Rotax Engine Forum - Zenith Aircraft Builders and Flyers2024-03-28T21:23:05Zhttps://zenith.aero/forum/categories/rotax-engine-forum/listForCategory?categoryId=2606393%3ACategory%3A626737&feed=yes&xn_auth=noRotax 912s mountingtag:zenith.aero,2024-02-25:2606393:Topic:9256062024-02-25T20:58:16.081ZRui Melohttps://zenith.aero/profile/RuiMelo
<p>I am building a zenair 601 xl with a rotax 912 s , by scratch.</p>
<p></p>
<p>The plans that I have for the engine mount does not show the alignment of the engine in relation to the reference line , the upper longeron.</p>
<p></p>
<p>Shall I alignh the reference line with the cranckshaft or the center of the propeller?</p>
<p>Sorry for my bad english</p>
<p></p>
<p>Thank you for the help</p>
<p></p>
<p>Rui Melo</p>
<p>I am building a zenair 601 xl with a rotax 912 s , by scratch.</p>
<p></p>
<p>The plans that I have for the engine mount does not show the alignment of the engine in relation to the reference line , the upper longeron.</p>
<p></p>
<p>Shall I alignh the reference line with the cranckshaft or the center of the propeller?</p>
<p>Sorry for my bad english</p>
<p></p>
<p>Thank you for the help</p>
<p></p>
<p>Rui Melo</p> EDGE Performance shop visittag:zenith.aero,2023-12-29:2606393:Topic:9215902023-12-29T18:47:10.635ZJohn Myershttps://zenith.aero/profile/JohnMyers
<p>I recently visited EDGE Performance near Oslo, Norway. They take Rotax engines and parts and replace components with their own higher quality versions to create new engines. For example they use the 915 pistons, which they said are excellent, in their 912Sti, and have developed their own ECU. They also make their own intake manifold and exhaust system. Their US dealer is STOL Creek: <a href="https://stolcreek.com/">https://stolcreek.com/</a></p>
<p></p>
<p>I was very impressed with their…</p>
<p>I recently visited EDGE Performance near Oslo, Norway. They take Rotax engines and parts and replace components with their own higher quality versions to create new engines. For example they use the 915 pistons, which they said are excellent, in their 912Sti, and have developed their own ECU. They also make their own intake manifold and exhaust system. Their US dealer is STOL Creek: <a href="https://stolcreek.com/">https://stolcreek.com/</a></p>
<p></p>
<p>I was very impressed with their shop, they have a dyno setup complete with altitude and environmental testing. Their assembly area was immaculate, similar to the Rotax line itself. The owner is an engineer and their head A&P is from the US, and said he knows Sebastian. They have an old 601 in their hangar they are refurbing and putting a Rotax on. They have a brand new building at the airport in Notodden (about 1.5 hrs west of Oslo).</p>
<p></p>
<p>I am looking at their 912Sti which makes 155hp, and has a selectable eco/power mode (they have their own ECU). </p>
<p></p>
<p>If anyone is considering their engine but concerned about reliability and support, I don't know of any 3rd party manufacturer (using someone else's block) that is as high quality as theirs. I believe they also sell engines to the military for drones.</p> 915is/916is in a Cruzer?tag:zenith.aero,2023-11-06:2606393:Topic:9169592023-11-06T21:49:13.049ZJohn Myershttps://zenith.aero/profile/JohnMyers
<p>I'm looking at the Skytek FWF with a 915is or 916 in a Cruzer. Probably a 915 due to cost. I am primarily looking at this turbocharged engine to ensure I don't get stuck in a downdraft at 14,000+ DA. I would also like the cruise performance to be able to take some short cross country trips.</p>
<p></p>
<p>Mark Pensenstadler posted something recently that made me wonder how the airframe handles higher airspeeds, in terms of noise and vibration. My best guess at high speed cruise with this…</p>
<p>I'm looking at the Skytek FWF with a 915is or 916 in a Cruzer. Probably a 915 due to cost. I am primarily looking at this turbocharged engine to ensure I don't get stuck in a downdraft at 14,000+ DA. I would also like the cruise performance to be able to take some short cross country trips.</p>
<p></p>
<p>Mark Pensenstadler posted something recently that made me wonder how the airframe handles higher airspeeds, in terms of noise and vibration. My best guess at high speed cruise with this engine is 125kt TAS or about 105 kts indicated (145mph TAS / 120 mph IAS) at sub-oxygen altitudes. If it will shake/rattle at those speeds I might reconsider my engine choice.</p>
<p></p>
