From: gperry@usit.com Date: Sun, 2 Aug 1998 18:19:40 -0400 (EDT) Subject: COZY: Chapter 15 questions Whoa...Dorothy, I think we just left Kansas! I'm working on Chapter 15 of the Cozy Mark IV plans and have some questions about the drawing on page 2. 1) The drawing shows two clamps that apparently encircle the nuts on the coupling going into and out of the gascolator. The gascolator (with the wire retainer) is about 3" in diameter. How can you attach these nuts against the firewall if they have to be at least 1 1/2" away from it for gascolator to fit? 2) How is the Skinner Solenoid Valve mounted? In the drawing, it appears that it is mounted so that its long axis is horizontal - but is this with the end that has the fittings close to, or away from the firewall? Is is supported in any way? 3) I'm assuming that the AN 816 6D coupling shown in the plans going into the Skinner Valve must be incorrect. Mine sure won't fit the tapped hole in the Skinner Valve. Should this be an AN 816 6 2D fitting instead? 4) These is no indication on the Skinner Valve as to which side is "in" and which port is "out". The only markings are "1" and "2". Does it make a difference? 5) There is a plug shown on the top port of the gascolator but it is not specified in the drawing. Anyone know what size this is so I can order one? Any help would be greatly appreciated. Thanks... Gregg Perry From: cdenk@ix.netcom.com Date: Sun, 2 Aug 1998 20:48:53 -0500 (CDT) Subject: Re: COZY: Chapter 15 questions Re: Gascolator mount: Depends on what yours looks like. But in general, a steel (all fittings in the engine area should be steel) bulkhead fitting through the firewall, with the gascolator pipe threaded directly to it. Mine is a spruce, which has a matching bracket through bolted to the firewall. I have a weldon certified rotary pump for my injectors, can't help with the facet. I think the top fitting is 1/4" pipe female. From: gperry@usit.com Date: Wed, 5 Aug 1998 21:26:53 -0400 (EDT) Subject: COZY: Chapter 15 questions Thanks to those who answered my original question about the Chapter 15, page 2 drawing. I still am in the dark about how to mount the Skinner Valve. Someone suggested a bracket but there are no drawings and I'm not THAT good an engineer! If anyone has ideas I'd love to hear them. I also heard from a couple of folks, who I consider to be quite knowledgeable, about their concern over the use of aluminum fittings on the firewall. This same drawing on page 2 clearly calls out for aluminim fittings. Interesting... Gregg Perry From: gperry@usit.com Date: Wed, 19 Aug 1998 21:27:34 -0400 (EDT) Subject: COZY: Fuel Line Fittings Hello all, Last week, I posted a couple of questions about the Chapter 15 - page 2 drawing in the Cozy Mark IV plans. The replies I got essentially said: 1) use a firewall fitting of some sort 2) use steel fittings aft of the firewall OK, Steve Sharp (and his nifty metal lathe) is helping me come up with a firewall fitting that will allow the gasocolator to stand free of the firewall BUT...what is the purpose of using steel fittings if they are attaching to an aluminum gascolator and aluminum fuel lines? Am I missing something here? Is this why the Mark IV plans call for aluminum fittings aft of the firewall? I have NO experience in this area so I'd really appreciate some thoughts from the experts. Thanks... Gregg Perry From: cdenk@ix.netcom.com Date: Wed, 19 Aug 1998 21:43:44 -0500 (CDT) Subject: Re: COZY: Fuel Line Fittings On 08/19/98 21:27:34 you wrote: > >Hello all, > > Last week, I posted a couple of questions about the Chapter 15 - page 2 >drawing in the Cozy Mark IV plans. The replies I got essentially said: > 1) use a firewall fitting of some sort > 2) use steel fittings aft of the firewall > >OK, Steve Sharp (and his nifty metal lathe) is helping me come up with a >firewall fitting that will allow the gasocolator to stand free of the >firewall BUT...what is the purpose of using steel fittings if they are >attaching to an aluminum gascolator and aluminum fuel lines? Am I missing >something here? Is this why the Mark IV plans call for aluminum fittings >aft of the firewall? I have NO experience in this area so I'd really >appreciate some thoughts from the experts. >Thanks... > Gregg Perry > > > The issue is aluminum is more subject to stress riser fatigue cracking than most steel alloys. There