---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Fri 04/23/04: 18 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:51 AM - Re: N569Z Crash (Brett Ray) 2. 05:09 AM - Re: Reduction Ratios (Phil Raker) 3. 05:29 AM - fuel tank switching (Thomas F Marson) 4. 06:39 AM - Re: Re: Reduction Ratios (RUSSELL JOHNSON) 5. 07:12 AM - EGTs (john H) 6. 07:46 AM - Re: EGTs (Trampas) 7. 08:23 AM - Re: Header tanks, balance lines,etc () 8. 08:33 AM - fuel systems etc. (RiteAngle3@aol.com) 9. 09:05 AM - Re: EGTs (Leo J. Corbalis) 10. 09:23 AM - Re: fuel tank switching (Bill Cardell) 11. 10:12 AM - Re:Header tanks, balance lines, etc (Kevin W Bonds) 12. 10:40 AM - Re: Wynn sightings? (brian HOPE) 13. 11:30 AM - Re: Re:Header tanks, balance lines, etc () 14. 11:30 AM - Re: Re:Header tanks, balance lines, etc (Jeffrey Davidson) 15. 07:28 PM - Re: Re:Header tanks, balance lines, etc (Larry Martin) 16. 07:55 PM - Re: Suzuki Engine Conversion, CH701 (roy vickski) 17. 08:29 PM - engine (Ron Lee) 18. 10:56 PM - Re: engine (Brett Ray) ________________________________ Message 1 _____________________________________ Time: 12:51:11 AM PST US From: "Brett Ray" Subject: Re: Zenith-List: N569Z Crash --> Zenith-List message posted by: "Brett Ray" If you hook up your fuel system just like the drawings show. With the 2 shut off valves and the "T" in the middle. Then the tanks will balance themselves if both valves are open. If you want to see this in action fill your tanks and park on a slope with on wing lower than the other. Then watch it dump fuel out of the low tank until they are balanced. That is something you will want to be aware of if parking some place that is not flat. You could empty a tank and not no it. Brett ________________________________ Message 2 _____________________________________ Time: 05:09:19 AM PST US From: Phil Raker Subject: Zenith-List: Re: Reduction Ratios --> Zenith-List message posted by: Phil Raker Jim: The one thing I've heard is that you DO NOT want to have your ratio be an even multiple (2:1, 3:1, etc.). That can easily set up a harmonic torsional vibration which can quickly destroy any prop. Probably the worst possible combination would be a three cylinder engine (like the Suzuki 1000), a 3:1 reduction and a 3-blade prop. If all the power pulses and blade passages are lined up the right (or wrong) way, the torsional vibration begins. It would also be hard on engine mounts, both before and after the prop breaks. Regards, Phil Raker N556P HDS/Stratus ~85% complete, left wing mounted this week > > From: "Jim Fosse" > Subject: Re: Zenith-List: Suzuki Engine Conversion, CH701 > > --> Zenith-List message posted by: "Jim Fosse" > > Does anyone have > recommendations or data on the best prop speed which should translate > to the required reduction ratio? > __________________________________ http://photos.yahoo.com/ph/print_splash ________________________________ Message 3 _____________________________________ Time: 05:29:53 AM PST US From: "Thomas F Marson" Subject: Zenith-List: fuel tank switching --> Zenith-List message posted by: "Thomas F Marson" Pie ChartsRecently the Zenith List has addressed the subject of designing a fuel system of more than one tank that would require switching from tank to tank to use all of the fuel. This discussion has developed since one of the Zenith members reported himself to be alive and well after a crash caused when he improperly switched fuel tanks on downwind. The engine quit and he was unable to do a restart before contacting trees. He didn't say but we are to assume the plane was near or total loss. Importantly he survived. This member to his great credit and for all of our benefit held back nothing as to the reason for the crash and accepted that he was completely at fault for switching tanks near the ground and failure to do a proper switch at that. This has brought up lots of discussion of the advisability of designing such as system into our experimental planes. Some have said they see no reason for designing any system where it is necessary to switch tanks at all. Even with multiple tanks why not have all feed at once. Others have said it maybe necessary to switch tanks on demand to keep the plane balanced side to side or front to rear as fuel burns off. Others have said that maybe planes are designed with the need to switch "because they have always been designed that way". The impression being that it was never necessary but designers were just going on convention. Other writer chimed in to say he couldn't personally see why any system would be designed that way. One of the reasons for being able to select tank to tank used to be said that when you ran a tank dry you knew for sure how much fuel remained in that tank because the engine quit. Of course prudent pilots would be