<p>The other complication is if the noise is just due to the prop and engine running at a high speed that wouldn't actually be an issue, as the 915 will spin the prop at about 2,000 rpm at cruise <em>(</em>115hp/9gph or 7.5gph for the more fuel efficient 916is.).</p>
<p></p>
<p>If the Cruzer won't Cruze at 125 kts I would probably look at a 914.</p> Additional alternator for 914tag:zenith.aero,2023-10-27:2606393:Topic:9160302023-10-27T22:07:55.434ZTony Renshawhttps://zenith.aero/profile/TonyRenshaw
<p><span style="font-size: 14pt;">I want to not have to be discretionary in my use of electricity and with the 914 having electric fuel pumps I reckon it might be smart to consider a 2nd alternator. I believe there is a blank up front on the crankcase for one.....I would like to hear from anyone who has first person experience with using one please? </span></p>
<p><span style="font-size: 14pt;">Thanks in anticipation.</span></p>
<p></p>
<p><span style="font-size: 14pt;">I want to not have to be discretionary in my use of electricity and with the 914 having electric fuel pumps I reckon it might be smart to consider a 2nd alternator. I believe there is a blank up front on the crankcase for one.....I would like to hear from anyone who has first person experience with using one please? </span></p>
<p><span style="font-size: 14pt;">Thanks in anticipation.</span></p>
<p></p> Rotax 914 FWF engine mount assistance requesttag:zenith.aero,2023-10-25:2606393:Topic:9158132023-10-25T11:43:26.954ZTony Renshawhttps://zenith.aero/profile/TonyRenshaw
<p>Hi,</p>
<p>I've got a 20 year old 914 that is new in a box, has never been started except maybe in the factory, that is going on my 750 Cruzer in due course. I would like to know if the firewall is the same between the 750 and the 750 Cruzer, think its a silly question but I need it verified. I also am keen to know if there is any pitfalls or things I can manage now in the choices I make with Skytek of Canada for my FWF kit. It seems like there is a fair bit involved and I only have one shot…</p>
<p>Hi,</p>
<p>I've got a 20 year old 914 that is new in a box, has never been started except maybe in the factory, that is going on my 750 Cruzer in due course. I would like to know if the firewall is the same between the 750 and the 750 Cruzer, think its a silly question but I need it verified. I also am keen to know if there is any pitfalls or things I can manage now in the choices I make with Skytek of Canada for my FWF kit. It seems like there is a fair bit involved and I only have one shot at getting it right the first time, from Canada out to Australia one way is going to cost enough, let alone if something isn't right, you'd probably resort to throwing it away. So, the ring mount is already on my engine in the box, I don't know whether that ever changed or whether it'll mate to whatever Skytek send me. If anyone has gone down the FWF path from Skytek and has a few minutes, I'd love to speak off list. My email is </p>
<p>bfreeppg@gmail.com</p>
<p>Thanks. </p> Hard starting Rotax 912 ULStag:zenith.aero,2023-03-26:2606393:Topic:8969172023-03-26T13:52:24.809ZCharles Claytonhttps://zenith.aero/profile/CharlesClayton
<p>So it started in January. I was having an unusually hard time starting my 912. The first time I killed the battery and had to jump start it. But then it ran fine for a flight. I thought it might have been because it sat for 5 weeks(tied down outside). So I figure I need to fly it more often. Next time out a week later, still hard start but I did not kill the battery. Again it ran fine. Went out about a week later, too windy to fly so I decided to just run it(apparently not a good idea).…</p>
<p>So it started in January. I was having an unusually hard time starting my 912. The first time I killed the battery and had to jump start it. But then it ran fine for a flight. I thought it might have been because it sat for 5 weeks(tied down outside). So I figure I need to fly it more often. Next time out a week later, still hard start but I did not kill the battery. Again it ran fine. Went out about a week later, too windy to fly so I decided to just run it(apparently not a good idea). Again it started hard but I was able to run it till all the temps came up. Go out a week later, beautiful day for flying and it simply refused to start. I bring the battery home to charge it and do some research. I discover that a smaller plug gap is recommended for cold weather. I pull all the plugs. They were >.030. The recommended gap was .025. I clean and re-gap the plugs. Plane fires right up. Great. Go out to fly about a week later and no start. Post on Rotax forum and suggestion is to check the floats. They weighed 