have been known to occur cracked aluminum fittings in the engine compartment where there is more vibration. This is in addition to the melting fire concerns. For the gascolator it should not be necessary to machine a special piece. Check your local industrial distributor (Parker Hannifin, etc.) You need a bulkhead fitting with J.I.C. 37 degree flare one end, and male pipe thread to fit the gascolator. All the flared fittings are the 37 degree variety. The engine driven fuel pump, bendix fuel injection, and my Weldon fuel pump are all "O-Ring" type fittings, get the fittings at the same hyd. dist. All fitting should be the forged one piece type, and not the several piece brazed type. I got all my hoses, only Teflon type with fire sleeve from Varga Enterprises, 1-800-966-6936. Teflon hoses are somewhat fragile when it comes to bending beyond their minimum radius. While at OSH, I saw Parker Stratoflex hose. It is firesleeved teflon, the construction appeared to be superior to the aeroquip that I now have. Don't know how price compares, but think I would get the Stratoflex and shop price for that. Date: Wed, 19 Aug 1998 22:29:56 -0400 From: David Domeier Subject: Re: COZY: Fuel Line Fittings Gregg, re ".what is the purpose of using steel fittings if they are attaching to an aluminum gascolator and aluminum fuel lines? Am I missing something here?" The original LEZ plan called for all aluminum in keeping with a philosophy of building as light as possible. Somewhere along the way a Long EZ had an inflight engine fire, the exact cause I think was never determined, and shortly thereafter came a change to steel in the engine compartment - flight controls and fuel fittings. The real reason for the change was probably more legal than practical...I'm not convinced all steel is going to make that much difference with an inflight engine fire. My feeling is a regular inspection of the exhaust system is a better idea. If the fire does not get started, aluminum is just fine. dd Date: Wed, 19 Aug 1998 23:21:34 -0400 From: "Marc J. Zeitlin" Subject: Fwd: COZY: Fuel Line Fittings Gregg Perry wrote; >OK, Steve Sharp (and his nifty metal lathe) is helping me come up with a >firewall fitting that will allow the gasocolator to stand free of the >firewall... I don't think there's any reason to do that. Look at Chapter 21, Page 8, section A-A (this is the same picture as in Chapter 15, but Ch. 15 is missing Section A-A). This shows a spacer to hole the gascolator clamps away from the firewall. No special brackets necessary. WRT your question regarding the Skinner valve, I think that the picture calls out a AN816-6D fitting, but if you look at the parts list in Ch. 2 Page 4, it calls out an AN816-6-2D reducing Nipple. I think that this is the part that goes into the bottom end of the valve. I have no clue how to attach the valve to the firewall (if it's even necessary) but I'd think that another spacer of the appropriate length and another clamp around the AN818-6D Nut (like for the gascolator, except only one) would work OK. WRT the issue of steel vs. aluminum fittings, I'm going to assume that the objection to aluminum is one of fire protection. However, unless you're going to use all steel behind the firewall for all your fuel line/fittings, one burnt hole in the line is no better than 5 or 6 :-). If the objection is over another issue, those objecting will have to spell out what it is. I wonder if there's ever been a burn through of an EZ style fuel system behind the firewall? -- Marc J. Zeitlin                     marcz@burnside.ma.ultranet.com 3 Sweetbriar Way                  http://www.ultranet.com/~marcz Acton, MA  01720                 http://cozy.canard.com/ From: cdenk@ix.netcom.com Date: Thu, 20 Aug 1998 07:45:34 -0500 (CDT) Subject: Re: COZY: Fuel Line Fittings On 08/19/98 22:29:56 you wrote: > >Gregg, > > re ".what is the purpose of using steel fittings if they are >attaching to an aluminum gascolator and aluminum fuel lines? Am I >missing something here?" > > The original LEZ plan called for all aluminum in keeping with a >philosophy of building as light as possible. Somewhere along the way a >Long EZ had an inflight engine fire, the exact cause I think was never >determined, and shortly thereafter came a change to steel in the engine >compartment - flight controls and fuel fittings. > > The real reason