotating and clearing oil off parts that > really need all the oil they can get in the first seconds after start > up. Not true. The burping only moves oil that has dripped to the bottom of the crankcase to the oil tank. This oil is not participating in any lubrication at all. It is just sitting there in a useless pool at the bottom. Contrary, rotating the prop also turns the oil pump. This pumps new oil into all the bearings, so that when the engine starts there is fresh oil in the bearings. (The oil that was there previously has dripped away and is now at the bottom of the crankcase, waiting to be transferred back to the oil tank. Sy, with burping you move away useless oil and replace it with oil at places that matter. > Except after an oil/filter change l do not burp my engine at all. I > know the oil level in the tank when cold that corresponds to 'enough > oil'. This procedure leaves oil in the engine and hopefully will > result in less wear over it's life. Not burping the engine actually increases wear. And you risk a hydraulic lock some day, when a surplus of crankcase oil has seaped into a cylinder. This will destroy your engine in a split second when the starter cranks the engine. Who is that clown who told you not to burp your engine? Frans ________________________________ Message 6 _____________________________________ Time: 04:34:06 AM PST US From: "Sidsel & Svein Johnsen" Subject: SV: Europa-List: Re: burping the 912 The Rotax manual tells us to turn the engine prior to starting only with reference to verifying the oil level in the reservoir tank (i.e. with empty crankcase). The manual also explains how the turning brings the oil back to the tank: Compressed air is leaking past the piston rings into the crankcase, and this overpressure in the crankcase pushes the oil back to the tank. This leakage of compressed air past the piston rings will also blow away some oil deposited on the cylinder walls during the down stroke, while the scraping of the rings removes some oil both in the down and up stroke. I doubt that there is any meaningful buildup of oil pressure (i.e. enough for lubrication) during this short-lasting and slow hand cranking. If there were some pressure with resulting oil flow, it would mean that oil is flowing back into the very crankcase that we try to drain, wouldn't it? I have attended the Rotax maintenance course first in Denmark, later in Norway. The very experienced service agent for Scandinavia both times recommended doing this turning-for-oil-level-check immediately after stopping the engine - not prior to starting it. The reason is that the engine is easier to turn when warm, and the oil has lower viscosity - it therefore flows easier back to the tank. This difference is noticeable on cold winter days. Risk of oil lock in a cylinder with our type of engine/lubricating system: I do not know. A different matter altogether is whether to turn the engine after it has been preserved with special oil, e.g. for winter storage. Turning should then NOT be done, as it will scrape/blow preservation oil off the cylinder walls. Regards, Svein LN-SKJ ________________________________ Message 7 _____________________________________ Time: 05:13:54 AM PST US Subject: Europa-List: Re: Throttle Cables From: "europapa" Hello Bob, due to my basic English I am not sure what you want to tell me. I too think that the cables always should be pulled by the springs. In my case the were pushed caused by to high friction. Thats why I replaced them. But maybe I got something wrong. Regards Juergen Read this topic online here: http://forums.matronics.com/viewtopic.php?p=365443#365443 ________________________________ Message 8 _____________________________________ Time: 06:24:13 AM PST US From: Bob Harrison Subject: RE: Europa-List: Re: Throttle Cables Hi! Juergen Your first e-mail on the subject seemed to indicate that before you had the plane the cables were PUSHED by the throttle then you changed it.# Regards Bob H G-PTAG -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] On Behalf Of europapa Sent: 02 February 2012 13:07 Subject: Europa-List: Re: Throttle Cables Hello Bob, due to my basic English I am not sure what you want to tell me. I too think that the cables always should be pulled by the springs. In my case the were pushed caused by to high friction. Thats why I replaced them. But maybe I got something wrong. Regards Juergen Read this topic online here: http://forums.matronics.com/viewtopic.php?p=365443#365443 ________________________________ Message 9 _____________________________________ Time: 08:15:29 AM PST US From: "uvtreith" Subject: AW: Europa-List: Smart engine istalled in a EUROPA Hi Fred and others who are interested in the adventure, getting another engine into the Europa Some info to the time schedule September 2006 the plane was built up and the wing load test was done. In October 2006 I got the plane to Europa Aircraft CZ for engine installation (was still installed on the Mock-Up) painting and making the Interior (with my supplied blue-violet