aware of tank status and would not let that happen at low altitudes. When the engine stopped you switch from an now known empty tank to one with fuel. I don't suspect there are any records to indicate how often that at this point the valve malfunctioned, stuck and could not be switched. Bingo here comes the trees!!! Accident records are quite common where there was fuel remaining in one tank or more tanks while the one being operated off of was dry. Why did the pilot not switch to a tank with fuel before he crashed ????? Lots of talk with our experimentals (esp. with low wings with tanks in them). of how to pump, where to position pump, at tank outlet or elsewhere, whether to have pumps and valves in addition. Seems to be pretty much a consensus that pumps should be as close as possible to the wing tank outlet and if possible at or below the level of the outlet as that will lessen the possibility of vapor lock or other pump malfunction as the pump will be "pushing fuel" as opposed to sucking fuel. I am in that camp! Also seems most favor with this set up to use electric pump on off switching as the preferred method of moving fuel (no need to introduce a valve into the system. I am in that camp too. Always use both pumps on for takeoff and landing. If a valve is in the system because there is no other choice, buy the best you can. I have flown lots of certified planes where a valve was so stiff there was a question of being able to turn it. I think back in my earlier ( and less experienced years) where I still flew a plane that it was possible to turn the valve but questionable that the valve handle could twist off as the action was so stiff. Well everyone else was flying it so why not me!!!! Dumb. I also used to be of the camp that on long range flights fly the plane (at altitude) till a tank ran dry and then switch to one with fuel. Well that is the way I was taught. I don't think I would ever do that now since I have become more experienced. What if the valve becomes stuck at just that time. Anyway since most of us who are on these lists are concerned with building an experimental plane and have a lot to say about the fuel systems, I recommend if at all possible to design a system that will have all tanks feed at the same time maybe into a header tank. If it is at all possible to eliminate pumps and go with simple gravity feed do that. If possible include some balance tubes between two or more tanks so they will empty more or less evenly and by gravity flow. This is the system used by Citibrias for years. One of the more standard types of system (used on older Champs and others) is a gravity flow from a wing tank to a cowl tank the then feed the engine. The pilot uses a on off valve to allow fuel to flow from the wing tank into the "main" tank in the cowl when the main tank is low enough to accept fuel. That is a pretty standard system and works well. With such a system I never let my main tank get low enough to be unable to reach an airfield before downloading some fuel from the wing tank. I have designed such a system in my current plane, a Dakota Hawk. I don't know if this rambling discussion helpful at all to experience pilots, you have probably been through this though process a thousand times. I am writing this because there a lot of newbies and lurkers out there who are just now thinking about it. Every few months one can safely bet there are new people who are just now coming on line and this may help them. A couple more thoughts. The fuel strainers systems usually employed start with a Finger screen in each fuel tank. then a gascolater with a fine screen and then a very fine screen in the carb inlet. It should be noted that some see the coarse screen in the finger strainer and say " who needs that, I have finer screens downstream". The finger strainer is really a way to keep that small port in the bottom of the fuel tank open to flow from gross impurities such as a moth or a leaf or some other large object. Some people feel the need to add an in line filter, most will not pass water. If the filter becomes water logged from this type all flow (including fuel )will stop. I personally believe the standard system of screens I described above is more than adequate. Frequently adding just one more safety might be the reason the whole system shuts down. Can't highly enough recommend Tony Binglis books SportPlane Construction and Firewall Forward for good information on all types of fuel systems. The records show that most engine stoppages are the result of fuel flow interruption from any of a number of sources. Keep your systems simple and make sure you maintain it well. Hope this helps someone. Tom Marson ________________________________ Message 4 _____________________________________ Time: 06:39:24 AM PST US From: "RUSSELL