---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Fri 06/22/18: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:26 AM - Re: CJ abeam, flap up/down (Richard Romaine) 2. 05:47 AM - CJ Mag Coils - Test data required (Harv) 3. 06:19 AM - Re: CJ Mag Coils - Test data required (George S. Coy) 4. 07:00 AM - Re: CJ Mag Coils - Test data required (Richard Goode) 5. 07:01 AM - Re: CJ Mag Coils - Test data required (Harv) 6. 07:30 AM - Re: Re: CJ Mag Coils - Test data required (George S. Coy) 7. 07:49 AM - Re: Re: CJ Mag Coils - Test data required (Justin Andersen) 8. 08:24 PM - Re: Re: Engine running rough at high power settings? (Roger Kemp) ________________________________ Message 1 _____________________________________ Time: 05:26:31 AM PST US From: Richard Romaine Subject: Re: Yak-List: CJ abeam, flap up/down Bear, No issues, discussion is one worth having, hope youdidn't eat all the crayo ns yet... =C2- // =C2- I agree with everyone that the CJ has the personality ofa chocolate lab, gi ve it 1500' and it will recover from any attitude/airspeedand want you to d o it again.=C2- Also agreethe CJ flap really is just a speed brake that b angs up or down, and energymanagement off the perch with the CJ flap up or down isn't particularly hard.=C2- My note is, that at least for my airfra me,it's not quite as forgiving with the flap down and it's worth planting t he seedfor other folks to think about it. =C2- I think the RPA abeam flap recommendation comes from communityexperience in other airframes where you needed the flap at approach speeds anddidn't wan t a long duration transition thru your turn or on final. =C2-Me personall y, I like having the extra margin withthe flap up when I'm close to the gro und still maneuvering.=C2- If I'm boneheaded enough to tickle the stallin the base to final that day, I'm probably boneheaded enough to pull rightba ck into a secondary stall that's more likely with the flap down.=C2- Flap up it would be a non-event, so I leave theflap alone until pretty much lin ed up, dump it, accept the pitch change andcontinue. =C2- While we have no "mandatory procedures" outsideFARs (or insurance company p references for having the gear down before landing),and it is strongly reco mmended to have a CJ experienced instructor, it's stillgood to critique "ac cepted practices" because sometimes there's roomfor improvement...where I c ame from our NATOPS was a living breathing collectionof test pilot/engineer ing and corporate knowledge, often learned from bad events,but hopefully pr evented by good ideas from the peanut gallery instead.=C2- =C2- Cheers, Rich ________________________________ Message 2 _____________________________________ Time: 05:47:14 AM PST US Subject: Yak-List: CJ Mag Coils - Test data required From: "Harv" Good morning all I was hoping someone here might have test data for new (or could measure up a new coil) 'in spec' CJ6 coils? I've been looking at my stumble issue on the Nanchang and removed both coils from the mags for bench testing both have been tested at ambient and then slow baked at 100deg for 60mins (I've no idea how hot they get in flight). The primary's (thick windings) were tested with a ohm meter setting of 200 and gave the following: Left mag at ambient = 00.5 ohm / Right mag at ambient = 00.5 ohm Left mag at 100deg = 00.8 ohm / Right mag at 100deg = 0.007 ohm The secondary side (thin windings with terminal sticking out of the core) were tested with an ohm meter setting of 20k and gave the following: Left mag at ambient = 9.32 ohm / Right mag at ambient = 9.16 ohm Left mag at 100deg = 11.96 ohm / Right mag at 100deg = 11.78 ohm I'm not sure this really identifies anything, resistance increasing with temp as expected, they both have fairly similar readings at both temp extremes. One thing I did notice, with the right mag coil connector where the cigarette bears onto it in situ looks to be quite chaffed and I sometimes struggled to get a reading off it as if the face isn't conducting too well and it's also a little looser than the one on the left mag. If the cigarette was to loose momentary connection at the coil in flight would this contribute to the stumble? (I can accept the resulting engine shake at the point of the stumble may re-establish the connection) Any ideas appreciated Cheers Harv Read this topic online here: http://forums.matronics.com/viewtopic.php?p=481085#481085 ________________________________ Message 3 _____________________________________ Time: 06:19:02 