cow skin). They also changed and repaired things which I had not made proper enough. I called that "fine tuning and trimming". October 2007 I was taking the plane back to Germany. During 2008 we made the Electricity, Instrumentation, Panel Installation etc. In May 2009 we had a Europa Fly-In on my airfield and I discussed the engine installation with some Europa owners. After that I decided to proof the strengths of the system by making an engine/fuselage load test. I made a load bridge for the cement sacks and the four legs of this bridge were positioned on the engine fixing points. Unfortunately one of the 4 legs was not fully located so that in fact only three legs were able to carry the load. We put 19 sacks with total 475 kg, the bridge weight of 36 kg plus the engine weight itself, which I forgot to add. Than suddenly it made a short movement and the engine tray was bended, where the double load was. AND than I trapped into Murphy's Law: 1. Mistake: I removed the engine 2. Mistake: When I placed the engine on the ground, I forgot to remove the oil temperature sensor from the carbon fibre oil pan 3. Mistake: I repaired the engine mounting frame outside of the plane. During 2010 I had to get my mother into my house, as she could not live on her own anymore. I sold her house and had to get most of her house content into my house or to the Maltese organisation. In spring 2011 we installed the engine mounting frame and the engine. By the first test run we noticed that oil was coming out of the oil pan thermo connector. So I had to repair the oil pan first. When we were happy with the engine runs, we "tried" to get the cowl on and found out, that the engine mounting frame was still slightly bended and the spinner was scratching the upper cowl. Then Murphy decided to let me go my own way: I started to think and remembered a friend, who had got a welder licence for aeroplanes. He had built up a Steen Skybolt Bi-Plane only by drawings and he was a very long time the Vice President of the OUV (German Amateur Build). I bought a mobile hydraulic engine hoist (like car repair shops have), we removed the rear fixing points of frame and engine, aligned the engine into the proper position and he welded direct on the plain the mounting frame correctly. He is a man with a lot of experience. All this was taking 4 hours and I paid only 150 EURO. So in fact, I could be airborne since July 2009. But one positive thing was: There were and are now cracks and deformations between the firewall/fuselage and the engine mounting frame. The Europa is constructed and built so strong you can trust on. Nice plane and I am very hot to burn holes in the sky now. All the Best, Bruno _____ Von: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] Im Auftrag von Fred Klein Gesendet: Mittwoch, 1. Februar 2012 18:44 An: europa-list@matronics.com Betreff: Re: Europa-List: Smart engine istalled in a EUROPA On Jan 31, 2012, at 7:48 AM, uvtreith wrote: Sorry for this delay but it takes some time to make the required info ready for you. Please see attached pictures. If you need more info, please feel free and contact me via the forum or direct. Bruno, Thank you for posting these photos and information on your engine installation...fascinating. As a fellow alternative engine enthusiast, I envy you for the technical support you've received from Mercedes and Otto Funk. I may be mistaken, but for some reason I seem to recall that your plane was complete back in 2006...I'm curious if you would be willing to share a timeline of significant dates of your development test work between then and now...(?). Fred ________________________________ Message 10 ____________________________________ Time: 08:19:17 AM PST US Subject: Europa-List: Re: Throttle Cables From: "europapa" yes Bob, they have been pushed due to a suboptimal routing and the high inner friction. Now with the old, cold grease the possible, dangerous potential became obvious. Juergen Read this topic online here: http://forums.matronics.com/viewtopic.php?p=365448#365448 ________________________________ Message 11 ____________________________________ Time: 08:58:56 AM PST US Subject: Europa-List: Pilot Handbook for XS tri gear From: "skanderup" Hi Everyone, I have enjoyed a lot of your conversations and picked a lot of good advise from the enormous amount of knowledge on this blog. Thanks for that. I have made my way through my build and I am now getting close to the stage where I need to spend time on my pilot handbook. I have read the standard .pdf on Europa's web page. It does not comply with Danish requirements fully, so I will have to do a lot of editing. I was wondering if anyone had taken the time to type up the manual - and if I possibly could have a copy? I guess this is one of those which can take forever... Any assistance would be much appreciated. All the best Allan Skanderup Nielsen, allan_skanderup@hotmail.com XS Tri gear, kit no. 622, Denmark. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=365451#365451 ________________________________ Message 12 ____________________________________ Time: 09:53:25 AM PST US From: "G-IANI" Subject: RE: Europa-List: Pilot Handbook for XS tri gear Allan As you note the POH is available on the Europa web site as a PDF. This can be converted back to a Word document with suitable software such as PDF Converter Pro (their may be a small loss of format information). So there is no need to retype it If you do not facilities to do this let me know and I will convert it for you. Ian Rickard G-IANI XS Trigear, 300hours Europa Club Mods Specialist e-mail g-iani@ntlworld.com ________________________________ Message 13 ____________________________________ Time: 09:53:25 AM PST US From: Fred Klein Subject: Re: AW: Europa-List: Smart engine istalled in a EUROPA On Feb 2, 2012, at 8:06 AM, uvtreith wrote: > But one positive thing was: There were and are now cracks and > deformations between the firewall/fuselage and the engine mounting > frame. The Europa is constructed and built so strong you can trust on. > Nice plane and I am very hot to burn holes in the sky now. Bruno, I salute your perseverence...sorry about that Murphy guy...he's always lurking in the shadows. If I understand you correctly, the bending of your engine mounting frame during your load test was due to total load being distributed asymmetrically on only 3 of the 4 engine mounting points. I'm wondering if there is a typo in your sentence above where you write: >> There were and are now cracks and deformations between the firewall/ >> fuselage and the engine mounting frame. Did you mean to write that there "are NO cracks and deformations"?...please explain. Thanks, Fred ________________________________ Message 14 ____________________________________ Time: 10:13:07 AM PST US Subject: Re: Europa-List: Pilot Handbook for XS tri gear From: Rowland Carson On 2 Feb 2012, at 16:53, skanderup wrote: > I have made my way through my build and I am now getting close to the stage where I need to spend time on my pilot handbook. > > I have read the standard .pdf on Europa's web page. It does not comply with Danish requirements fully, so I will have to do a lot of editing. I was wondering if anyone had taken the time to type up the manual - and if I possibly could have a copy? I guess this is one of those which can take forever... > > Any assistance would be much appreciated. Allan - don't know what application you use for reading PDFs, but I find this works on the Mac with Preview (I try not to use Adobe Reader now as it is very greedy): >From the "Edit" menu, choose "Select all", then "Copy"; open a text-editor or word-processor application; from its "Edit" menu choose "Paste". That gives me all the existing text ready for editing. in friendship Rowland | Rowland Carson ... that's Rowland with a 'w' ... | http://www.rowlandcarson.org.uk | Skype, Twitter: rowland_carson Facebook: Rowland Carson | pictures: http://picasaweb.google.com/rowlandcarson ________________________________ Message 15 ____________________________________ Time: 01:29:51 PM PST US From: "uvtreith" Subject: AW: AW: Europa-List: Smart engine istalled in a EUROPA Fred, That is correct. The distributed load was only on 3 engine mounting points instead of 4. Oh, I missed an no. There were and are NO cracks and deformations .... Cheers, Bruno _____ Von: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] Im Auftrag von Fred Klein Gesendet: Donnerstag, 2. Februar 2012 18:46 An: europa-list@matronics.com Betreff: Re: AW: Europa-List: Smart engine istalled in a EUROPA On Feb 2, 2012, at 8:06 AM, uvtreith wrote: But one positive thing was: There were and are now cracks and deformations between the firewall/fuselage and the engine mounting frame. The Europa is constructed and built so strong you can trust on. Nice plane and I am very hot to burn holes in the sky now. Bruno, I salute your perseverence...sorry about that Murphy guy...he's always lurking in the shadows. If I understand you correctly, the bending of your engine mounting frame during your load test was due to total load being distributed asymmetrically on only 3 of the 4 engine mounting points. I'm wondering if there is a typo in your sentence above where you write: There were and are now cracks and deformations between the firewall/fuselage and the engine mounting frame. Did you mean to write that there "are NO cracks and deformations"?...please explain. Thanks, Fred ________________________________ Message 16 ____________________________________ Time: 02:45:26 PM PST US From: Frans Veldman Subject: Re: SV: Europa-List: Re: burping the 912 On 02/02/2012 01:28 PM, Sidsel & Svein Johnsen wrote: > This leakage of compressed air past the piston rings will also blow away > some oil deposited on the cylinder walls during the down stroke, "Blow away the oil"??? The idea here is not to turn the prop like a mad man, but to slowly rotate the prop, and preferably wait at each compression point to let the air slowly leak out. There is no blowing here, just gentle movement. > I doubt that there is any meaningful buildup of