---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Fri 03/06/09: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:55 AM - Re: Oil Filter (Craig Payne) 2. 04:18 AM - Re: Nanchang Generator Problem (Donna or Steve Hanshew) 3. 12:36 PM - Test only for funcionality of new email address (DAVID STROUD) 4. 03:34 PM - Re: Re: Oil filter (Yak Pilot) 5. 04:13 PM - Re: Re: Oil filter (talew@bellsouth.net) 6. 04:20 PM - oil (talew@bellsouth.net) 7. 05:27 PM - CJ Tow Bar (Craig Winkelmann) ________________________________ Message 1 _____________________________________ Time: 03:55:05 AM PST US From: "Craig Payne" Subject: Yak-List: Re: Oil Filter Oh well, here we go again. Oil filtration systems on the CJ can be, and have been installed several different ways. Just because a particular filter element is used, does NOT define the layout of the installation. IMHO, in cold weather operations one proven failure mode is the built-in Oil Cooler Bypass Valve. Often this valve becomes gummed up with carbon sludge and fails to function properly, allowing pressures to build "upstream". Excess pressure has been known to rupture oil coolers in both CJ's and Yaks. Without a properly functioning Filter Bypass built into the filter base, the element could rupture as well. It takes BOTH bypass valves working to provide a path for high pressure oil. Another discussion could be had about WHAT should be done in cold weather BEFORE the start switch is pushed and HOW the engine should be warmed up. I have started my CJ in below freezing weather, with the oil filter installed, and have seen no failures. However, I did see the oil pressure go to zero, in flight, because my shutters were jammed open in cold temps. Another question is WHAT the effect of cold starting has on long-term life of the engine. Craig Payne cpayne@joimail.com ________________________________ Message 2 _____________________________________ Time: 04:18:16 AM PST US From: "Donna or Steve Hanshew" Subject: Re: Yak-List: Nanchang Generator Problem Do it the same. ----- Original Message ----- From: Jay McIntyre To: yak list Sent: Thursday, March 05, 2009 2:55 PM Subject: Yak-List: Nanchang Generator Problem OK... if flashing the field is the answer, how does one go about it on the Nanchang? I have done a conventional western generator/regualtor before by following the procedure in the A&P manuals but would like to know how to do the Nanchang! Cheers, Jay ________________________________ Message 3 _____________________________________ Time: 12:36:10 PM PST US From: "DAVID STROUD" Subject: Yak-List: Test only for funcionality of new email address new email address is dstroud@xplornet.com David Stroud Ottawa, Canada Christavia C-FDWS Fairchild 51 replica under construction C-FYXV ________________________________ Message 4 _____________________________________ Time: 03:34:13 PM PST US From: Yak Pilot Subject: Re: Yak-List: Re: Oil filter Keith, you said:- "I suspect a combination of the small filter size and 1 0 micron =0Apaper as well as the small by-pass led to the failure." =0A=0AO k.- I am sure that these were contributing factors, but hey... are you sa ying =0Athat you do not think that the temperature and the viscosity of the oil had =0Aanything to do with this?- =0A=0AThe engine block in your air craft was dead cold.- Even if the sump and oil =0Atank came up to temp in two hours, (which I have to wonder about) you have =0Ato realize that the oil in that oil cooler was colder than ... well... =0Areal cold (and so was the majority of the rest of a rather large motor).- =0A=0AI suspect your oil filter actually failed from an extreme overpressure due to =0Acold and thick oil.- We're talking about a gear driven pump design here!- =0A =0AI agree totally that the filter in your aircraft failed first, and that proves it was =0Athe weak link in the chain.- But I also remember seeing an M-14 blow the =0Aoil cooler apart like a freaking hand grenade when the whole engine was =0Anot pre-heated and there was a thick slug of cold oil i n the oil cooler.- =0A=0AI have flown engines with a tank pre-heater, a s ump pre-heater and an oil =0Afilter by-pass valve that is thermostat contro lled and with all that, I have =0ANEVER seen those-engines ready to taxi in that kind of temperature in two =0Aminutes... even after having it left the electric heaters on all night. =0A=0AStop and think... some of your oil was pre-heated.