---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Tue 09/04/07: 31 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:04 AM - Re: Re: Ho Hum - Not! N8701 validates Zenith Design (Mike Allen) 2. 12:30 AM - Buying aluminium in Australia (Jugle) 3. 02:35 AM - Re: Buying aluminium in Australia (chris Sinfield) 4. 02:43 AM - Static ports (Dave Johnson) 5. 04:01 AM - Re: Static ports (DaveG601XL) 6. 04:04 AM - Re: Buying aluminium in Australia (Paul & Colleen Schelfhout) 7. 04:15 AM - Re: Re: Static ports (ZodieRocket) 8. 04:50 AM - Re: Buying aluminium in Australia (Peter W Johnson) 9. 06:45 AM - Re: Re: Ho Hum - Not! N8701 validates Zenith Design (burbby) 10. 07:00 AM - Backfire or Afterfire (george.mueller@aurora.org) 11. 07:46 AM - Re: Static ports () 12. 07:52 AM - Burger and a Chat (4rcsimmons@comcast.net (Rich Simmons)) 13. 07:53 AM - Re: Backfire or Afterfire (Jari Kaija (LapTop2)) 14. 07:55 AM - Re: Backfire or Afterfire (Jari Kaija (LapTop2)) 15. 09:04 AM - Re: Backfire or Afterfire (Kevin L. Rupert) 16. 09:40 AM - Re: Backfire or Afterfire (Robin Bellach) 17. 11:10 AM - Re: Backfire or Afterfire (Trainnut01@aol.com) 18. 12:08 PM - Re: Backfire or Afterfire (Crvsecretary@aol.com) 19. 12:41 PM - Re: Backfire or Afterfire (MacDonald Doug) 20. 12:48 PM - (no subject) (Kevin L. Rupert) 21. 01:06 PM - Re: Backfire or Afterfire (David Downey) 22. 01:07 PM - Re: Static ports (Terry Phillips) 23. 01:44 PM - Re: Static ports (Gig Giacona) 24. 01:49 PM - Re: (no subject) (Gig Giacona) 25. 03:26 PM - Re: Re: Static ports (Bill Naumuk) 26. 03:46 PM - Re: EA-81 Stratus Question -- Replacinig PSRU Bearings (Falcon) 27. 04:52 PM - Re: Backfire or Afterfire (n801bh@netzero.com) 28. 05:01 PM - Re: Backfire or Afterfire (JG) 29. 06:24 PM - Re: Re: Static ports (ZodieRocket) 30. 07:36 PM - New to list (Bob Sturgis) 31. 07:43 PM - Re: WW nose bowl disc (Bob Duns) ________________________________ Message 1 _____________________________________ Time: 12:04:31 AM PST US From: "Mike Allen" Subject: Re: Zenith-List: Re: Ho Hum - Not! N8701 validates Zenith Design Those are some great movies, Very effective, especially the landing. What part of the country are you in? Looks like a beautiful area. I plan to set up a VFR panel myself. Basic instruments, a radio and transponder. I'm in Southern California, so the transponder is a must. Thanks for the movies. I enjoyed them. You have built a great little airplane. I look forward to seeing your panel. Mike ----- Original Message ----- From: "Tommy Walker" Sent: Monday, September 03, 2007 7:19 PM Subject: Zenith-List: Re: Ho Hum - Not! N8701 validates Zenith Design > > Thanks Mike. > > Here are some links to pics and movies. We don't have a website with a > lot of pictures though. > > http://myweb.cableone.net/twalker/8701.jpg > > http://myweb.cableone.net/twalker/Taxi_by.mpg > > http://myweb.cableone.net/twalker/takeoff.mpg > > http://myweb.cableone.net/twalker/land1.mpg > > You may have to open the movies within Windows Media Player. > > I will upload a picture of the panel this week. Our panel is strictly > VFR. > > The interior is not complete. Hopefully soon. > > Tommy Walker in Alabama > Do Not Archive > > > Dirtbos wrote: >> Nice work guys. >> >> I think the plane looks very clean just the way it is. >> >> I would appreciate some close up photos of the panel and interior (if >> you can bring yourself to stop flying for awhile :D ). >> >> Do you have a bulders website? >> >> Mike > > > -------- > Tommy Walker > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=132596#132596 > > > ________________________________ Message 2 _____________________________________ Time: 12:30:32 AM PST US Subject: Zenith-List: Buying aluminium in Australia From: "Jugle" I've just got a quote for the sheets for my 601XL and the lead time on some thicknesses is 10-12 weeks. I'd like to try and get it all in one go to save on freight. Anyone out there recommend a supplier in Australia? I'm in East Gippsland, Victoria. Glenn. -------- Glenn Andressen 601XL- just started. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=132623#132623 ________________________________ Message 3 _____________________________________ Time: 02:35:36 AM PST US Subject: Zenith-List: Re: Buying aluminium in Australia From: "chris Sinfield" Hi Where did you order from? There are a few places on the east coast to buy from. Have you asked any of the other victorian builders where they got theirs? Give me an email off line at sinfield(a)zeta.org.au Chris Sinfield Zodiac Xl Jab 3300 Sydney. PS we welcome another Aussie Xl builder.. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=132628#132628 ________________________________ Message 4 _____________________________________ Time: 02:43:22 AM PST US From: "Dave Johnson" Subject: Zenith-List: Static ports I am planning on fitting the Dynon AOA Pitot head to the 601XL. This does not have a static port, so I will fit ports on either side of the fuselage. I understand the location is critical, so does anyone know where I should put them (practical suggetsions only - this is a family list!!). I have tried the obvious line of e-mailing Zenith, but no response at all. Dave Johnson CH601XL form a CZAW kit ________________________________ Message 5 _____________________________________ Time: 04:01:59 AM PST US Subject: Zenith-List: Re: Static ports From: "DaveG601XL" Dave, I asked this very question to ZAC at their Oshkosh booth this year. Nick said the location of a static port was not all that critical. The suggestion was on the fuselage side aft of the wing. Good luck, -------- David Gallagher 601 XL, tail and wings completed, fueslage almost done, engine next. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=132634#132634 ________________________________ Message 6 _____________________________________ Time: 04:04:31 AM PST US From: "Paul & Colleen Schelfhout" Subject: Re: Zenith-List: Buying aluminium in Australia G'day All, I found Airport Metals (Melbourne) to be fine - and they carried a full range for 6061 and had the best prices at the time (18 months ago) - Good luck. PS: I have their product listing in pdf format if that helps Paul Schelfhout CH701 - Cabin & fwd to go & really would like a turbo diesel up front, any thoughts welcome Do not archive ----- Original Message ----- From: "Jugle" Sent: Tuesday, September 04, 2007 3:29 PM Subject: Zenith-List: Buying aluminium in Australia > > I've just got a quote for the sheets for my 601XL and the lead time on > some thicknesses is 10-12 weeks. I'd like to try and get it all in one go > to save on freight. Anyone out there recommend a supplier in Australia? > I'm in East Gippsland, Victoria. > > Glenn. > > -------- > Glenn Andressen > 601XL- just started. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=132623#132623 > > > ________________________________ Message 7 _____________________________________ Time: 04:15:02 AM PST US From: "ZodieRocket" Subject: RE: Zenith-List: Re: Static ports Measurement I use in 150mm down from the upper longerons and 150 mm back from the firewall rivet line. Ensure to install two, one on either side of cabin. Mark Townsend Alma, Ontario Zodiac 601XL C-GOXL, CH701 just started www.ch601.org / www.ch701.com / www.Osprey2.com -----Original Message----- I asked this very question to ZAC at their Oshkosh booth this year. Nick said the location of a static port was not all that critical. The suggestion was on the fuselage side aft of the wing. Good luck, 9:31 AM ________________________________ Message 8 _____________________________________ Time: 04:50:01 AM PST US From: "Peter W Johnson" Subject: RE: Zenith-List: Buying aluminium in Australia Glenn, Try H-Aircraft Spares in Moorabbin:- H-Aircraft Spares P/L P.O. Box 503 Braeside 3195 Unit 8/63-65 Voltri Street, Mentone 3194. (opp the Moorabbin Airport) 03 9585 0941 tele 03 9585 0942 fax Cheers Peter Wonthaggi, Vic -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jugle Sent: Tuesday, 4 September 2007 5:29 PM Subject: Zenith-List: Buying aluminium in Australia I've just got a quote for the sheets for my 601XL and the lead time on some thicknesses is 10-12 weeks. I'd like to try and get it all in one go to save on freight. Anyone out there recommend a supplier in Australia? I'm in East Gippsland, Victoria. Glenn. -------- Glenn Andressen 601XL- just started. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=132623#132623 9:31 AM 9:31 AM ________________________________ Message 9 _____________________________________ Time: 06:45:45 AM PST US From: burbby Subject: Re: Zenith-List: Re: Ho Hum - Not! N8701 validates Zenith Design Nice looking 701 . Its probly my computer but i had to open the movies with Quick time. Nicely done and your plane looks great. Thanks Gary --------------------------------- Pinpoint customers who are looking for what you sell. ________________________________ Message 10 ____________________________________ Time: 07:00:20 AM PST US Subject: Zenith-List: Backfire or Afterfire From: george.mueller@aurora.org I am at the point of doing full power run-ups with my Zenith 701 with a rotax 912 UL 80hp installed with a Skyshops firewall forward kit. When I do a full power run up, I get a backfire (or afterfire maybe) after I turn the ignition key to "off". When I taxi around keeping the engine to around 2,000 rpm, this does not happen after shutdown, only after I do a full power run-up. Everything else seems normal as far as I can tell, the engine starts really well, seems to run smoothly, idles well. But after doing three full power run ups, I have had three backfires, all after turning off the ignition. Does anyone on the list have an idea about what might be causing this? George in Milwaukee 701 912UL ________________________________ Message 11 ____________________________________ Time: 07:46:00 AM PST US From: Subject: Re: Zenith-List: Static ports Why not install the Zenith supplied combo pitot and static source on the same or the other wing? The pitot could be valved to provide an alternate incase the Dynon pitot eats a bug or something. Seems easier than researching a good static point on the fuselage. Dred ---- Dave Johnson wrote: > I am planning on fitting the Dynon AOA Pitot head to the 601XL. This does not have a static port, so I will fit ports on either side of the fuselage. > > I understand the location is critical, so does anyone know where I should put them (practical suggetsions only - this is a family list!!). > > I have tried the obvious line of e-mailing Zenith, but no response at all. > > Dave Johnson > > CH601XL form a CZAW kit ________________________________ Message 12 ____________________________________ Time: 07:52:37 AM PST US From: 4rcsimmons@comcast.net (Rich Simmons) Subject: Zenith-List: Burger and a Chat Hey folks, I have a total of 7 people interested in visiting the Jabaru USA shop in Shelbyville, TN. It is right at the airport if They package the Firewall forward kits for the 601 and the 701. If anyone else is interested please let me know some time this week. After this week, I will set a time. Do not Archive -- Thanks, Rich Simmons 601XL Fuselage - Firewall stiffners ________________________________ Message 13 ____________________________________ Time: 07:53:22 AM PST US From: "Jari Kaija (LapTop2)" Subject: Re: Zenith-List: Backfire or Afterfire You are doing WHAT! Turning off ignition, while engine runs at maximum speed? What kind of test is this? Newer heard and I have quite a lott of experience with single piston aeroplanes, since I got my PPL license -96! Don't destroy your engine. Think a while! When you turn ignition off and engine have such kind of rpm. All gasoline/air mix will flow to muffler, because that mix didn't blow out in the cylinders. And muffler, when there is enough gas/air mix in a hot "steel botle", WILL catch fire!!!! ----- Original Message ----- From: george.mueller@aurora.org To: zenith-list@matronics.com Sent: Tuesday, September 04, 2007 4:58 PM Subject: Zenith-List: Backfire or Afterfire I am at the point of doing full power run-ups with my Zenith 701 with a rotax 912 UL 80hp installed with a Skyshops firewall forward kit. When I do a full power run up, I get a backfire (or afterfire maybe) after I turn the ignition key to "off". When I taxi around keeping the engine to around 2,000 rpm, this does not happen after shutdown, only after I do a full power run-up. Everything else seems normal as far as I can tell, the engine starts really well, seems to run smoothly, idles well. But after doing three full power run ups, I have had three