Rotax 912iS Installation in Zenith Aircraft Information - Zenith Aircraft Builders and Flyers2024-03-29T05:54:31Zhttps://zenith.aero/forum/topics/rotax-912is-installation-in-zenith-aircraft-information?commentId=2606393%3AComment%3A262099&feed=yes&xn_auth=noI'm very happy to hear how cl…tag:zenith.aero,2015-12-15:2606393:Comment:4739362015-12-15T03:46:32.373Zdavid shraderhttps://zenith.aero/profile/davidshrader
I'm very happy to hear how close you are Joe. Can't wait to hear your first flight report. My legs were a little ruberie that day.<br />
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Dave
I'm very happy to hear how close you are Joe. Can't wait to hear your first flight report. My legs were a little ruberie that day.<br />
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Dave Very glad to hear your update…tag:zenith.aero,2015-12-14:2606393:Comment:4737972015-12-14T21:33:15.500ZGeoff Klestadthttps://zenith.aero/profile/GeoffKlestadt
<p>Very glad to hear your update Joe. My aircraft and the 912 iS has been neglected for nine months in favour of renovating the farm we moved to. I was starting to work on the wiring a few weeks ago but then managed to injure my index finger installing an engine in my boat, so i can't do much for another week!</p>
<p>Very glad to hear your update Joe. My aircraft and the 912 iS has been neglected for nine months in favour of renovating the farm we moved to. I was starting to work on the wiring a few weeks ago but then managed to injure my index finger installing an engine in my boat, so i can't do much for another week!</p> Well, it's been more than a y…tag:zenith.aero,2015-12-14:2606393:Comment:4738772015-12-14T21:15:33.234ZJoe Harringtonhttps://zenith.aero/profile/JoeHarrington
<p>Well, it's been more than a year since I have made the last update on the engine installation. I have got to be one of the world's slowest builders. I work on the plane almost everyday but just got to point of the first engine start. The 912iS Sport started right up as expected with zero issues (so far). I have posted the first start video here: <a href="https://www.youtube.com/watch?v=GwMD272MB7U">https://www.youtube.com/watch?v=GwMD272MB7U</a></p>
<p>Dave, one of our group of six, has had…</p>
<p>Well, it's been more than a year since I have made the last update on the engine installation. I have got to be one of the world's slowest builders. I work on the plane almost everyday but just got to point of the first engine start. The 912iS Sport started right up as expected with zero issues (so far). I have posted the first start video here: <a href="https://www.youtube.com/watch?v=GwMD272MB7U">https://www.youtube.com/watch?v=GwMD272MB7U</a></p>
<p>Dave, one of our group of six, has had his iS powered 750 up and flying for a few months already, and it runs beautifully without any issues. Dave says the 912iS is his most favourite part of his CH750. That is saying "something" considering he has a dual screen G3X with autopilot and many other bells and whistles on the great flying CH750. I am expecting the same with mine. The engine is just great and the firewall forward kit is very nicely designed. Rotech Research Canada (Canadian Rotax distributor) and Skytek Aircraft Services who developed the firewall forward kit both have proven to be premium quality vendors. If you are considering working with them, you will not go wrong.</p>
<p>I pretty much have the fuselage completed so the main job that I have to do now is to finish up a few details inside the wings and then install them. The doors and tail have been fitted (and removed to save space) so it should fly sometime next spring or early summer (I hope!) </p> Joe, don't worry too much, th…tag:zenith.aero,2014-11-18:2606393:Comment:3930262014-11-18T23:51:26.639ZGeoff Klestadthttps://zenith.aero/profile/GeoffKlestadt
Joe, don't worry too much, the STOL bird is not as tail heavy. I'm out of Australia at the moment so I can't send you the spreadsheet or a copy of the email from Keith.<br></br>
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The mount may be a fraction short for the STOL 750 but Keith told me it's OK provided you are mindful to keep weight forward including adding the Three washers to push the engine forward a little. He said that a fully primed and painted aircraft, with autopilot servos, that he built was right on the rear limit at…
Joe, don't worry too much, the STOL bird is not as tail heavy. I'm out of Australia at the moment so I can't send you the spreadsheet or a copy of the email from Keith.<br/>
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The mount may be a fraction short for the STOL 750 but Keith told me it's OK provided you are mindful to keep weight forward including adding the Three washers to push the engine forward a little. He said that a fully primed and painted aircraft, with autopilot servos, that he built was right on the rear limit at MTOW. My calculation showed that adding the airmaster puts an extra ten pounds in front and brings the CG about an inch in under those conditions.<br/>
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The CRUZER? Thats a different kettle of fish... Joe, I think overall the CruZ…tag:zenith.aero,2014-11-18:2606393:Comment:3930962014-11-18T16:20:59.026ZDon Morriseyhttps://zenith.aero/profile/DonaldMorrisey
<p>Joe, I think overall the CruZer is a heavier airplane than the STOL. That's an interesting point about how a 1" engine mount extension affects so much else...the proverbial consequential damages. The problem here is we have the tail wagging the dog. ALL the FWF components were fabricated to fit an engine mount that is too short, so we're trying to fix the symptoms and not the problem. I think Zenith and Skytek need to get out in front of this thing....by all accounts the combination of…</p>