JOHNSON" Subject: Re: Zenith-List: Re: Reduction Ratios --> Zenith-List message posted by: "RUSSELL JOHNSON" > Jim: > The one thing I've heard is that you DO NOT want to have your ratio be an > even multiple (2:1, 3:1, etc.). That can easily set up a harmonic torsional > vibration which can quickly destroy any prop. . > > Regards, > Phil Raker N556P HDS/Stratus ++++++++++++++++++++ The idea behind an odd or unbalanced ratio is to allow for the hunting tooth. In the design of a gear reduction unit, it prevents a gear tooth from coming in contact with the same opposing gear tooth before being in contact with all the other gear teeth on the opposing gear. (I know, clear as mud!) R. Johnson 601/HDS do not archive ________________________________ Message 5 _____________________________________ Time: 07:12:43 AM PST US From: "john H" Subject: Zenith-List: EGTs --> Zenith-List message posted by: "john H" I'm in the proicess of wiring up the EIS system for my 601 with a Rotax 912ul.My unit came with 4 EGT sensors. My question is do I need to install all 4? Since the bing carbs are self compensating for altitude and 2 cylinders are fed by one carb wouldn't 2 sensors be sufficient? IF 2 are enough, then should one be on one of the forward cylinders and one on the rear, or would both on the rear cylinders be the way to go? Anyone have any thoughts? Thanks in advance John ________________________________ Message 6 _____________________________________ Time: 07:46:00 AM PST US From: "Trampas" Subject: RE: Zenith-List: EGTs --> Zenith-List message posted by: "Trampas" Well I would go ahead and use all four. The reason being is that the EGTs are nice to monitor as a way to determine problems with your engine. For example if a vacuum leak occurs at intake you can tell from EGTs. If a plug is miss firing you can tell which one from the EGTs. Also if you have data logging with your EIS system it is nice to keep a history of your engine parameters then you can see what happens as the engine wears or when plugs wear. This information is again very handy when you are trying to find a problem. I can send you a sample data log I did no my wife's car using my engine monitor which shows a problem with one of the cylinders using just the EGTs. Regards, Trampas Stern www.sterntech.com -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of john H Subject: Zenith-List: EGTs --> Zenith-List message posted by: "john H" I'm in the proicess of wiring up the EIS system for my 601 with a Rotax 912ul.My unit came with 4 EGT sensors. My question is do I need to install all 4? Since the bing carbs are self compensating for altitude and 2 cylinders are fed by one carb wouldn't 2 sensors be sufficient? IF 2 are enough, then should one be on one of the forward cylinders and one on the rear, or would both on the rear cylinders be the way to go? Anyone have any thoughts? Thanks in advance John ________________________________ Message 7 _____________________________________ Time: 08:23:05 AM PST US Subject: RE: Zenith-List: Header tanks, balance lines,etc From: --> Zenith-List message posted by: Why not, instead of all this computer time, consider the ZENITH SYSTEM: a headertank, of your choice of size, fed by two wingtanks, again, of your choice, joined by a tee, connected to the headertank with a fill line that requires a TRANSFER pump. Rotax's have a gear-driven fuel pump to draw from the headertank, through a filter. This was the standard back in the mid-90's. It has worked well for me, and every single other builder who used it, to the best of my knowledge. Why one would wish to "manage", or mismanage, more likely, his or her fuel is totally beyond comprehension! But, of course keep typing, don't build or fly: that's dangerous! GGP ________________________________ Message 8 _____________________________________ Time: 08:33:19 AM PST US From: RiteAngle3@aol.com Subject: Zenith-List: fuel systems etc. --> Zenith-List message posted by: RiteAngle3@aol.com I have never in my 40+ years of driving run out of gas in a vehicle, why would I think I would in an aircraft? Remember, MURPHY still lives, no one plans on having an accident, that is a known fact. Why do pilots neglect lowering the landing gear in an aircraft they have been flying for years? Accidents are normally caused by distractions, not just forgetting. An accident is just that, an accident, which normally has many things leading up to it. However as is known, some just happen. Remember Murphy. Safety is NO accident Elbie ________________________________ Message 9 _____________________________________ Time: 09:05:22 AM PST US From: "Leo J. Corbalis" Subject: Re: Zenith-List: EGTs --> Zenith-List message posted by: "Leo J. Corbalis" I have 4 EGTs on my 912UL and there is a considerable differience between