for the change was probably more legal than >practical...I'm not convinced all steel is going to make that much >difference with an inflight engine fire. My feeling is a regular >inspection of the exhaust system is a better idea. If the fire does not >get started, aluminum is just fine. > >dd > > > > > As I previously stated the issue is cracked fittings. As far a fire goes, the liquid can come to the exhaust. Several years ago I was adding a quart of oil to the 5.8Liter (351W) engine in my Ford Bronco (in the attached to the house garage), immediately after shutting down after highway driving. Spilled a small quantity of engine oil (Shell Rotella 15W-50) which dripped on to the exhaust manifold, with an instant small fire, which could have done major damage in short order. The fire extinguisher hanging on the wall 8 feet away did its job and just a dry powder cleanup was needed. On the Lycoming, the rocker cover gasket is directly above is a frequent place for leaks to start, right above a hot exhaust pipe. It is common to get as much as a cup of oil through the rocker area in 10 minutes, certainly enough to make a decent fire. Also there are other possiblities including a swallowed valve or cracked cylinder allowing the head to part ways from the cylinder. Big problems, anything you can do to minimize the effects is worthwile, in particular if not any more difficult to do (when ordering its easier, just leave off the "-D" on the part number), cost is not an issue when safety is concern. From: "Nat Puffer" Subject: Re: COZY: Fuel Line Fittings Date: Thu, 20 Aug 1998 11:01:39 -0500 Cozy builders, There was one engine compartment fire reported for a Long EZ, out of perhaps 1,000 flying. Burt's main concern was to ensure that the pilot had control of the airplane long enough to land if there were an engine compartment fire. That is when he made the change from .035 wall aluminum pushrods to .035 steel pushrods to the ailerons. He considered that the thin wall aluminum pushrods had the least fire resistance and was the most critical in terms of being able to land. He also recommended coating the firewall with an insulating type material. There are many items inside the engine compartment made of aluminum, starting with the engine itself, carb or throttle body, fuel lines, oil return lines, rudder pulley brackets, etc. We believe that the only significant source of an engine fire would be a fuel leak, and if so, the fire would go out if the fuel valve is shut off. The question is, how would anyone know if there is an engine compartment fire? We considered many possibilities, fusible link electrical warning system, video camera on the winglet, rear view mirror (yes this is possible) etc., but settled on the simplest system, a thermocouple in the exit air passing thru the cylinder fins. This is set up as an extra reading on our digital CHT scanner, and there is a high limit alarm that stops the scanner and flashes a red light. Incidently, you can also use a thermocouple in the air inlet and put OAT on your scanner. We believe that the chance of an engine fire is extremely remote, and that shutting off the fuel would put the fire out. We think that with a heat muff and heat duct, the occupants would certainly smell a fire if it occurred, even with the heat shut off. But if you need extra assurance, monitor the air temperature leaving the engine. BTW, before starting your engine on the ground, you should always turn on the fuel valve, give the engine a shot of prime, and pull the propellor through 3 blades (with the boost pump running). If you have a fuel leak, fuel will run out of the cowling before the engine starts. You can have a fuel leak from deteriorated flexible fuel lines, from a stuck float in a carburetor, and from a clogged diaphragm valve in the TB, and there are probably other sources as well, so you should always visually inspect the engine compartment with the pump running before starting. BTW this is one BIG advantage of the NACA scoop and parking nose down. If you have a fuel leak, it will be very obvious. We had one of the premium synthetic rubber braided stainless fuel lines (before we recommended switching to Teflon) and after it was about a year old, it suddenly started leaking like a sieve. We discovered it before starting the engine by following the procedure above. When we