<p>Joe, I think overall the CruZer is a heavier airplane than the STOL. That's an interesting point about how a 1" engine mount extension affects so much else...the proverbial consequential damages. The problem here is we have the tail wagging the dog. ALL the FWF components were fabricated to fit an engine mount that is too short, so we're trying to fix the symptoms and not the problem. I think Zenith and Skytek need to get out in front of this thing....by all accounts the combination of the STOL and/or CruZer with a Rotax 912is, is showing to be very popular. Better to bite the bullet and get it done right. Maybe there's another solution but I'm not smart enough to know what it is.</p>
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<p>If I understand you correctly on the prop extension, you are adding a spacer of approximately 2 1/4" between the engine and the prop so it sounds like there is room in the cowl to accommodate this extension?? Why do you need the extension? The heavier tire and tool box are also creative ways to get more nose heavy. I guess if all else failed some lead weights could be added to the tip of the cowl?? Just thinking out loud here. The overriding question though is when does the real problem get solved??</p> The W&B for the OWW is no…tag:zenith.aero,2014-11-18:2606393:Comment:3930842014-11-18T03:42:33.391ZJoe Harringtonhttps://zenith.aero/profile/JoeHarrington
<p>The W&B for the OWW is not the best news (and is probably driving Zenair and Skytek crazy...). It might not be such a big deal if it was only the engine to worry about, but it affects many other things such as the cowl, fuel and oil lines, etc. The cowl is just barely long enough as it is so if an inch is added to the mount , the cowl may have to be extended. I am using a 60 mm prop extension, so maybe the engine could come forward some and not interfere with the cowl.</p>
<p>I still…</p>
<p>The W&B for the OWW is not the best news (and is probably driving Zenair and Skytek crazy...). It might not be such a big deal if it was only the engine to worry about, but it affects many other things such as the cowl, fuel and oil lines, etc. The cowl is just barely long enough as it is so if an inch is added to the mount , the cowl may have to be extended. I am using a 60 mm prop extension, so maybe the engine could come forward some and not interfere with the cowl.</p>
<p>I still have the hope that I might be okay. I have been mounting everything that I can as far forward as possible such as the elt which I mounted under the seat. I have auto pilot servos which are mounted much further forward than the OWW. Just looking at the Cruzer, to me it looks like the tail pieces are heavier than the STOL. I am also planning to use an 8.00 X 6 aircraft tire on the nosewheel (a la Walt Snyder) which should help quite a bit. Another idea that I have is fabricating a tool box and installing it forward of the firewall. I always fly with some tools and the way I have configured my fwf, I will have the room to rivet a box onto the firewall shelf (stiffener).</p>
<p>And Geoff, if I understand correctly, they (Zenair/Skytek) were going to supply us with the eyebrow NACA ducts at some point in the near future and we could install them ourselves if we are so inclined. I think will install them but living in the great white north means they might not be so critical. And yes, I have worked a bit to get my cowl to fit together. The left (pilot) side requires the most work. I sanded about 5 mm off the edge of the top cowl near the centre.</p>
<p>Building airplanes is not for the impatient...</p> I just received the W&B i…tag:zenith.aero,2014-11-17:2606393:Comment:3926402014-11-17T20:17:07.115ZDon Morriseyhttps://zenith.aero/profile/DonaldMorrisey
<p>I just received the W&B info for the OWW...definitely out of the aft range at full load...I have no idea if the STOL version suffers the same problem. Posted here:<a href="http://www.zenith.aero/group/750-cruzer/forum/topics/one-week-wonder-w-b-here-it-is">http://www.zenith.aero/group/750-cruzer/forum/topics/one-week-wonder-w-b-here-it-is</a></p>
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<p>I would say that for those wanting a CruZer/912is combination that <span style="text-decoration: underline;"><strong>Zenith has to…</strong></span></p>
<p>I just received the W&B info for the OWW...definitely out of the aft range at full load...I have no idea if the STOL version suffers the same problem. Posted here:<a href="http://www.zenith.aero/group/750-cruzer/forum/topics/one-week-wonder-w-b-here-it-is">http://www.zenith.aero/group/750-cruzer/forum/topics/one-week-wonder-w-b-here-it-is</a></p>
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<p>I would say that for those wanting a CruZer/912is combination that <span style="text-decoration: underline;"><strong>Zenith has to come up with a different engine mount.</strong></span>...this is clearly well out of range even using 170 lbs for pilot and passenger.</p>
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<p>A heavy prop up front would definitely help but assuming an extra 12 pounds or so on an Airmaster, still leaves an issue with the aft range. An additional 16 pounds would be needed on the nosewheel to get within range and then we'd have to get down to 170 lbs to make that work.</p> I agree 100% with Joe, Skytek…tag:zenith.aero,2014-11-17:2606393:Comment:3928342014-11-17T09:41:28.834ZGeoff Klestadthttps://zenith.aero/profile/GeoffKlestadt