AM PST US From: "George S. Coy" Subject: RE: Yak-List: CJ Mag Coils - Test data required As I recall, the capacitor is buried in the middle of the coil assembly. The problem is usually the capacitor, not the windings breaking down. George Coy -----Original Message----- From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@matronics.com] On Behalf Of Harv Sent: Friday, June 22, 2018 8:47 AM Subject: Yak-List: CJ Mag Coils - Test data required Good morning all I was hoping someone here might have test data for new (or could measure up a new coil) 'in spec' CJ6 coils? I've been looking at my stumble issue on the Nanchang and removed both coils from the mags for bench testing both have been tested at ambient and then slow baked at 100deg for 60mins (I've no idea how hot they get in flight). The primary's (thick windings) were tested with a ohm meter setting of 200 and gave the following: Left mag at ambient = 00.5 ohm / Right mag at ambient = 00.5 ohm Left mag at 100deg = 00.8 ohm / Right mag at 100deg = 0.007 ohm The secondary side (thin windings with terminal sticking out of the core) were tested with an ohm meter setting of 20k and gave the following: Left mag at ambient = 9.32 ohm / Right mag at ambient = 9.16 ohm Left mag at 100deg = 11.96 ohm / Right mag at 100deg = 11.78 ohm I'm not sure this really identifies anything, resistance increasing with temp as expected, they both have fairly similar readings at both temp extremes. One thing I did notice, with the right mag coil connector where the cigarette bears onto it in situ looks to be quite chaffed and I sometimes struggled to get a reading off it as if the face isn't conducting too well and it's also a little looser than the one on the left mag. If the cigarette was to loose momentary connection at the coil in flight would this contribute to the stumble? (I can accept the resulting engine shake at the point of the stumble may re-establish the connection) Any ideas appreciated Cheers Harv Read this topic online here: http://forums.matronics.com/viewtopic.php?p=481085#481085 ________________________________ Message 4 _____________________________________ Time: 07:00:04 AM PST US From: "Richard Goode" Subject: RE: Yak-List: CJ Mag Coils - Test data required I agree with George - the problem is almost always the capacitor, and made worse with heat. That is why the coils typically begin to break down after 20 minutes or so flight when the heat of the engine has soaked through to the magneto. And of course having the capacitor inside the hot coil of wire only makes the situation worse. In England there are a number of companies working with old cars, many of which have magnetos, and we have been in touch with the best ones to get their advice. We decided on one particular company, who seemed very knowledgeable, and for two years now they have been making new coils for us. Of course they use the old coil former, but with better quality wiring. However more important is the fact that they use a small Panasonic capacitor which they bond to the outside of the coil, but in a way that makes no difference to its installation in the magneto. I should say that Aerometal, our partner in Hungary, have a high-temperature test cell with a special test magneto, in which the temperature can be elevated to well beyond any likely operating temperature. And we have found that these new coils are very satisfactory, as well as producing a much better spark and from much lower rpm than original coils. Richard Goode Aerobatics Rhodds Farm Lyonshall Hereford HR5 3LW Tel: +44 (0) 1544 340120 Fax: +44 (0) 1544 340129 www.russianaeros.com -----Original Message----- From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@matronics.com] On Behalf Of George S. Coy Sent: 22 June 2018 14:09 Subject: RE: Yak-List: CJ Mag Coils - Test data required As I recall, the capacitor is buried in the middle of the coil assembly. The problem is usually the capacitor, not the windings breaking down. George Coy -----Original Message----- From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@matronics.com] On Behalf Of Harv Sent: Friday, June 22, 2018 8:47 AM Subject: Yak-List: CJ Mag Coils - Test data required Good morning all I was hoping someone here might have test data for new (or could measure up a new coil) 'in spec' CJ6 coils? I've been looking at my stumble issue on the Nanchang and removed both coils from the mags for bench testing both have been tested at ambient and then slow baked at 100deg