oil pressure (i.e. enough You can actually achieve full operational oil pressure with hand cranking. Of course the oil will soon leak past the bearings so the pressure won't hold for long, but at least the bearings get lubricated. If you don't believe it, get an assistant to rotate the prop, switch on the engine instruments (NOT the ignition!) and observe the oil pressure. The engine needs to be cold for the pressure to build up, but this is of course what we are discussing, to burp a cold engine. > If there > were some pressure with resulting oil flow, it would mean that oil is > flowing back into the very crankcase that we try to drain, wouldn't it? Yes, but this amount is much less than the oil that dripped into the crankcase during the long time the engine was switched off. The bearings have become dry and all the oil is at the bottom of the engine. Sure you add some new oil to this, but the surpluss will be removed and the bearings receive a fresh load of oil. There is another thing you need to consider: oil will slowly leak back from the oil tank into the engine, if the level in the oil tank is higher than in the engine (which is usually the case). The amount depends on various factors but it will build up over time. It is even possible (and has happened) that the oil in the engine seeps into the cylinders. Since oil is not compressible it will wreck the engine during the compression stroke. This reason alone is worth the trouble to hand crank the engine just before starting, so you can feel in time if the engine "locks" due to oil in a cylinder. > I have attended the Rotax maintenance course first in Denmark, later in > Norway. The very experienced service agent for Scandinavia both times > recommended doing this turning-for-oil-level-check immediately after > stopping the engine - not prior to starting it. So instead off scraping away the oil or "blowing it away" just before starting, it is now done just after switching it off (which is still before the subsequent startup). Either way, the procedure is carried out somewhere in the time frame between the shut down and the next startup. Even if I follow the reasoning that burping the engine removes some oil, I still fail to see why removing this oil immediately after shut down would be better than just before the next startup. I would rather leave it there as long as possible. Bad reasoning sometimes spread very fast. I wonder whether anyone has conducted some serious research on this? Who came up with this reasoning? > The reason is that the > engine is easier to turn when warm, Well, if this is the most important consideration I will agree with it. But for me, I happily sacrifice some ease in favor of the longevity of my engine. > Risk of oil lock in a cylinder with our type of engine/lubricating system: > I do not know. See above. It is a realistic risk. I had a leaking return valve in my turbo oil return line, and in a few weeks of time my turbo was filled with oil. The same can happen with the crankcase (and subsequently the cylinders). All in all, burping the engine removes some oil, regardless whether this is done immediately after shut down or just before start up, but doing it just before startup has the benefit that the bearings are relubricated and a potential hydraulic lock is detected in time. Frans ________________________________ Message 17 ____________________________________ Time: 03:48:13 PM PST US Subject: Re: SV: Europa-List: Re: burping the 912 From: Robert Borger Frans, I agree with your assessment. Except that burping right after shutdown does any good. Right after shutdown, there's no oil in the crankcase to return to the reservoir. While operating, the engine crankcase has been continuously pressurized returning any oil to the reservoir. You do the "burp" on a cold engine prior to the start in order to return any oil accumulated in the crankcase (or cylinders) back to the reservoir so the quantity may be properly checked. It also serves to provide some pre-lub to the bearings and oil galleries. The oil in the crankcase will have come from some residual drain down from the engine, but mostly from the siphoning from the reservoir back into the crankcase. This si because in our aircraft the reservoir level is almost always above the crankcase. My engine has been down for almost a year but I still "burp" the engine every time I go to the hanger to work. And every time it takes a fair number of blades to push about a half a quart of the oil back into the reservoir. It's down about half a quart prior to burp and is full after the burp. This also pumps fresh oil into the galleries and bearings keeping things coated with fresh oil. And probably adds to that half quart in the crankcase as it drains down between visits. Blue skies & tailwinds, Bob Borger Europa XS Tri, Rotax 914, Airmaster C/S Prop. Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP 3705 Lynchburg Dr. Corinth, TX 76208-5331 Cel: 817-992-1117 rlborger@mac.com On Feb 2, 2012, at 4:34 PM, Frans Veldman wrote: > > On 02/02/2012 01:28 PM, Sidsel & Svein Johnsen wrote: > >> This leakage of compressed air past the piston rings will also blow away >> some oil deposited on the cylinder walls during the down stroke, > > "Blow away the oil"??? The idea here is not to turn the prop like a mad > man, but to slowly rotate the prop, and preferably wait at each > compression point to let the air slowly leak out. There is no blowing > here, just gentle movement. > >> I doubt that there is any meaningful buildup of oil pressure (i.e. enough > > You can actually achieve full operational oil pressure with hand > cranking. Of course the oil will soon leak past the bearings so the > pressure won't hold for long, but at least the bearings get lubricated. > If you don't believe it, get an assistant to rotate the prop, switch on > the engine instruments (NOT the ignition!) and observe the oil pressure. > The engine needs to be cold for the pressure to build up, but this is of > course what we are discussing, to burp a cold engine. > >> If there >> were some pressure with resulting oil flow, it would mean that oil is >> flowing back into the very crankcase that we try to drain, wouldn't it? > > Yes, but this amount is much less than the oil that dripped into the > crankcase during the long time the engine was switched off. The bearings > have become dry and all the oil is at the bottom of the engine. Sure you > add some new oil to this, but the surpluss will be removed and the > bearings receive a fresh load of oil. > > There is another thing you need to consider: oil will slowly leak back > from the oil tank into the engine, if the level in the oil tank is > higher than in the engine (which is usually the case). The amount > depends on various factors but it will build up over time. > It is even possible (and has happened) that the oil in the engine seeps > into the cylinders. Since oil is not compressible it will wreck the > engine during the compression stroke. This reason alone is worth the > trouble to hand crank the engine just before starting, so you can feel > in time if the engine "locks" due to oil in a cylinder. > >> I have attended the Rotax maintenance course first in Denmark, later in >> Norway. The very experienced service agent for Scandinavia both times >> recommended doing this turning-for-oil-level-check immediately after >> stopping the engine - not prior to starting it. > > So instead off scraping away the oil or "blowing it away" just before > starting, it is now done just after switching it off (which is still > before the subsequent startup). Either way, the procedure is carried out > somewhere in the time frame between the shut down and the next startup. > Even if I follow the reasoning that burping the engine removes some oil, > I still fail to see why removing this oil immediately after shut down > would be better than just before the next startup. I would rather leave > it there as long as possible. > > Bad reasoning sometimes spread very fast. I wonder whether anyone has > conducted some serious research on this? Who came up with this reasoning? > >> The reason is that the >> engine is easier to turn when warm, > > Well, if this is the most important consideration I will agree with it. > But for me, I happily sacrifice some ease in favor of the longevity of > my engine. > >> Risk of oil lock in a cylinder with our type of engine/lubricating system: >> I do not know. > > See above. It is a realistic risk. I had a leaking return valve in my > turbo oil return line, and in a few weeks of time my turbo was filled > with oil. The same can happen with the crankcase (and subsequently the > cylinders). > > All in all, burping the engine removes some oil, regardless whether this > is done immediately after shut down or just before start up, but doing > it just before startup has the benefit that the bearings are > relubricated and a potential hydraulic lock is detected in time. > > Frans > > > > > ________________________________ Message 18 ____________________________________ Time: 04:35:17 PM PST US From: GRAHAM SINGLETON Subject: Re: SV: Europa-List: Re: burping the 912 Frans=0Athat is sufficiant reason for me to think that doing it before star t up makes good sense. Thanks for your patience to reason it all out!=0AGra ham=0A=0A=0A________________________________=0A From: Frans Veldman =0ATo: europa-list@matronics.com =0ASent: Thursday, 2 Febr uary 2012, 22:34=0ASubject: Re: SV: Europa-List: Re: burping the 912=0A =0A =0A=0AAll in all, burping the engine removes some oil, regardless whether t his=0Ais done immediately after shut down or just before start up, but doin g=0Ait just before startup has the benefit that the bearings are=0Arelubric ated and a potential hydraulic lock is detected in time.=0A=0AFrans ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message europa-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Europa-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/europa-list Browse Digests http://www.matronics.com/digest/europa-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.