I agree 100% with Joe, Skytek are fantastic to work with and everything fits as advertised! Keith and Darian are great to talk to and a mine of information. I am something like the same state of installation as Joe. I have also received an Airmaster propeller which is so beautiful I want to hang it on the wall as a work of art. Keith reckons the standard 750 will just balance at the rear of the CG with the fixed pitch prop and full load. The airmaster should help - thats also what the Three…
I agree 100% with Joe, Skytek are fantastic to work with and everything fits as advertised! Keith and Darian are great to talk to and a mine of information. I am something like the same state of installation as Joe. I have also received an Airmaster propeller which is so beautiful I want to hang it on the wall as a work of art. Keith reckons the standard 750 will just balance at the rear of the CG with the fixed pitch prop and full load. The airmaster should help - thats also what the Three washers on each engine mount bolt are for.<br />
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I'mm using the SKytek fuel system from the wing roots down. My wings are finished with 3/8 braided ss and teflon lines and I cant replace the vent line without reskinning but I am replacing he fuel inlet line with bigger stuff and following the skytek design in braided Stainless and teflon Goodridge convoluted hose which is delightfully easy to work with and flows well too and with a very small minimum bend radius.<br />
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A few words, I have spent a month on the cowl and I still haven't got a straight join between top and bottom. I am using the quarter turn quick release fittings and it all has to be "tuned" just right to make it neat - I've given up. I've also added the twp 3 inch vents on top of the nose that now seem to be deleted. Keith says that they cool the electronics at taxi speeds but aren't needed in flight. Anyway they are cheap to buy and fit which I've done and also the engine air filter intake is easy when you use West System epoxy like me.<br />
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Bad images below: Joe thx for the info on the c…tag:zenith.aero,2014-11-16:2606393:Comment:3927032014-11-16T23:08:09.298ZDon Morriseyhttps://zenith.aero/profile/DonaldMorrisey
Joe thx for the info on the course.<br />
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What are your plans to overcome the Engine mount/W&B issue? Doesn't soumd like you're going with a heavy prop so your issue would be useful load??<br />
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This could prove to be a big issue for builders...it's amazing how, what should be a minor calculation/fabrication issue can have such impact on the planes we build...also not exactly in your control.<br />
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In my case Roger has indicated that Charlie Becker at the EAA, has the OWW W&B info and I have asked…
Joe thx for the info on the course.<br />
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What are your plans to overcome the Engine mount/W&B issue? Doesn't soumd like you're going with a heavy prop so your issue would be useful load??<br />
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This could prove to be a big issue for builders...it's amazing how, what should be a minor calculation/fabrication issue can have such impact on the planes we build...also not exactly in your control.<br />
<br />
In my case Roger has indicated that Charlie Becker at the EAA, has the OWW W&B info and I have asked Charlie to provide it since that is exactly what I'm building with the exception of the Airmaster prop. All things being equal I'd probably prefer the Catto prop if it is as good as advertised and save myself $5000. I'll share the OWW, W&B info as soon as I get it. Don, I bought the engine moun…tag:zenith.aero,2014-11-16:2606393:Comment:3926912014-11-16T19:16:08.500ZJoe Harringtonhttps://zenith.aero/profile/JoeHarrington
<p>Don, I bought the engine mount from Zenith in Mexico, MO. I believe they fabricated it there. I have been led to believe that the engine mount is a little short for the iS and a normal config’ed aircraft/load will have the w&b near the rear of the c of g. The weight of the Airmaster should work to your benefit. Not sure if you will be out the front of the c of g if you have no baggage, though. I suspect as all these configurations mature, ZAC will have more tangible info…</p>
<p>Don, I bought the engine mount from Zenith in Mexico, MO. I believe they fabricated it there. I have been led to believe that the engine mount is a little short for the iS and a normal config’ed aircraft/load will have the w&b near the rear of the c of g. The weight of the Airmaster should work to your benefit. Not sure if you will be out the front of the c of g if you have no baggage, though. I suspect as all these configurations mature, ZAC will have more tangible info available.</p>
<p>The course that I took was the Rotax accredited 912iS Sport Service course which is the most basic course for this engine. I think many of the Rotax Service Centres are set up to teach courses which give participants an “Independent Rotax Maintenance Technician” (iRMT) designation. I think the course that I took was the first, or at least one of the first, iS service courses to be held for someone other than a Rotax dealer. Even though I took it at Rotech Research (North and South American distributor for Rotax Certified Aircraft Engines), I think you may be able to receive the same course at Service Centres like Lockwood. You can find more info here: <a href="http://www.rotax-owner.com/education-5/4-stroke-training" target="_blank">http://www.rotax-owner.com/education-5/4-stroke-training</a></p>
<p>Regards,</p>
<p>Joe</p>