---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Fri 09/02/05: 16 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:26 AM - Official Usage Guideline [Please Read] [Monthly Posting] (dralle@matronics.com) 2. 07:44 AM - Re: Zenith-List Digest: 25 Msgs - 09/01/05 (Gig Giacona) 3. 08:58 AM - Valve Adjustment (N5SL) 4. 09:08 AM - Re: XL Specification for Vne, and Rotax vs Jabiru Horsepower. (Leo Corbalis) 5. 09:53 AM - Re: Valve Adjustment (bryanmmartin@comcast.net) 6. 10:31 AM - Re: Valve Adjustment (Randy Stout) 7. 10:45 AM - Re: 601XL Jab 3300 Carb Econo Tuning Kit (japhillipsga@aol.com) 8. 11:23 AM - Re: Valve Adjustment (N5SL) 9. 11:36 AM - Re: Valve Adjustment (Paul Moore) 10. 11:53 AM - Re: XL Specification for Vne, and Rotax vs Jabiru (Jeff Davidson) 11. 11:59 AM - Re: Valve Adjustment (Randy Stout) 12. 12:07 PM - Re: Valve Adjustment (N5SL) 13. 12:33 PM - Re: Valve Adjustment (Bill Cardell) 14. 01:40 PM - Re: XL Specification for Vne, and Rotax vs Jabiru Horsepower. (Hal Rozema) 15. 05:28 PM - Engine mounts (Dabusmith@aol.com) 16. 08:25 PM - Re: XL Specification for Vne, and Rotax vs Jabiru Horsepower. (Chris Boultinghouse) ________________________________ Message 1 _____________________________________ Time: 12:26:41 AM PST US From: dralle@matronics.com Subject: Zenith-List: Official Usage Guideline [Please Read] [Monthly Posting] DNA: do not archive --> Zenith-List message posted by: dralle@matronics.com Dear Lister, Please read over the Zenith-List Usage Guidelines below. The complete Zenith-List FAQ including these Usage Guidelines can be found at the following URL: http://www.matronics.com/FAQs/Zenith-List.FAQ.html Thank you, Matt Dralle Matronics Email List Administrator ****************************************************************************** Zenith-List Usage Guidelines ****************************************************************************** The following details the official Usage Guidelines for the Zenith-List. You are encouraged to read it carefully, and to abide by the rules therein. Failure to use the Zenith-List in the manner described below may result in the removal of the subscribers from the List. Zenith-List Policy Statement The purpose of the Zenith-List is to provide a forum of discussion for things related to this particular discussion group. The List's goals are to serve as an information resource to its members; to deliver high-quality content; to provide moral support; to foster camaraderie among its members; and to support safe operation. Reaching these goals requires the participation and cooperation of each and every member of the List. To this end, the following guidelines have been established: - Please keep all posts related to the List at some level. Do not submit posts concerning computer viruses, urban legends, random humor, long lost buddies' phone numbers, etc. etc. - THINK carefully before you write. Ask yourself if your post will be relevant to everyone. 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DO use lines from the original post to help "tune in" the reader to the topic at hand, but be selective. The impact that quoting the entire original post has on the size of the archive can not be overstated! - When the poster asks you to respond to him/her personally, DO NOT then go ahead and reply to the List. Be aware that clicking the "reply" button on your mail package does not necessarily send your response to the original poster. You might have to actively address your response with the original poster's email address. - DO NOT use the List to respond to a post unless you have something to add that is relevant and has a broad appeal. "Way to go!", "I agree", and "Congratulations" are all responses that are better sent to the original poster directly, rather than to the List at large. - When responding to others' posts, avoid the feeling that you need to comment on every last point in their posts, unless you can truly contribute something valuable. - Feel free to disagree with other viewpoints, BUT keep your tone polite and respectful. Don't make snide comments, personally attack other listers, or take the moral high ground on an obviously controversial issue. This will only cause a pointless debate that will hurt feelings, waste bandwidth and resolve nothing. ------- [This is an automated posting.] ________________________________ Message 2 _____________________________________ Time: 07:44:20 AM PST US From: "Gig Giacona" Subject: Zenith-List: Re: Zenith-List Digest: 25 Msgs - 09/01/05 --> Zenith-List message posted by: "Gig Giacona" Lance, I hate to be the one to break it to you but unless I'm very much mistaken you won't be able to get it ELSA approved. The ELSA plans were the last set and there are changes from the ones you built your plane by. I'm in the same boat. They are significant enough that Linda at Zenith talked me out of buying a new set. Time: 02:58:47 PM PST US Subject: Zenith-List: Anyone registered their ZODIAC as an ELSA yet? From: "Lance Gingell" --> Zenith-List message posted by: "Lance Gingell" List, I'm really close to getting my XL airborne, and I'm trying to get a DAR to come and inspect my airplane. Has anyone certified their ZODIAC as an ELSA yet? I was originally thinking of getting it certified as an "Experimental Amateur Built". This would be easier to find a DAR etc. but I've since learnt that if I get an airworthiness certificate/inspection as Experimental Light Sport, that the following applies: 1. Anyone who does a 16 hour repairman course can maintain the airplane if I sell it to them. (slight downside - I must take the 16 hour course too - which will be good anyway, so I'm happy) 2. The phase I flight test limitation is ONLY 5 HOURS ... this is better than 40 for ExAB! 3. I must get a Light Sport certified DAR. This is the tricky one. The guy that is close to me is still waiting for the FAA to say "go forth and inspect". Apparently this could be any day (or month) from now. There don't appear to be any downsides to doing ELSA vs ExAB as far as I can see. IFR is no problem for example (if airplane and pilot are capable). Anyone managed to get an ELSA airworthiness inspection scheduled/completed? ________________________________ Message 3 _____________________________________ Time: 08:58:17 AM PST US From: N5SL Subject: Zenith-List: Valve Adjustment --> Zenith-List message posted by: N5SL Fellow Engine Builders: Yesterday I began installing my rocker arms, grooved balls, etc. I have William's video, but there's one area I'm a little fuzzy about. I'm not sure when to start the process on each valve. I'm assuming the only thing that matters is that the pushrod is in it's lowest position on the camshaft. This is what I did: 1. I rotated the engine (on it's nose bolted to the workbench) until the lifter to be adjusted was all the way down and the adjacent lifter was up. 2. I installed the rocker arm and tightened the nut down until I could no longer twist the pushrod easily by hand. (tiny hole facing rocker) 3. I then rotated the engine a few more times to clean the lube off the cam lobe, then re-aligned the lifter so it was all the way down and the next one was up. 4. I then re-checked the twisting of the pushrod to make sure it was tightened down just touching the rocker arm to the pushrod to the lifter to the camshaft lobe. 5. Finally I tightened the nut 3/4 turn and called it good. Can anybody tell me if I did this correctly. It is easy enough to re-do them and I only have one side done anyway. Thanks in advance, Scott Laughlin 601XL/Corvair 99% complete with an overwhelming list of things to do. http://www.cooknwithgas.com/ --------------------------------- ________________________________ Message 4 _____________________________________ Time: 09:08:25 AM PST US From: "Leo Corbalis" Subject: Re: Zenith-List: XL Specification for Vne, and Rotax vs Jabiru Horsepower. --> Zenith-List message posted by: "Leo Corbalis" 3300 rpm is not a very useful speed range for available propellers. Most props are limited to lower rpm. centrifugal force increases as the square of the rpm causing prop blades to leave their happy hub and fly off into the great beyond. Yes I know about the racers that crank 4000 rpm out of a C-90. They are engineered to do it. Leo Corbalis ----- Original Message ----- From: Subject: Re: Zenith-List: XL Specification for Vne, and Rotax vs Jabiru Horsepower. > --> Zenith-List message posted by: bryanmmartin@comcast.net > > Vne is defined as 90% of the maximum speed at which the aircraft has been > tested at with no signs of flutter or other structural failure. In order > to claim that a certain speed is the Vne you must actually test fly the > airplane at 111% of this speed and determine that it does not show signs > of flutter or failure. > > I don't know where the 140 knots you mention came from. The information > I recieved from ZAC for the XL is that 180mph is Vne. I flew my airplane > at 200mph during phase I testing to verify this. I suspect that this speed > is a conservative design parameter that takes into account less than > perfect construction by individual