backfires, all after turning off the ignition. Does anyone on the list have an idea about what might be causing this? George in Milwaukee 701 912UL ________________________________ Message 14 ____________________________________ Time: 07:55:53 AM PST US From: "Jari Kaija (LapTop2)" Subject: Re: Zenith-List: Backfire or Afterfire ...or did you mention fire in the carburetor's intake? ________________________________ Message 15 ____________________________________ Time: 09:04:12 AM PST US From: "Kevin L. Rupert" Subject: Re: Zenith-List: Backfire or Afterfire Mr. Pilot, Ever hear of *AD 76-07-12*,* BENDIX IGNITION SWITCHES? *KLR* * ________________________________ Message 16 ____________________________________ Time: 09:40:40 AM PST US From: "Robin Bellach" <601zv@ritternet.com> Subject: Re: Zenith-List: Backfire or Afterfire I believe he clearly said "AFTER I do a full power run-up," not DURING. Do not archive. ----- Original Message ----- From: Jari Kaija (LapTop2) To: zenith-list@matronics.com Sent: Tuesday, September 04, 2007 9:52 AM Subject: Re: Zenith-List: Backfire or Afterfire You are doing WHAT! Turning off ignition, while engine runs at maximum speed? What kind of test is this? Newer heard and I have quite a lott of experience with single piston aeroplanes, since I got my PPL license -96! Don't destroy your engine. Think a while! When you turn ignition off and engine have such kind of rpm. All gasoline/air mix will flow to muffler, because that mix didn't blow out in the cylinders. And muffler, when there is enough gas/air mix in a hot "steel botle", WILL catch fire!!!! ----- Original Message ----- From: george.mueller@aurora.org To: zenith-list@matronics.com Sent: Tuesday, September 04, 2007 4:58 PM Subject: Zenith-List: Backfire or Afterfire I am at the point of doing full power run-ups with my Zenith 701 with a rotax 912 UL 80hp installed with a Skyshops firewall forward kit. When I do a full power run up, I get a backfire (or afterfire maybe) after I turn the ignition key to "off". When I taxi around keeping the engine to around 2,000 rpm, this does not happen after shutdown, only after I do a full power run-up. Everything else seems normal as far as I can tell, the engine starts really well, seems to run smoothly, idles well. But after doing three full power run ups, I have had three backfires, all after turning off the ignition. Does anyone on the list have an idea about what might be causing this? George in Milwaukee 701 912UL href="http://www.matronics.com/Navigator?Zenith-List">http://www.matron href="http://forums.matronics.com">http://forums.matronics.com ________________________________ Message 17 ____________________________________ Time: 11:10:04 AM PST US From: Trainnut01@aol.com Subject: Re: Zenith-List: Backfire or Afterfire When I was involved with Nascar during the eighties several times during each weeks testing we would do a "Plug check" The procedure required the driver to run several hot laps, then right at the end of the back straight he would turn off the ignition (at full throttle), take the car out of gear, and coast to the pits. The crew would then push the car back to the garage, quickly remove the sparks plugs and rush them to the Champion Spark Plug trailer to have them "read" by the Champion Rep. The plugs were then returned to us with notations as to which ones should have gaskets added and which ones should have gaskets removed. Apparently the plug temp can be controlled by gasket thickness. I did not understand this at the time (not in my job description) and I don't understand it now but I do know that cutting the ignition at full throttle told somebody something. Carroll do not archive http://discover.aol.com/memed/aolcom30tour ________________________________ Message 18 ____________________________________ Time: 12:08:27 PM PST US From: Crvsecretary@aol.com Subject: Re: Zenith-List: Backfire or Afterfire I've heard of this procedure to check the size of the main jet in the carburator and the heat range of the plug. Adding & removing gaskets might change the amount of heat the plug can shed to the cylinder head, but typically heat range is built into the plug. Tracy Smith Naugatuck, CT Do Not