reported this to Aeroquip, we were told ours was the only complaint from this production run. Shortly thereafter, we learned that ours was the first complaint, and then they had a whole lot more. Regards, Nat -------- > From: David Domeier > To: gperry@usit.com > Cc: cozy_builders@canard.com > Subject: Re: COZY: Fuel Line Fittings > Date: Wednesday, August 19, 1998 9:29 PM > > Gregg, > > re ".what is the purpose of using steel fittings if they are > attaching to an aluminum gascolator and aluminum fuel lines? Am I > missing something here?" > > The original LEZ plan called for all aluminum in keeping with a > philosophy of building as light as possible. Somewhere along the way a > Long EZ had an inflight engine fire, the exact cause I think was never > determined, and shortly thereafter came a change to steel in the engine > compartment - flight controls and fuel fittings. > > The real reason for the change was probably more legal than > practical...I'm not convinced all steel is going to make that much > difference with an inflight engine fire. My feeling is a regular > inspection of the exhaust system is a better idea. If the fire does not > get started, aluminum is just fine. > > dd > > > From: "Nat Puffer" Subject: Re: COZY: Fuel Line Fittings Date: Thu, 20 Aug 1998 13:20:17 -0500 Dear Howard, When I shut my engine down, I do it by leaning the mixture all the way out and idle cut off. This insures that there will be no fuel left in or dripping from the TB or carb. When restarting, by giving it a shot of prime and then pulling thru 3 blades, you should have a charge ready to fire as soon as you engage the starter. In the Navy with radial engines it ensured that you didn't have a lower cylinder full of oil that would bust the cylinder or bend a rod when engaging the starter. The other thing it forces you to do, of course, is spend at least 30 seconds behind your airplane, which is enough time for fuel to gush out if you have a leak. When pulling the prop thru, I always make sure the mags are off, and I always have someone (usually Shirley) sitting in the front seat either nose down or feet on brakes ready to cut both the mixture and throttle. I should mention that the advantage of a pusher is that if you are pulling the prop through, your fingers will be on the trailing edge which is closest to you (you don't have to put your hand through the prop). If the engine should start, the airplane would try to move away from you and the prop blast would tend to push you away. 3 benefits of a pusher! My experience with braided Teflon fuel lines has been perfect to date. Regards, Nat ---------- > From: Howard Rogers > To: cozy_builders@canard.com > Subject: Re: COZY: Fuel Line Fittings > Date: Thursday, August 20, 1998 3:56 PM > > Nat, > Thank you for your good suggestions for an engine fire monitor. I > honestly had not given this any thought before, since in a tractor-mounted > engine a fire is usually pretty obvious! I will certainly be giving it a > lot of thought, now, though. If it happens, I want to know about it RIGHT > NOW! > > >BTW, before starting your engine on the ground, you should always turn on > >the fuel valve, give the engine a shot of prime, and pull the propellor > >through 3 blades (with the boost pump running). If you have a fuel leak, > >fuel will run out of the cowling before the engine starts. You can have a > >fuel leak from deteriorated flexible fuel lines, from a stuck float in a > >carburetor, and from a clogged diaphragm valve in the TB, and there are > >probably other sources as well, so you should always visually inspect the > >engine compartment with the pump running before starting. > > This is also an excellent suggestion, and it has the "ring" of some sage, > conventional wisdom. How is it, then, after 25 years of flying, I have > never heard it before? My only question is: why pull through several > blades? Am I missing something? I am aware that blade-pulling is > controversial, since accidents have happened with unintentionally "hot" > mags. There are aguments FOR, of course, like feeling for a very low > compression cylinder, for instance. I just don't get how the blade pulling > portion of the above technique will help reveal fuel leaks. > > >We had one of the premium synthetic rubber > >braided stainless fuel lines (before we recommended switching to Teflon) > >and