---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Sat 02/17/18: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 11:34 AM - Re: Oil - where can it go? (Looigi) 2. 12:26 PM - Re: Re: Oil - where can it go? (John B) 3. 12:31 PM - Re: Re: Oil - where can it go? (Ernest Martinez) 4. 01:49 PM - Re: Re: Oil - where can it go? (Walter Lannon) 5. 08:15 PM - Engine stumble in flight (Looigi) 6. 08:47 PM - Re: Engine stumble in flight (John B) 7. 09:10 PM - Re: Engine stumble in flight (Roger Kemp) 8. 09:33 PM - Re: Engine stumble in flight (Looigi) 9. 09:49 PM - Re: Re: Engine stumble in flight (John B) 10. 10:27 PM - Re: Re: Engine stumble in flight (Gary Gabbard) ________________________________ Message 1 _____________________________________ Time: 11:34:10 AM PST US Subject: Yak-List: Re: Oil - where can it go? From: "Looigi" Hi Andrew, You have made me feel a lot better about the 1.5l/h oil consumption on our Yak-52. I have also fixed the odd oil leak and poked and prodded the engine, but the seemingly high oil consumption is still there. I have come to the conclusion that 'it is what it is' and as long as the consumption rate doesn't change I am going to live with it. Chris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=478049#478049 ________________________________ Message 2 _____________________________________ Time: 12:26:17 PM PST US From: John B Subject: Re: Yak-List: Re: Oil - where can it go? Oil, where does it go? Fellow Yak operators: Oil consumption has a great deal to do with what one is doing with the airplane. When one does aerobatics, oil gets vented. We cannot measure this until after we land, and get the airplane into the same position/condition as when the oil was checked prior to the flight. Some considerations: Was the airplane level when the oil was checked? The dipstick was inserted the same way each time? Was the dipstick removed, wiped off, and then reinserted? However this is done, accuracy depends on doing it consistently. Also, how much oil dripped out of the exhaust manifolds? How much drained out of the intake? How much is left in the sump? The weeping of the occasional seal or gasket won't generally cause a measurable amount of oil consumption. It takes very little oil to really make a mess of a firewall or the belly of an airplane. On a recent cross-country flight, with four landings, I burned ZERO measurable amount of oil. None. Not a drop, in probably 7 hours of flying time. Aerobatic flight generally requires the occasional quart of oil to be added between changes. This engine is quite dry. I've flown Lycoming and Continental engines that "consumed" more, burned or vented... On Sat, Feb 17, 2018 at 1:33 PM, Looigi wrote: > > Hi Andrew, > > You have made me feel a lot better about the 1.5l/h oil consumption on our > Yak-52. > > I have also fixed the odd oil leak and poked and prodded the engine, but > the seemingly high oil consumption is still there. I have come to the > conclusion that 'it is what it is' and as long as the consumption rate > doesn't change I am going to live with it. > > Chris > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=478049#478049 > > ________________________________ Message 3 _____________________________________ Time: 12:31:34 PM PST US From: Ernest Martinez Subject: Re: Yak-List: Re: Oil - where can it go? Somebody added oil when you werent looking.. On Sat, Feb 17, 2018 at 3:24 PM, John B wrote: > Oil, where does it go? > > Fellow Yak operators: Oil consumption has a great deal to do with what > one is doing with the airplane. When one does aerobatics, oil gets > vented. We cannot measure this until after we land, and get the airplane > into the same position/condition as when the oil was checked prior to the > flight. > > Some considerations: Was the airplane level when the oil was checked? > The dipstick was inserted the same way each time? Was the dipstick > removed, wiped off, and then reinserted? However this is done, accuracy > depends on doing it consistently. Also, how much oil dripped out of the > exhaust manifolds? How much drained out of the intake? How much is left > in the sump? The weeping of the occasional seal or gasket won't generally > cause a measurable amount of oil consumption. It takes very little oil to > really make a mess of a firewall or the belly of an airplane. > > On a recent cross-country flight, with four landings, I burned ZERO > measurable amount of oil. None. Not a drop, in probably 7 hours of flying > time. > Aerobatic flight generally requires the occasional quart of oil to be > added between changes. This engine is quite dry. I've flown Lycoming and > Continental engines that "consumed" more, burned or vented... > > > On Sat, Feb 17, 2018 at 1:33 PM, Looigi wrote: > >> >> Hi Andrew, >> >> You have made me feel a lot better about the 1.5l/h oil consumption on >> our Yak-52. >> >> I have also fixed the odd oil leak and poked and prodded the engine, but >> the seemingly high oil consumption is still there. I have come to the >> conclusion that 'it is what it is' and as long as the consumption rate >> doesn't change I am going to live with it. >> >> Chris >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=478049#478049 >> >> >> >> >> >> >> =================================== >> List" rel="noreferrer" target="_blank">http://www.matronics.com/ >> Navigator?Yak-List >> =================================== >> FORUMS - >> eferrer" target="_blank">http://forums.matronics.com >> =================================== >> WIKI - >> errer" target="_blank">http://wiki.matronics.com >> =================================== >> b Site - >> -Matt Dralle, List Admin. >> rel="noreferrer" target="_blank">http://www.matronics.com/contribution >> =================================== >> >> >> >> > ________________________________ Message 4 _____________________________________ Time: 01:49:18 PM PST US From: "Walter Lannon" Subject: Re: Yak-List: Re: Oil - where can it go? All valid considerations and, without a doubt, accuracy depends on consiste ncy. You did mention =9Chow much is left in the sump=9D but not your scavenge run (time & RPM) prior to shut down nor the oil temp at time of m easurement. If you measure cold oil before start and hot oil after flight you might eve n =9Cmanufacture=9D some oil with a real tight engine. Cheers; Walt From: John B Sent: Saturday, February 17, 2018 12:24 PM Subject: Re: Yak-List: Re: Oil - where can it go? Oil, where does it go? Fellow Yak operators: Oil consumption has a great deal to do with what one is doing with the airplane. When one does aerobatics, oil gets vented. W e cannot measure this until after we land, and get the airplane into the sa me position/condition as when the oil was checked prior to the flight. Some considerations: Was the airplane level when the oil was checked? The dipstick was inserted the same way each time? Was the dipstick removed, w iped off, and then reinserted? However this is done, accuracy depends on d oing it consistently. Also, how much oil dripped out of the exhaust manifo lds? How much drained out of the intake? How much is left in the sump? T he weeping of the occasional seal or gasket won't generally cause a measura ble amount of oil consumption. It takes very little oil to really make a m ess of a firewall or the belly of an airplane. On a recent cross-country flight, with four landings, I burned ZERO measura ble amount of oil. None. Not a drop, in probably 7 hours of flying time. Aerobatic flight generally requires the occasional quart of oil to be added between changes. This engine is quite dry. I've flown Lycoming and Conti nental engines that "consumed" more, burned or vented... On Sat, Feb 17, 2018 at 1:33 PM, Looigi wrote: Hi Andrew, You have made me feel a lot better about the 1.5l/h oil consumption on ou r Yak-52. I have also fixed the odd oil leak and poked and prodded the engine, but the seemingly high oil consumption is still there. I have come to the conc lusion that 'it is what it is' and as long as the consumption rate doesn't change I am going to live with it. Chris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=478049#478049 ======================== =========== List" rel="noreferrer" target="_blank">http://www.matronics.com/Navig ator?Yak-List ======================== =========== FORUMS - eferrer" target="_blank">http://forums.matronics.com ======================== =========== WIKI - errer" target="_blank">http://wiki.matronics.com ======================== =========== b Site - -Matt Dralle, List Admin. rel="noreferrer" target="_blank">http://www.matronics.com/contributio n ======================== =========== --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 5 _____________________________________ Time: 08:15:30 PM PST US Subject: Yak-List: Engine stumble in flight From: "Looigi" I thought I would consult the Oracle before I rip into pulling things apart. One of the boys was flying the Yak today and he had a bit of a scare. He was cruising at about 800, 70% RPM and 700mm manifold pressure when the engine stopped running for 1-2 seconds. When the engine started again, there was lots of smoke out the exhaust. He continued with his flight, but when it happened again he returned and landed safely. I had him do a run up and the mag drops were fine, oil level was normal and the engine ran fine. I am suspecting a fuel issue? He said however that the engine had been harder to start (slow to turn over) on the last couple of flights - I am thinking that this is a seperate problem though. Any thoughts? Chris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=478062#478062 ________________________________ Message 6 _____________________________________ Time: 08:47:21 PM PST US From: John B Subject: Re: Yak-List: Engine stumble in flight 1-2 seconds is an eternity. An ignition problem would be quite possible. Does this aircraft have the auto plug conversion? On Sat, Feb 17, 2018 at 10:14 PM, Looigi wrote: > > I thought I would consult the Oracle before I rip into pulling things > apart. > > One of the boys was flying the Yak today and he had a bit of a scare. He > was cruising at about 800=99, 70% RPM and 700mm manifold pressure w hen the > engine stopped running for 1-2 seconds. When the engine started again, > there was lots of smoke out the exhaust. He continued with his flight, b ut > when it happened again he returned and landed