Archive In a message dated 9/4/2007 1:11:10 PM Eastern Standard Time, Trainnut01@aol.com writes: When I was involved with Nascar during the eighties several times during each weeks testing we would do a "Plug check" The procedure required the driver to run several hot laps, then right at the end of the back straight he would turn off the ignition (at full throttle), take the car out of gear, and coast to the pits. The crew would then push the car back to the garage, quickly remove the sparks plugs and rush them to the Champion Spark Plug trailer to have them "read" by the Champion Rep. The plugs were then returned to us with notations as to which ones should have gaskets added and which ones should have gaskets removed. Apparently the plug temp can be controlled by gasket thickness. I did not understand this at the time (not in my job description) and I don't understand it now but I do know that cutting the ignition at full throttle told somebody something. Carroll do not archive http://discover.aol.com/memed/aolcom30tour ________________________________ Message 19 ____________________________________ Time: 12:41:51 PM PST US From: MacDonald Doug Subject: Re: Zenith-List: Backfire or Afterfire George, I have a similar set up but am still about six months away from run-ups. That being said, sounds like you could have a mixture issue (running rich and loading up the exhust with unburned fuel) but I would be more suspicious of fuel quality. Maybe try a different souce for your fuel. Might be stale fuel or something. Food for thought at least. Doug MacDonald CH-701 Scratch Builder, 912 UL NW Ontario, Canada Working on throttle assy. --- george.mueller@aurora.org wrote: > I am at the point of doing full power run-ups with > my Zenith 701 with a > rotax 912 UL 80hp installed with a Skyshops firewall > forward kit. When I > do a full power run up, I get a backfire (or > afterfire maybe) after I turn > the ignition key to "off". When I taxi around > keeping the engine to > around 2,000 rpm, this does not happen after > shutdown, only after I do a > full power run-up. Everything else seems normal as > far as I can tell, the > engine starts really well, seems to run smoothly, > idles well. But after > doing three full power run ups, I have had three > backfires, all after > turning off the ignition. Does anyone on the list > have an idea about what > might be causing this? > > > George in Milwaukee > 701 912UL ________________________________ Message 20 ____________________________________ Time: 12:48:17 PM PST US From: "Kevin L. Rupert" Subject: Zenith-List: (no subject) I know this has nothing to do with Corvairs but I found it interesting reading and thought the list might too. Kevin R. C/XL ________________________________ Message 21 ____________________________________ Time: 01:06:48 PM PST US From: David Downey Subject: Re: Zenith-List: Backfire or Afterfire The only way to get an accurate and readable color condition on the plug is to shut down at high throttle. Allowing the engine to come down through th e rpm and power bands will contaminate the purity og the data to be extract ed by "reading" the plugs. I am fascinated by the gasket shifting though; w hat was being learned/accomplished there?=0A =0ADave Downey=0AHarleysville (SE) PA=0A100 HP Corvair=0A=0A=0A=0A----- Original Message ----=0AFrom: "Cr vsecretary@aol.com" =0ATo: zenith-list@matronics.com =0ASent: Tuesday, September 4, 2007 3:07:02 PM=0ASubject: Re: Zenith-List: Backfire or Afterfire=0A=0A=0AI've heard of this procedure to check the siz e of the main jet in the carburator and the heat range of the plug. Adding & removing gaskets might change the amount of heat the plug can shed to th e cylinder head, but typically heat range is built into the plug.