6.6 grams a pair which apparently is OK. I bring all this to the attention of my A&P who admonishes me for doing all this on my own. OK so I get new plugs, and we install them, he verifies I reassembled the carbs correctly. He verifies there is spark from both ignition modules. Plane fires right up. We warm it up and check the carb sync. All good. Too late in the day to fly but I go out a couple days later and it again fires right up. A bit windy but I do a couple trips in the pattern. All good. Go out about a week and a half later and no go. Again bring battery home to charge. I decided maybe it's a battery issue so I break down and buy a Earth X 900. I can see it's much better as I'm getting much faster rotation when starting it. It basically started but before I could release the choke and add a little throttle, it died and would not start. So now I'm baffled. The carbs are on year 4 of their 5 year rebuild cycle. I'm thinking of sending the CDI modules off to Lockwood to have them tested. I saw on some other sites people having very similar issues which seemed to lead to an ignition module issue. At $1000 a piece, I'd like to really make sure that this is the problem. Any suggestions? If I rule out the CDI modules I may have to breakdown and have the flight school shop have a look. They probably have Rotax certified mechanics as they have Bristells that they use for flight training and I'd prefer not to take a shotgun approach to resolving the issue.</p> 912is return linetag:zenith.aero,2023-01-27:2606393:Topic:8906862023-01-27T21:04:12.788ZGuy Magnusonhttps://zenith.aero/profile/GuyMagnuson
<p>Has anyone had experience with installing a 912is in a CH 650. There is an excellent video by Sky Tech and Rotax for installing the 912is in a 750. The 750 uses a header tank which would be overly complicated in a low wing 650, as gravity can’t be used to keep a header tank full. The video makes a big deal about gaseous bubble being returned to the engine via the supply line. </p>
<p></p>
<p>I’ve gotten as far as using a duplex fuel switch to switch both supply and return line from wing…</p>
<p>Has anyone had experience with installing a 912is in a CH 650. There is an excellent video by Sky Tech and Rotax for installing the 912is in a 750. The 750 uses a header tank which would be overly complicated in a low wing 650, as gravity can’t be used to keep a header tank full. The video makes a big deal about gaseous bubble being returned to the engine via the supply line. </p>
<p></p>
<p>I’ve gotten as far as using a duplex fuel switch to switch both supply and return line from wing tank to wing tank but what needs to be done to insure gasses will not be returned to the engine. </p>
<p></p>
<p>Thanks</p> 912 Engine Preservation Document/Proceduretag:zenith.aero,2022-12-21:2606393:Topic:8872802022-12-21T12:23:08.441ZShai Brennerhttps://zenith.aero/profile/ShaiBrenner
<p>I will not use my airplane for about 10 months</p>
<p>Can you help me locate preservation procedure for 912 engines</p>
<p>(I only see documents for two stroke engines)</p>
<p> </p>
<p>Regards</p>
<p> </p>
<p>Shai</p>
<p>I will not use my airplane for about 10 months</p>
<p>Can you help me locate preservation procedure for 912 engines</p>
<p>(I only see documents for two stroke engines)</p>
<p> </p>
<p>Regards</p>
<p> </p>
<p>Shai</p> Senenich C70MY low inertia Propeller bladestag:zenith.aero,2022-10-24:2606393:Topic:8806672022-10-24T20:58:59.515ZMark Bengelhttps://zenith.aero/profile/MarkBengel
<p>I am looking to replace my Warp Drive propeller blades with low inertia Senenich <span>C70MY blades (low inertia foam core blades designed to fit the warp drive hub). The diameter of these blades in the warp drive hub would be 72”. Too much prop or just right for my CH-701/Rotax ULS? Anyone have experience with these blades?</span></p>
<p>I am looking to replace my Warp Drive propeller blades with low inertia Senenich <span>C70MY blades (low inertia foam core blades designed to fit the warp drive hub). The diameter of these blades in the warp drive hub would be 72”. Too much prop or just right for my CH-701/Rotax ULS? Anyone have experience with these blades?</span></p> Rotax CHT Sensor replacementtag:zenith.aero,2022-08-06:2606393:Topic:8755772022-08-06T17:35:36.166ZJack E Martinhttps://zenith.aero/profile/JackMartin
<p>I find that Rotax 912ULS CHT Sensors, part 965531, cost $195 each. Has anyone found a more economical replacement?</p>
<p>I find that Rotax 912ULS CHT Sensors, part 965531, cost $195 each. Has anyone found a more economical replacement?</p>