safely. > > I had him do a run up and the mag drops were fine, oil level was normal > and the engine ran fine. I am suspecting a fuel issue? > > He said however that the engine had been harder to start (slow to turn > over) on the last couple of flights - I am thinking that this is a sepera te > problem though. > > Any thoughts? > Chris > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=478062#478062 > > =========== =========== =========== =========== =========== > > ________________________________ Message 7 _____________________________________ Time: 09:10:11 PM PST US From: Roger Kemp Subject: Re: Yak-List: Engine stumble in flight You have a bad mag coil. Happens about 15 to 20 minutes into the flight. Sudden engine stoppage with belching of unburned fuel in the supercharger as it misfires followed by normal engine for a short time. No mag drop on the ground. Think Doug Sapp still has some new mag coils in stock. Doc Sent from my iPad > On Feb 17, 2018, at 10:14 PM, Looigi wrote: > > > I thought I would consult the Oracle before I rip into pulling things apart. > > One of the boys was flying the Yak today and he had a bit of a scare. He was cruising at about 800, 70% RPM and 700mm manifold pressure when the engine stopped running for 1-2 seconds. When the engine started again, there was lots of smoke out the exhaust. He continued with his flight, but when it happened again he returned and landed safely. > > I had him do a run up and the mag drops were fine, oil level was normal and the engine ran fine. I am suspecting a fuel issue? > > He said however that the engine had been harder to start (slow to turn over) on the last couple of flights - I am thinking that this is a seperate problem though. > > Any thoughts? > Chris > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=478062#478062 > > > > > > > > > ________________________________ Message 8 _____________________________________ Time: 09:33:11 PM PST US Subject: Yak-List: Re: Engine stumble in flight From: "Looigi" Thanks Doc, I was wondering about that. Is there any way to test for this? I would like to confirm the fault, or at least which one it is. Or is it the tried and true shotgun method? No, Old school Russian plugs. Cheers Chris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=478069#478069 ________________________________ Message 9 _____________________________________ Time: 09:49:08 PM PST US From: John B Subject: Re: Yak-List: Re: Engine stumble in flight This may be a coil problem. But having one coil fail would cause the engine to lose a slight bit of power, as if one grounded one magneto. Replacing the coils on both mags would likely cure this problem. The auto plug conversion is worthwhile. The engine will run better. On Sat, Feb 17, 2018 at 11:32 PM, Looigi wrote: > > Thanks Doc, I was wondering about that. Is there any way to test for > this? I would like to confirm the fault, or at least which one it is. Or > is it the tried and true shotgun method? > > No, Old school Russian plugs. > > Cheers > Chris > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=478069#478069 > > ________________________________ Message 10 ____________________________________ Time: 10:27:50 PM PST US From: Gary Gabbard Subject: Re: Yak-List: Re: Engine stumble in flight Russian plugs work just fine. Check the mag point gap. I had that problem an d it turned out the gap had been set to wide. Make sure not to use 1000th of an inch. But make sure you use the metric gap specified in the manual. Tha t is a good place to start. It will occasionally miss and stumble. If a coi l goes it is usually dead. Good hunting. Gary. CJ. N22YK. LAS > On Feb 17, 2018, at 21:48, John B wrote: > > This may be a coil problem. But having one coil fail would cause the engi ne to lose a slight bit of power, as if one grounded one magneto. > Replacing the coils on both mags would likely cure this problem. > The auto plug conversion is worthwhile. The engine will run better. > >> On Sat, Feb 17, 2018 at 11:32 PM, Looigi wrote: >> >> Thanks Doc, I was wondering about that. Is there any way to test for thi s? I would like to confirm the fault, or at least which one it is. Or is i t the tried and true shotgun method? >> >> No, Old school Russian plugs. >> >> Cheers >> Chris >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=478069#478069 >> >> >> >> >> >> >> ========================= >> List" rel="noreferrer" target="_blank">http://www.matronics.com/Navig ator?Yak-List >> ========================= >> FORUMS - >> eferrer" target="_blank">http://forums.matronics.com >> ========================= >> WIKI - >> errer" target="_blank">http://wiki.matronics.com >> ========================= >> b Site - >> -Matt Dralle, List Admin. >> rel="noreferrer" target="_blank">http://www.matronics.com/contributio n >> ========================= >> >> >> > ========================== ========================== ========================== ========================== ========================== ========================== ========================== ============ ------------------------------------------------------------------------------------- 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.