for 60mins (I've no idea how hot they get in flight). The primary's (thick windings) were tested with a ohm meter setting of 200 and gave the following: Left mag at ambient = 00.5 ohm / Right mag at ambient = 00.5 ohm Left mag at 100deg = 00.8 ohm / Right mag at 100deg = 0.007 ohm The secondary side (thin windings with terminal sticking out of the core) were tested with an ohm meter setting of 20k and gave the following: Left mag at ambient = 9.32 ohm / Right mag at ambient = 9.16 ohm Left mag at 100deg = 11.96 ohm / Right mag at 100deg = 11.78 ohm I'm not sure this really identifies anything, resistance increasing with temp as expected, they both have fairly similar readings at both temp extremes. One thing I did notice, with the right mag coil connector where the cigarette bears onto it in situ looks to be quite chaffed and I sometimes struggled to get a reading off it as if the face isn't conducting too well and it's also a little looser than the one on the left mag. If the cigarette was to loose momentary connection at the coil in flight would this contribute to the stumble? (I can accept the resulting engine shake at the point of the stumble may re-establish the connection) Any ideas appreciated Cheers Harv Read this topic online here: http://forums.matronics.com/viewtopic.php?p=481085#481085 ________________________________ Message 5 _____________________________________ Time: 07:01:09 AM PST US Subject: Yak-List: Re: CJ Mag Coils - Test data required From: "Harv" Thanks George So lets assume my capacitor breaks down during my oven test at 100 deg, would that translate into something visible on the ohm meter during my test (for example open circuit?) Tia Read this topic online here: http://forums.matronics.com/viewtopic.php?p=481092#481092 ________________________________ Message 6 _____________________________________ Time: 07:30:28 AM PST US From: "George S. Coy" Subject: RE: Yak-List: Re: CJ Mag Coils - Test data required No, but it would cause timing problems a weaker spark and be very hard on the points. George -----Original Message----- From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@matronics.com] On Behalf Of Harv Sent: Friday, June 22, 2018 10:01 AM Subject: Yak-List: Re: CJ Mag Coils - Test data required Thanks George So lets assume my capacitor breaks down during my oven test at 100 deg, would that translate into something visible on the ohm meter during my test (for example open circuit?) Tia Read this topic online here: http://forums.matronics.com/viewtopic.php?p=481092#481092 ________________________________ Message 7 _____________________________________ Time: 07:49:25 AM PST US From: Justin Andersen Subject: Re: Yak-List: Re: CJ Mag Coils - Test data required test > On Jun 22, 2018, at 8:30 AM, George S. Coy wrote: > > > No, but it would cause timing problems a weaker spark and be very hard on > the points. > George > > -----Original Message----- > From: owner-yak-list-server@matronics.com > [mailto:owner-yak-list-server@matronics.com] On Behalf Of Harv > Sent: Friday, June 22, 2018 10:01 AM > To: yak-list@matronics.com > Subject: Yak-List: Re: CJ Mag Coils - Test data required > > > Thanks George > > So lets assume my capacitor breaks down during my oven test at 100 deg, > would that translate into something visible on the ohm meter during my test > (for example open circuit?) > > Tia > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=481092#481092 > > > > > > > > > > > > > ________________________________ Message 8 _____________________________________ Time: 08:24:50 PM PST US From: Roger Kemp Subject: Re: Yak-List: Re: Engine running rough at high power settings? They are not your standard round seals. The problem usually is not the seal itself. It is usually with engine runs over time the collar nut loosens allowing the an air leak leaning out the affected cylinder. Each year during my annual I check them to make sure they are tight. Doc Sent from my iPad > On Jun 19, 2018, at 2:51 PM, apatton2 wrote: > > Re: induction system seals - are those o-ring type seals? I'm unfamiliar with them. Are the connections between the intake tubes and the case typically suspect, or is it the tubes and cylinders? > > -------- > Andrew Patton > Yak-50 > San Francisco, CA > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=481015#481015 > > > > > > > > > ------------------------------------------------------------------------------------- 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.