=0A =0ATra cy Smith=0ANaugatuck, CT=0ADo Not Archive=0A =0A =0A =0AIn a message dated 9/4/2007 1:11:10 PM Eastern Standard Time, Trainnut01@aol.com writes:=0AWhe n I was involved with Nascar during the eighties several times during each weeks testing we would do a "Plug check" The procedure required the driver to run several hot laps, then right at the end of the back straight he wou ld turn off the ignition (at full throttle), take the car out of gear, and coast to the pits. The crew would then push the car back to the garage, qui ckly remove the sparks plugs and rush them to the Champion Spark Plug trail er to have them "read" by the Champion Rep. The plugs were then returned to us with notations as to which ones should have gaskets added and which one s should have gaskets removed. Apparently the plug temp can be controlled b y gasket thickness. I did not understand this at the time (not in my job de scription) and I don't understand it now but I do know that cutting the ign ition at full throttle told somebody something.=0ACarroll=0A =0Ado not arch ===0A=0A=0A =0A__________________________________________________ __________________________________=0ANeed a vacation? Get great deals=0Ato amazing places on Yahoo! Travel.=0Ahttp://travel.yahoo.com/ ________________________________ Message 22 ____________________________________ Time: 01:07:47 PM PST US From: Terry Phillips Subject: Re: Zenith-List: Static ports Dave I am planning on using the Dynon AOA Pitot also and using the dual static port kit from Van's ($19). I hope you'll post a photo or two of the pitot installation after you get it in and working. I'm thinking of adding in the surplus differential pressure gage that is commonly used as an LRI idicator and using the Dynon EFIS to calibrate a scale for the gage. (I'm paranoid about failures of electronic gear and like analog backups.) Terry At 10:42 AM 9/4/2007 +0100, you wrote: >I am planning on fitting the Dynon AOA Pitot head to the 601XL. This does >not have a static port, so I will fit ports on either side of the fuselage. > >I understand the location is critical, so does anyone know where I should >put them (practical suggetsions only - this is a family list!!). > >I have tried the obvious line of e-mailing Zenith, but no response at all. > >Dave Johnson > >CH601XL form a CZAW kit Terry Phillips ttp44~at~rkymtn.net Corvallis MT 601XL/Jab 3300 slow build kit - Rudder done--finally; working on the stab http://www.mykitlog.com/N47TP/ ________________________________ Message 23 ____________________________________ Time: 01:44:16 PM PST US Subject: Zenith-List: Re: Static ports From: "Gig Giacona" DrEd, that's a great idea IF you didn't seal up the wings 3 years ago. Terry, A back-up for the AOA really? While nice it is hardly even bordering on critical. Mark, Thanks. I've been looking for a place to put the static ports in for the exact same reason as Dave. -------- W.R. "Gig" Giacona 601XL Under Construction See my progress at www.peoamerica.net/N601WR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=132754#132754 ________________________________ Message 24 ____________________________________ Time: 01:49:23 PM PST US Subject: Zenith-List: Re: (no subject) From: "Gig Giacona" Well what do you know. The FAA does care about us Auto Coversion guys. -------- W.R. "Gig" Giacona 601XL Under Construction See my progress at www.peoamerica.net/N601WR Read this topic online here: http://forums.matronics.com/viewtopic.php?p=132755#132755 ________________________________ Message 25 ____________________________________ Time: 03:26:52 PM PST US From: "Bill Naumuk" Subject: Re: Zenith-List: Re: Static ports Zodie- What if they're integral with the pitot? Per Zenith, the attached. Bill Naumuk HDS Fuse/Corvair Townville, Pa ----- Original Message ----- From: "ZodieRocket" Sent: Tuesday, September 04, 2007 7:14 AM Subject: RE: Zenith-List: Re: Static ports > > Measurement I use in 150mm down from the upper longerons and 150 mm back > from the firewall rivet line. Ensure to install two, one on either side > of cabin. > > Mark Townsend Alma, Ontario > Zodiac 601XL C-GOXL, CH701 just started > www.ch601.org / www.ch701.com / www.Osprey2.com > > -----Original Message----- > I asked this very question to ZAC at their Oshkosh booth this year. > Nick said the location of a static port was not all that critical. The > suggestion was on the fuselage side aft of the wing. > > Good luck, > > > > 9:31 AM > > > > > > ________________________________ Message 26 ____________________________________ Time: 03:46:08 PM PST US Subject: Zenith-List: Re: EA-81 Stratus Question -- Replacinig PSRU Bearings From: "Falcon" Larry Macfarland caught up with me on the Stratus list. Thanks everyone! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=132775#132775 ________________________________ Message 27 ____________________________________ Time: 04:52:23 PM PST US From: "n801bh@netzero.com" Subject: Re: Zenith-List: Backfire or Afterfire I drove those things back in the eighties and also built a few motors fo r them too. I read my own plugs to determine fuel mixture but more crit ical was looking for proper ignition timing. I still do it every few mon ths as my plane has a NASCAR style motor in it. It took me a couple of t imes of explaining to the control tower why I would actually shut off a good running motor about half way down the runway at full throttle. The backfire is caused by unburned fuel in the exhaust system, it is lit off by either the glowing exhaust valves or some real hot carbon build up in the pipes. All well built engines are dyno run before they get to the track and changing plug gaskets will "index"the ground strap on the plug to get optimal combustion. The slight difference in fuel mixture be tween cylinders is usually tweaked during flow testing of the intake man ifold and intake ports on a flow bench, this happens before the motor is assembledAfter reading the plugs I would determine if the timing is corr ect, then I would make a jet change if needed and as a last result I wou ld make a spark plug heat range change.If the original poster would let the motor cool a few minutes before shutting off the ignition it will pr obably not backfire. Do not archive When I was involved with Nascar during the eighties several times during each weeks testing we would do a "Plug check" The procedure required t he driver to run several hot laps, then right at the end of the back str aight he would turn off the ignition (at full throttle), take the car ou t of gear, and coast to the pits. The crew would then push the car back to the garage, quickly remove the sparks plugs and rush them to the Cham pion Spark Plug trailer to have them "read" by the Champion Rep. The plu gs were then returned to us with notations as to which ones should have gaskets added and which ones should have gaskets removed. Apparently the plug temp can be controlled by gasket thickness. I did not understand t his at the time (not in my job description) and I don't understand it no w but I do know that cutting the ignition at full throttle told somebody something.Carroll do not archive The only way to get an accurate and readable color condition on the plu g is to shut down at high throttle. Allowing the engine to come down thr ough the rpm and power bands will contaminate the purity og the data to be extracted by "reading" the plugs. I am fascinated by the gasket shift ing though; what was being learned/accomplished there? Dave DowneyHarleysville (SE) PA100 HP Corvair ======================== ======================== ======================== ======================== ======================== ============= ________________________________ Message 28 ____________________________________ Time: 05:01:58 PM PST US From: "JG" Subject: Re: Zenith-List: Backfire or Afterfire And make certain the throttle is held completely closed and the idle slowed right down. Do not archive. JG ----- Original Message ----- From: n801bh@netzero.com To: zenith-list@matronics.com Sent: Wednesday, September 05, 2007 9:50 AM Subject: Re: Zenith-List: Backfire or Afterfire I drove those things back in the eighties and also built a few motors for them too. I read my own plugs to determine fuel mixture but more critical was looking for proper ignition timing. I still do it every few months as my plane has a NASCAR style motor in it. It took me a couple of times of explaining to the control tower why I would actually shut off a good running motor about half way down the runway at full throttle. The backfire is caused by unburned fuel in the exhaust system, it is lit off by either the glowing exhaust valves or some real hot carbon build up in the pipes. All well built engines are dyno run before they get to the track and changing plug gaskets will "index"the ground strap on