builders. A very well built plane could > probably safely exceed this speed by a significant margin, but I wouldn't > recommend it. > > The Rotax 912s is rated at 100hp for 5 minutes and 95hp continuously at > 5500 RPM. According to Jabiru, the Jabiru 3300 is rated at 120hp at 3300 > RPM continuous, but you will probably never see 3300 RPM in practice, > 110hp is a more realistic expectation. > > The Rotax produces a relatively high power for its size by running at a > high RPM and a high compression ratio (10.5:1) and using a reduction gear > to drive the propeller. The high compression ratio requires the use of > high octane gas. The jabiru is a direct drive engine with a lower > compression ratio (8:1) so it needs to have a larger displacement to > produce the same power as the Rotax. Because of the lower compression > ratio, the Jabiru could probably run on lower octane gas even though the > manufacturer specifies 100 octane avgas. > > -- > Bryan Martin > N61BM, CH 601 XL, Stratus Subaru. > do not archive > > >> --> Zenith-List message posted by: Paul Mulwitz >> >> >> Vne on my drawing front page shows 140 kts, but on the ZAC web page >> it shows 180 mph. This leaves me realizing I don't really know how >> this number is derived. Is it a design goal like load factors or is >> it an arbitrary number similar to maximum gross weight? >> >> After talking to Pete and reviewing some details shown on the ZAC web >> page, I finally have a clue about why the Jabiru performance numbers >> are so much better than the Rotax numbers even though both engines >> show similar numbers for horsepower. First, it seems the Jabiru >> horsepower number is low. According to Pete the new 3300 engines >> produce around 130 horsepower. They are constantly being improved, >> and the reported numbers tend to be lower than the actual >> ones. Also, the displacement of the 3300 is 3.3 liters while the >> Rotax is around 1.3. ZAC shows 100 HP for the Rotax and 110 for the >> Jabiru, but the vendor documents show more like 95 for the Rotax and >> 130 for the Jabiru. No wonder the Jabiru works better. > > > ________________________________ Message 5 _____________________________________ Time: 09:53:55 AM PST US From: bryanmmartin@comcast.net Subject: Re: Zenith-List: Valve Adjustment --> Zenith-List message posted by: bryanmmartin@comcast.net Usually, valve clearances are set with the piston at TDC on the compression stroke. At that point, both valves will be closed and at the lowest point on the cam. The usual practice is to pull the spark plug and look in the hole to see the piston at TDC with the distributor rotor pointing at that spark tower and then set both valves. -- Bryan Martin N61BM, CH 601 XL, Stratus Subaru. do not archive > --> Zenith-List message posted by: N5SL > > Fellow Engine Builders: > > Yesterday I began installing my rocker arms, grooved balls, etc. I have > William's video, but there's one area I'm a little fuzzy about. I'm not sure > when to start the process on each valve. ________________________________ Message 6 _____________________________________ Time: 10:31:08 AM PST US From: "Randy Stout" Subject: RE: Zenith-List: Valve Adjustment --> Zenith-List message posted by: "Randy Stout" Scott I just rebuilt mine (again). I took William's videos out to the hangar and set up a TV/VCR and assembled it as the video was playing. I liked the way he bolted the engine to the table on it's nose with the top and bottom open. You can tell what's going on better that way. I couldn't get a consistent feel using the twist between the fingers method. I pushed the rocker against the pushrod, not too hard as you can depress the lifter, while looking between the lifter and valve. A light on the opposite side helps. Turn the nut until the light going between the two parts disappears. Maybe rock the rocker back and forth a few times to make sure you have it right. Then add 3/4 turn. It seems to have worked. I've made 4 flights since and am getting between 115 and 120 mph top speed on a hot Texas day. Before the rebuild, I could only get 115 mph under the best conditions. Usually closer to 107 mph. Remember this is a HD and 115-120 is still not the speed ZAC promised us, but it is good. One more thing...Be careful to make sure you have the pushrod in the dimple of the lifter. It's real easy to get it on the edge of the lifter. Then one day you'll be out flying and wondering why your engine is running a bit slower today. Don't ask how I know. Randy Stout n282rs"at"earthlink.net www.geocities.com/r5t0ut21 > [Original