after it was about a year old, it suddenly started leaking like a > >sieve. We discovered it before starting the engine by following the > >procedure above. When we reported this to Aeroquip, we were told ours was > >the only complaint from this production run. Shortly thereafter, we learned > >that ours was the first complaint, and then they had a whole lot more. > >Regards, > >Nat > > I remember this well, when it was reported in Canard Pusher. RAF had more > than one of these hoses spontaneously turn into sprinklers. I didn't know > yours was the first complaint. I remember thinking, at the time, that I > would stick with good old Aeroquip and fire sleeves. I have the mandrels, > and it isn't a big deal to change them out every five years during routine > maintenance. Cheap, too. What is your opinion of the teflon hoses, now > thay you have plenty of experience with them? > > --Howard Rogers, 650-926-4052 > hrogers@slac.stanford.edu > > From: gperry@usit.com Date: Sat, 22 Aug 1998 21:57:13 -0400 (EDT) Subject: COZY: Firewall fittings Hello everyone, I know everyone must be getting tired of my posts but I CANNOT make the fuel line connections work per Chapter 15 (Cozy Mark IV plans). With Steve Sharp's help, I now have a firewall bulkhead connector and can get INTO the gascolator. However, coming OUT of the gascolator is an 90 degree elbow connector followed by an impossibly short piece of aluminum tubing with a tight 90 degree bend. I'd love to know how to make this tight bend, then get a sleeve and nut and each end, then flare the ends and still be as short as the drawing shows! My flaring tool needs at least 5/8" of straight run to fit into the tool - and that's with the sleeve and nut pushed even further back. The drawing shows the bend starting at the end of the nut when it's TIGHTENED. The best I can do leaves the fuel pump above and to the left of where it should be on the drawing. The lack of directions in this chapter has been very frustrating. Can anyone tell me how they've solved this problem? Nat???? Gregg Perry Date: Sun, 23 Aug 1998 11:08:32 -0400 From: "Marc J. Zeitlin" Subject: Fwd: COZY: Firewall fittings Gregg Perry wrote; >......... Can anyone tell me how they've solved this problem? Nat???? While I haven't finished the tubing on the firewall yet, I've had exactly the same issues regarding small sections of bent tubing while working on the interior lines (3 times :-) ). I think the drawing(s) in Chapters 15 and 21 are representative, and not necessarily indicative of the EXACT lengths of tubing to use. I don't think there would be a problem with raising the fuel pump one inch, and moving it to the left one inch. This would allow more than enough tubing to be used in the 90 degree section, and wouldn't move the rest of the tubing so far as to make it interfere with anything else. I say this with no engine and no engine mount yet, so I may be completely off base, but I don't think so. Don't get hung up on exactly where the tubing runs - my impression is that if the plans don't tell you PRECISELY where to put something, it's probably not critical. While there are certainly sections of the plans that could be clearer, Nat's been pretty good about calling out critical to function areas. It's hard to imagine how moving the tubing a bit could hurt anything, as long as it doesn't interfere with something else. My $0.02. -- Marc J. Zeitlin                     marcz@burnside.ma.ultranet.com 3 Sweetbriar Way                  http://www.ultranet.com/~marcz Acton, MA  01720                 http://cozy.canard.com/ From: cdenk@ix.netcom.com Date: Tue, 25 Aug 1998 07:28:43 -0500 (CDT) Subject: Re: COZY: Firewall at NACA scoop On 08/24/98 21:23:42 you wrote: > >I have the stainless steel mounted on my firewall now but I'm not sure how >to close the gap at the NACA scoop. I'm considering just filling the gap >with RTV. Anyone with a better idea? Thanks. > >Paul Stowitts >Cozy Mark IV #200 > > I used 1 Part Polyurethane caulking (Vulken brand, but others including Tremco brand are available). Check with commercial building contractor. Not DIY or local hardware. The RTV is harmed by solvents including gasoline. The Polyurethane is not. Need to check chemical exposure data for product. Used this for entire perimeter of stainless firewall. I don't worry when oil or gas leak or washing engine.