them. You can't moniter the CHT because the liquid cooling smooths out the readings. You have the capability of monitering all 4 cylinders. The more you know, the better off you are. You may not be happier but you know what's happening. Leo Corbalis > --> Zenith-List message posted by: "john H" > > I'm in the proicess of wiring up the EIS system for my 601 with a Rotax 912ul.My unit came with 4 EGT sensors. My question is do I need to install all 4? Since the bing carbs are self compensating for altitude and 2 cylinders are fed by one carb wouldn't 2 sensors be sufficient? IF 2 are enough, then should one be on one of the forward cylinders and one on the rear, or would both on the rear cylinders be the way to go? Anyone have any thoughts? > Thanks in advance > John > ________________________________ Message 10 ____________________________________ Time: 09:23:50 AM PST US From: Bill Cardell Subject: RE: Zenith-List: fuel tank switching --> Zenith-List message posted by: Bill Cardell Tom, Thank you for a great synopsis! This one is going in my archives,as I'm real close to doing the fuel system. As soon as I get my stratus heads back to give me some inspiration.. do not archive Bill Cardell (TurboDog's Dad) bill@flyinmiata.com Flyin' Miata 1-800-359-6957 (sales only) 970-242-3800 (tech support) http://flyinmiata.com http://flyinprotege.com -----Original Message----- From: Thomas F Marson [mailto:tmarson@pressenter.com] Subject: Zenith-List: fuel tank switching --> Zenith-List message posted by: "Thomas F Marson" Pie ChartsRecently the Zenith List has addressed the subject of designing a fuel system of more than one tank that would require switching from tank to tank to use all of the fuel. This discussion has developed since one of the Zenith members reported himself to be alive and well after a crash caused when he improperly switched fuel tanks on downwind. The engine quit and he was unable to do a restart before contacting trees. He didn't say but we are to assume the plane was near or total loss. Importantly he su ________________________________ Message 11 ____________________________________ Time: 10:12:33 AM PST US From: "Kevin W Bonds" Subject: Zenith-List: Re:Header tanks, balance lines, etc --> Zenith-List message posted by: "Kevin W Bonds" George wrote: >But, of course keep typing, don't build or fly: that's dangerous! George Excuse me for saying, but that was a little harsh. I for one am glad to here other ideas. I think the fuel system debate is a productive one. I have gotten a lot of good ideas. It, and the account of the recent fuel switching accident, have made me rethink my fuel system ideas. Up till this time my rough ideas about fuel system design were starting to get very complex. I am now thinking about simplicity and less about squeezing every ounce of performance out of my plane ie removable wing locker tanks, etc. Although I still have not ruled out things like the removable wing tank lockers completely, I will in the end rule them out over safety if so needed (may just be too much trouble in the end anyway). Again Just ideas. Eveyone should take them with a grain of salt. Thank you Jeff for your honesty--I may be one of the lives you saved by being so. It takes a big man to admit he made a mistake. And a pilot who dosen't want to admit when he has made a mistake is a dangerous one. Kevin ________________________________ Message 12 ____________________________________ Time: 10:40:58 AM PST US From: "brian HOPE" Subject: Re: Zenith-List: Wynn sightings? --> Zenith-List message posted by: "brian HOPE" Hi Steve, William gave a number of forums on the Corvair and his 601XL was featured on the Zenair stand. It is ready to fly once FAA get the paperwork completed. No doubt a report will be posted on the website once performance data is known. Two Corvair engined KR2s on the flightline and plenty of Corvair parts and a complete unit on the Contact stand ensured the engine got good exposure. There certainly seems to be a rapidly growing interest in this affordable and straightforward engine conversion. ________________________________ Message 13 ____________________________________ Time: 11:30:26 AM PST US Subject: RE: Zenith-List: Re:Header tanks, balance lines, etc From: --> Zenith-List message posted by: It was deliberately harsh. "Balance lines" add complexity and aren't needed to fly; one might even note they aren't present in the ZENITH STANDARD CONFIGURATION. The Zodiac can be built and flown as a simple aircraft. I enjoy all the "features" I don't have to worry about so I can fly the plane, fly the plane, fly the plane: no flaps, no RG, no carb-heat, no mixture, no prop pitch, no tank-selector! And I'll throw in no attitude indicator so I can fly around on the edge of a stall! GGP ________________________________ Message 14 ____________________________________ Time: 11:30:26 AM PST US From: "Jeffrey Davidson" Subject: Re: Zenith-List: Re:Header tanks, balance lines, etc --> Zenith-List message posted by: "Jeffrey Davidson" Kevin, Even though George certainly doesn't need help from me, please let me say that the thing about fuel systems threads is that there is no definitive answer. Every solution has a problem. Even gravity feed header tanks can be unported in climbs or unusual attitudes stopping the fuel flow. In my case, my Chief Pilot wife simply will not allow a header tank (fire ball) in the Zodiac. There are innumerable messages about fuel systems in the archives that cover just about every facet. Wordy dissertations don't help. In the end, everyone has to weigh the options and the factors they consider most important to come to a conclusion on their own. And for those of us who learned flying Pipers, switching tanks is nothing new. I apologize in advance if I offend. Jeff Davidson ________________________________ Message 15 ____________________________________ Time: 07:28:40 PM PST US From: "Larry Martin" Subject: Re: Zenith-List: Re:Header tanks, balance lines, etc --> Zenith-List message posted by: "Larry Martin" George, Balance tubes are complex? It's a tube or two in as straight line as possible between two tanks. Don't see much complexity there. The Zenith Standard Configuration may be the best thing going, but I for one like to hear and consider other ideas. And, I hope to contribute ideas. One thing I really like about this group is that we have people who are capable of thinking out of the box, present ideas, without worrying about someone jumping on their case. Then we have those who are "Standard Configuration" types and that's ok too. There's room for both, just keep it friendly, agree to disagree and be open minded. Off my box now. Larry Do Not Archive. ----- Original Message ----- From: george.pinneo@ngc.com To: zenith-list@matronics.com Sent: Friday, April 23, 2004 1:30 PM Subject: RE: Zenith-List: Re:Header tanks, balance lines, etc --> Zenith-List message posted by: It was deliberately harsh. "Balance lines" add complexity and aren't needed to fly; one might even note they aren't present in the ZENITH STANDARD CONFIGURATION. The Zodiac can be built and flown as a simple aircraft. I enjoy all the "features" I don't have to worry about so I can fly the plane, fly the plane, fly the plane: no flaps, no RG, no carb-heat, no mixture, no prop pitch, no tank-selector! And I'll throw in no attitude indicator so I can fly around on the edge of a stall! GGP --- Version: 6.0.581 / Virus Database: 368 - Release Date: 2/9/2004 ________________________________ Message 16 ____________________________________ Time: 07:55:17 PM PST US From: roy vickski Subject: Re: Zenith-List: Suzuki Engine Conversion, CH701 --> Zenith-List message posted by: roy vickski Jim, I recommend Richard Finches "Converting Auto engines for Experimental Aircraft". The overriding theme is to copy what works. That said, a rotax 912 is within a 100cc engine displacement of your suzuki 1300, so one should be able to apply what is known about it to your 1300. Personally I have been considering engines for my 701 for almost 2 years, I chose a corvair, based on availability, simplicity and affordability, #2 choice would be a toss up between a 2.5 vw and suzuki 1300. But to be sure your 1300 stands a better chance of coming in at under 200 lbs with electric start than my corvair hand prop does. Educate yourself on redundancy and simlicity and remember that cheap doesn't always equal good. Roy 701 plans, fuse on gear, building doors, motor hanging from firewall, exhaust to be made, cowl, shrouds, baffles, yet to be made. My goodness there is a lot left to do. P.S. stay away from the 1 -Litre 3 cylinder, bad vibes, literally. Roy do not archive __________________________________ http://photos.yahoo.com/ph/print_splash ________________________________ Message 17 ____________________________________ Time: 08:29:09 PM PST US From: "Ron Lee" Subject: Zenith-List: engine --> Zenith-List message posted by: "Ron Lee" I am ready for an engine for my CH 701. I need the money so must sell my Titan Tornado1. Just reduced the price $1,000.00. Check it out on barnstormers.com Ron Lee ________________________________ Message 18 ____________________________________ Time: 10:56:22 PM PST US From: "Brett Ray" Subject: Re: Zenith-List: engine --> Zenith-List message posted by: "Brett Ray" How about a Harley for it. I may make you a deal because I was wanting to build a 701 to put it in. But that could save me alot of time. And I am real busy right now. I am puting the 95ci. 110 motor in my 601XL and have the 88ci. 80hp ready to go in. Brett www.hog-air.com do not archive