Message] > From: N5SL > To: > Date: 9/2/2005 10:56:58 AM > Subject: Zenith-List: Valve Adjustment > > --> Zenith-List message posted by: N5SL > > Fellow Engine Builders: > > Yesterday I began installing my rocker arms, grooved balls, etc. I have William's video, but there's one area I'm a little fuzzy about. I'm not sure when to start the process on each valve. I'm assuming the only thing that matters is that the pushrod is in it's lowest position on the camshaft. This is what I did: > > 1. I rotated the engine (on it's nose bolted to the workbench) until the lifter to be adjusted was all the way down and the adjacent lifter was up. > 2. I installed the rocker arm and tightened the nut down until I could no longer twist the pushrod easily by hand. (tiny hole facing rocker) > 3. I then rotated the engine a few more times to clean the lube off the cam lobe, then re-aligned the lifter so it was all the way down and the next one was up. > 4. I then re-checked the twisting of the pushrod to make sure it was tightened down just touching the rocker arm to the pushrod to the lifter to the camshaft lobe. > 5. Finally I tightened the nut 3/4 turn and called it good. > > Can anybody tell me if I did this correctly. It is easy enough to re-do them and I only have one side done anyway. > > Thanks in advance, > > Scott Laughlin > 601XL/Corvair > 99% complete with an overwhelming list of things to do. > http://www.cooknwithgas.com/ > > > > --------------------------------- > > ________________________________ Message 7 _____________________________________ Time: 10:45:48 AM PST US From: japhillipsga@aol.com Subject: Re: Zenith-List: 601XL Jab 3300 Carb Econo Tuning Kit --> Zenith-List message posted by: japhillipsga@aol.com Rick, great to hear from you ! 117 hours, I envy you, I have only 10. Tony sent me his copy of instructions, so thanks anyway. I still need to find a 1.6mm bit and so the effort goes on. When I get around to taking some photos I will send you one. best regards, Bill -----Original Message----- From: Rick Tedford Subject: Re: Zenith-List: 601XL Jab 3300 Carb Econo Tuning Kit --> Zenith-List message posted by: "Rick Tedford" Hello Bill : My carb kit came with a 1.6 MM drill bit . It was used to drill out an air supply inlet at the mouth of the carb . I believe it was located on the right side of the carb venturi . My instructions are squirreled away in my shop but I think Pete can clarify the procedure better than I . If you are talking to Pete K , ask him if he will be holding a maintenance seminar in October . He mentioned he was , but the date was not set . I would like to attend same and hopefully there is a spot open for me I have 117 hours and am counting Best regards Rick Tedford ----- Original Message ----- From: Subject: Zenith-List: 601XL Jab 3300 Carb Econo Tuning Kit > --> Zenith-List message posted by: JAPhillipsGA@aol.com > > Dear Thread Friends, well my Econo Tuning Kit was waiting for me when I > arrived home this evening. That was really quick delivery cause I think I > placed > the call to Jab Tuesday pm. Kudos' to Jab of Tennessee ! In it I received > 3 > brass jet looking things and a jet needle. Along with it came the Jab > Service > Letter. Five and ahalf pages about the benefits of having the kit in my > carburetor and the improved level of performance I should achieve with it > and the > standard with which to measure that performance, but almost nil about how > to > actually install it. Also, there's a single sentence about drilling out > the inlet > aperture to 1.6 mm, but is that one of the three new parts or one that's > already > on the carb. Maybe I'm missing a page or two in my letter. Did anybody > get a > different service letter with more better instructions in it ? This seems > like a fairly important modification, with your basic life and death > possible > outcomes and repercussions for screwing it up, so actually having steps to > follow > in installing it seems reasonably important as well. I really hate to have > to > ask Pete, especially if this is something so simple that anybody and > everybody else knows the inner workings of all the little bits and pieces > inside the > standard Bing, but I thought I would ask you fine folks first, Hope to > hear > from someone, Best regards, Bill of Georgia > > > ________________________________ Message 8 _____________________________________ Time: 11:23:53 AM PST US From: N5SL Subject: RE: Zenith-List: Valve Adjustment --> Zenith-List message posted by: N5SL Randy thanks so much. I just noticed I posted this