the plug to get optimal combustion. The slight difference in fuel mixture between cylinders is usually tweaked during flow testing of the intake manifold and intake ports on a flow bench, this happens before the motor isassembledAfter reading the plugs I would determine if the timing is correct, then I would make a jet change if needed and as a last result I would make a spark plug heat range change.If the original poster would let the motor cool a few minutes before shutting off the ignition it will probably not backfire. Do not archive When I was involved with Nascar during the eighties several times during each weeks testing we would do a "Plug check" The procedure required the driver to run several hot laps, then right at the end of the back straight he would turn off the ignition (at full throttle), take the car out of gear, and coast to the pits. The crew would then push the car back to the garage, quickly remove the sparks plugs and rush them to the Champion Spark Plug trailer to have them "read" by the Champion Rep. The plugs were then returned to us with notations as to which ones should have gaskets added and which ones should have gaskets removed. Apparently the plug temp can be controlled by gasket thickness. I did not understand this at the time (not in my job description) and I don't understand it now but I do know that cutting the ignition at full throttle told somebody something. Carroll do not archive The only way to get an accurate and readable color condition on the plug is to shut down at high throttle. Allowing the engine to come down through the rpm and power bands will contaminate the purity og the data to be extracted by "reading" the plugs. I am fascinated by the gasket shifting though; what was being learned/accomplished there? Dave Downey Harleysville (SE) PA 100 HP Corvair ------------------------------------------------------------------------- ----- /aolcom30tour/?ncid=AOLAOF00020000000982 href="http://discover.aol.com/memed/aolcom30tour/?ncid=AOLAOF00020000 000982" target=_blank>AOL.com. ">http://www.matronics.com/Navigator?Zenith-List tronics.com ________________________________ Message 29 ____________________________________ Time: 06:24:26 PM PST US From: "ZodieRocket" Subject: RE: Zenith-List: Re: Static ports That will work just fine Bill. The fuselage mount is for those who only have a Pitot tube only. Or an AOA. Mark Townsend Can-Zac Aviation Ltd. president@can-zacaviation.com www.can-zacaviation.com -----Original Message----- Zodie- What if they're integral with the pitot? Per Zenith, the attached. Bill Naumuk HDS Fuse/Corvair Townville, Pa ----- Original Message ----- 9:14 AM ________________________________ Message 30 ____________________________________ Time: 07:36:21 PM PST US From: Bob Sturgis Subject: Zenith-List: New to list Hi, I am bobefx in southern California. I am building a 601XL QB kit. I have the rudder, horz stab, elevator, left wing and landing gear done. I found some things that I am concerned about in the kit. 1. The fuel tank vent and quick drain holes in the leading edge skin did not line up with the tank. Any one had that problem? 2. The elevator stops were placed right next to the elevator hole, in the way of the bolt and nut to operate the elevator. Any one had that problem? 3. Some holes were smaller than they should have been to accept the rivet, and others were elongated. It seems that Zenith has a quality control problem. Has anyone had any problems with their QB kit and if so what? Thank you Bob ________________________________ Message 31 ____________________________________ Time: 07:43:30 PM PST US From: Bob Duns Subject: Re: Zenith-List: WW nose bowl disc Jeff: I too am planning to build my own nosebowl for 601HD/Corvair and am very much interested in your specs. The pics were great but measurements would sure help, also materials list used. The measurements that I found on WW website were minimal. Thanks. Bob D. Melfort, SK 601HD/Corvair ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith-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/zenith-list Browse Digests http://www.matronics.com/digest/zenith-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.