- When that oil hit your oil =0Atemp sensor, of course it will "look about right", but the engine itself is =0Aanything BUT warmed u p in two minutes!- =0A=0AThe original Russian design used an oil dilution system.- No one really likes that=0Asystem, but if operated properly it totally avoids failures of this nature.- I am =0Anot recommending that we use it, but if we decide to go to something else, we are =0Amoving into th e realm of experimental design.- Your new filter may indeed be STC'ed, =0Abut my bet is that you have simply moved the first weak point (filter) t o a NEW weak=0Apoint.. such as the oil cooler, or a hose.. or .... whatever . =0A=0AI am not saying this to disagree about your selection of a good oil filter, far =0Afrom it.- What I am saying is that I do not know a radial engine on the planet that =0Ais ready to taxi in two minutes after a 25 de gree Fahrenheit start-up without =0Aa complete engine pre-heat prior to sta rt.- =0A=0AJust my 2 cents, but something to at least think about. =0A=0A Mark Bitterlich=0A-=0A-=0A=0A=0A=0A=0A=0A______________________________ __=0AFrom: keithmckinley =0ATo: yak-list@matron ics.com=0ASent: Thursday, March 5, 2009 7:57:29 PM=0ASubject: Yak-List: Re: inley@townisp.com>=0A=0AFor what it's worth I purchased a CJ- with a syst em, if not Craig's, is exactly the same right down to the Marion Hyd Filter .=0A=0ARecently the system suffered a catastrophic failure on the ground. =0A=0AI use Phillips 25-60W radial engine oil and my aircraft had been in a n unheated hangar during a cold night. It was about 25 degrees the morning I was to fly. Prior to engine start, I had my sump and tank heater on for t wo hours. I did not have a strip heater on my oil cooler. Prior to engine s tart the oil temp indicated just above 10C=0A=0AAfter engine start, pressur e and temp were normal for the conditions and the engine was at idle for 2- 3 minutes before I added power to taxi.=0A=0AAs I added power the system fa iled. The oil filter actually blew up like a balloon, but it was the thread ed shaft ( for the filter) on the housing that suffered a shear failure.=0A =0AI do know that even cold hyd fluid has a lot less viscosity than my engi ne oil. I also know that the by-pass in the housing was insufficient in my case.=0AIt's very small, maybe 1/8 or 3/16 in diameter. Also, Without going back to my logs I was about 25 hours from the last oil change. I suspect a combination of the small filter size and 10 micron paper as well as the sm all by-pass led to the failure.=0A=0AIt's up to you to evaluate each system for what it was designed to do, what you plan to do with it, and how your operational environment will affect it=0A=0AI've installed the ADC spin on system for radial engines. I like the fact that it uses aviation grade oil filters, it is STC'd, it has a very large by-pass, and can accept a chip de tector system.=0A=0ATo each his own.=0A=0AKeith=0A=0A--------=0AKeith McKin ley=0A700 HS=0AKFIT=0A=0A=0A=0A=0ARead this topic online here:=0A=0Ahttp:// forums.matronics.com/viewtopic.php?p=233412#233412=0A=0A=0A=0A=0A=0A=0A ============ ________________________________ Message 5 _____________________________________ Time: 04:13:29 PM PST US From: talew@bellsouth.net Subject: Re: Yak-List: Re: Oil filter ________________________________ Message 6 _____________________________________ Time: 04:20:51 PM PST US From: talew@bellsouth.net Subject: Yak-List: oil ________________________________ Message 7 _____________________________________ Time: 05:27:45 PM PST US Subject: Yak-List: CJ Tow Bar From: "Craig Winkelmann" What are you guys using for a tow bar for the CJ to move the aircraft in and out of a hangar? Craig W Read this topic online here: http://forums.matronics.com/viewtopic.php?p=233540#233540 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message yak-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Yak-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/yak-list Browse Digests http://www.matronics.com/digest/yak-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.