on the Zenith list and not the Corvaircraft list! Geez I need to get my lists straight. It means a lot coming from a guy who is flying so thanks for the email. Scott Laughlin Randy Stout wrote: --> Zenith-List message posted by: "Randy Stout" Scott I just rebuilt mine (again). --------------------------------- ________________________________ Message 9 _____________________________________ Time: 11:36:35 AM PST US From: "Paul Moore" Subject: RE: Zenith-List: Valve Adjustment --> Zenith-List message posted by: "Paul Moore" I wouldn't want to minimize the importance of getting this right, but it's really much less critical than using a light to see when the rocker touches the pushrod. It's the standard Chevy hydraulic lifter adjustment procedure. Generally, hydraulic lifters have right at 2 turns of travel from when the pushrod starts pushing the piston down until it bottoms out. Most car manuals will tell you to run them in the middle - 1 full turn. Most hot rodders will run them in 1/4 turn so when they top out on the RPM range, the valves won't be held open by lifters that are pumped full of oil and don't have time to bleed off at those higher revs. Too loose and they'll still work, but they'll rattle and make ticking noises. Mostly, you just want to make sure the lifter is not sitting on the cam lobe crest or side ramps for the valve you are adjusting - whatever way is easiest for you is fine, top dead center, with the opposite (intake/exhaust for one cylinder) valve pushed wide open, doesn't matter. Tighten the nut until the rocker arm has no obvious play on either the valve cap or the pushrod (it will still rock slightly side to side but not end to end unless you force it), then run it down 1/2 to 3/4 turn. You can do it while the engine is running by backing off the nut until the rocker starts rattling, then back in just enough to stop the noise, and finally run it in your 3/4 turn. Do each one in turn - all the while getting a nice oil bath! Paul XL - O200 > [Original Message] William's video, but there's one area I'm a little fuzzy about. I'm not sure when to start the process on each valve. I'm assuming the only thing that matters is that the pushrod is in it's lowest position on the camshaft.... Do Not Archive ________________________________ Message 10 ____________________________________ Time: 11:53:04 AM PST US From: Jeff Davidson Subject: Re: Zenith-List: XL Specification for Vne, and Rotax vs Jabiru Horsepower. --> Zenith-List message posted by: Jeff Davidson 3300 rpm is not a very useful speed range for available propellers. Most props are limited to lower rpm. centrifugal force increases as the square of the rpm causing prop blades to leave their happy hub and fly off into the great beyond. Yes I know about the racers that crank 4000 rpm out of a C-90. They are engineered to do it. .............. At the Jabiru workshop the typical practical RPM setting for the Jabiru 3300A was given as 2800 RPM. That should be about 105 HP or so. Jeff Davidson ________________________________ Message 11 ____________________________________ Time: 11:59:31 AM PST US From: "Randy Stout" Subject: RE: Zenith-List: Valve Adjustment --> Zenith-List message posted by: "Randy Stout" I tried this once and it is very difficult to hear the rattle with a prop just inches from your ear. Randy Stout n282rs"at"earthlink.net www.geocities.com/r5t0ut21 > > You can do it while the engine is running by backing off the nut until the > rocker starts rattling, then back in just enough to stop the noise, and > finally run it in your 3/4 turn. Do each one in turn - all the while getting > a nice oil bath! > ________________________________ Message 12 ____________________________________ Time: 12:07:16 PM PST US From: N5SL Subject: Re: Zenith-List: Valve Adjustment --> Zenith-List message posted by: N5SL Thank you Martin. The cool thing about the corvair is that you can mount it on the workbench like this: http://www.cooknwithgas.com/8_28_05_Engine.JPG And you can turn the engine while the pistons go up and down. An added bonus is that you can see the hydr. lifters (with the oil pan off) and when they are up or down to determine when the valve is closed all the way. Thanks for the email - this dialog has helped me think through the logic. If you can convince me that a closed valve at TDC on the compression stroke is any different from a fully closed valve anywhere else in the cycle (a closed intake valve on the exhaust stroke for example), I may have to re-think this. Scott Laughlin bryanmmartin@comcast.net wrote: --> Zenith-List message posted by: bryanmmartin@comcast.net Usually, valve clearances are set with the piston at TDC --------------------------------- ________________________________ Message 13 ____________________________________ Time: 12:33:47 PM PST US Subject: RE: Zenith-List: Valve Adjustment From: "Bill Cardell" --> Zenith-List message posted by: "Bill Cardell" There shouldn't be "much" difference, but when a cylinder is at TDC compression it will be on the absolute heel of the cam. At any other point, the valve may be closed, but the lifter may be partway up the ramp, in the section that first takes up the slack. Bill Cardell (TurboDog's Dad) www.flyinmiata.com 1-800-FLY-MX5S tech 970-242-3800 -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of N5SL Subject: Re: Zenith-List: Valve Adjustment --> Zenith-List message posted by: N5SL Thank you Martin. The cool thing about the corvair is that you can mount it on the workbench like this: http://www.cooknwithgas.com/8_28_05_Engine.JPG And you can turn the engine while the pistons go up and down. An added bonus is that you can see the hydr. lifters (with the oil pan off) and when they are up or down to determine when the valve is closed all the way. Thanks for the email - this dialog has helped me think through the logic. If you can convince me that a closed valve at TDC on the compression stroke is any different from a fully closed valve anywhere else in the cycle (a closed intake valve on the exhaust stroke for example), I may have to re-think this. Scott Laughlin bryanmmartin@comcast.net wrote: --> Zenith-List message posted by: bryanmmartin@comcast.net Usually, valve clearances are set with the piston at TDC --------------------------------- ________________________________ Message 14 ____________________________________ Time: 01:40:20 PM PST US From: Hal Rozema Subject: Re: Zenith-List: XL Specification for Vne, and Rotax vs Jabiru Horsepower. --> Zenith-List message posted by: Hal Rozema Just a thought. Propellors don't care about horse power... It is torque they require.. If memory serves 2800 rpm is about the peak torque on a 3300 Just a thought. Hal Rozema ch701/3300 SuperSTOL Phoenix ThePlaneFolks.Net Jeff Davidson wrote: >--> Zenith-List message posted by: Jeff Davidson > > >3300 rpm is not a very useful speed range for available propellers. Most >props are limited to lower rpm. centrifugal force increases as the square of >the rpm causing prop blades to leave their happy hub and fly off into the >great beyond. Yes I know about the racers that crank 4000 rpm out of a C-90. >They are engineered to do it. .............. > >At the Jabiru workshop the typical practical RPM setting for the Jabiru 3300A was given as 2800 RPM. That should be about 105 HP or so. > >Jeff Davidson > > > > ________________________________ Message 15 ____________________________________ Time: 05:28:05 PM PST US From: Dabusmith@aol.com Subject: Zenith-List: Engine mounts --> Zenith-List message posted by: Dabusmith@aol.com I am planning to replace my rubber engine mounts on my 912ULS/701. Anyone know of a good source? Thanks Dave Smith Graham WA. ________________________________ Message 16 ____________________________________ Time: 08:25:41 PM PST US From: "Chris Boultinghouse" Subject: RE: Zenith-List: XL Specification for Vne, and Rotax vs Jabiru Horsepower. --> Zenith-List message posted by: "Chris Boultinghouse" Leo, I think you'll get some disagreement from the dozens of Sonex drivers out there who happily spin their Sensenich and Prince props right up to (and sometimes beyond) 3300 rpm! Sure seems to be a useful enough rpm range to spank the living daylights (speed-wise) out of any Zodiac on the planet. And they don't seem to be having any issues with blades leaving their happy hub either! Just a thought. : ) -Chris DO NOT ARCHIVE > -----Original Message----- > From: owner-zenith-list-server@matronics.com > [mailto:owner-zenith-list-server@matronics.com]On Behalf Of Leo Corbalis > Sent: Friday, September 02, 2005 11:08 AM > To: zenith-list@matronics.com > Subject: Re: Zenith-List: XL Specification for Vne, and Rotax vs Jabiru > Horsepower. > > > --> Zenith-List message posted by: "Leo Corbalis" > > > 3300 rpm is not a very useful speed range for available propellers. Most > props are limited to lower rpm. centrifugal force increases as > the square of > the rpm causing prop blades to leave their happy hub and fly off into the > great beyond. Yes I know about the racers that crank 4000 rpm out > of a C-90. > They are engineered to do it. > > Leo Corbalis