Aeromomentum on any 601 model? - Zenith Aircraft Builders and Flyers2024-03-28T22:21:27Zhttps://zenith.aero/forum/topics/aeromomentum-on-any-601-model?commentId=2606393%3AComment%3A730218&feed=yes&xn_auth=noIn a high drag low airspeed a…tag:zenith.aero,2020-07-30:2606393:Comment:7305302020-07-30T17:26:48.433ZJohn Austinhttps://zenith.aero/profile/JohnLAustin
<p><em>In a high drag low airspeed airframe to Jabiru is not happy</em></p>
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<p>I've got 8 years and nearly 650 trouble-free hours with a Jab 3300 (late Generation 2/early Generation 3 or so-called "late hydraulic lifter" engine) in my STOL 750. I, too, was concerned about putting an air-cooled 6-cylinder engine in a high drag, low speed airframe, but if one is willing to do meticulous tweaking of the cooling air flow, the engine can be quite "happy!"</p>
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<p>I routinely run…</p>
<p><em>In a high drag low airspeed airframe to Jabiru is not happy</em></p>
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<p>I've got 8 years and nearly 650 trouble-free hours with a Jab 3300 (late Generation 2/early Generation 3 or so-called "late hydraulic lifter" engine) in my STOL 750. I, too, was concerned about putting an air-cooled 6-cylinder engine in a high drag, low speed airframe, but if one is willing to do meticulous tweaking of the cooling air flow, the engine can be quite "happy!"</p>
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<p>I routinely run CHT's (measured with air-flow-shielded sensors at the hole between the plugs, which is likely higher and closer to reality than the typical under-the-plug ring terminal) in the 250's F range in the winter and the 275's F range in the summer, all the while cruising (no slats) at 82-84 kts (95+ mph). My engine/prop DynaVibe balanced to .03 ips, which is less than half the limits of human perception! It's hard to be a 6-cylinder for smoothness and that 6's sweet sound is only exceeded by a Merlin!</p>
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<p>Jabiru has been building engines for over 3 decades. There were some problems with early engines and thanks to the internet where negative reports never go away, it continues to haunt Jab's reputation. However, like all modern manufacturers, they have undergone continuous quality improvement and now are on their 4th Generation engine and the reports of owner experience have been uniformly good.</p>
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<p>I have no experience with the 601/650, but seems to me the modern Jab would be even easier to cool in that airframe vs the 750. Just pointing out that the modern Jabiru engine has evolved and there are a great number of successful installations in Zenith aircraft. </p>
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<p>However, I agree with Bob that the Rotax is definitely more "plug and play," although my hangar-mate has one on his RANS and it seems to be much more maintenance-intensive (and expensive!). The AeroMomentum is also very appealing, particularly for those who enjoy experimentation and trying new things. We should be seeing more and more reports as this new engine works its way into the market - hopefully successful reports!</p>
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<p>As one member always says, "It's nice to have choices."</p>
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<p>John</p>
<p>N750A</p>
<p></p> A 912UL would be a solid choi…tag:zenith.aero,2020-07-28:2606393:Comment:7303162020-07-28T19:18:55.696ZIan Robbhttps://zenith.aero/profile/IanRobb
<p>A 912UL would be a solid choice, but without much performance improvement, if any. A 912ULS would have a bit more performance. But, for not much more you can have an AM15, which at the very least is a 38% power gain over the Jabiru. Step to the highest output AM15, and it's 73% more power(147HP). Aeromomentum is not proven yet, but just give it time.</p>
<p>A 912UL would be a solid choice, but without much performance improvement, if any. A 912ULS would have a bit more performance. But, for not much more you can have an AM15, which at the very least is a 38% power gain over the Jabiru. Step to the highest output AM15, and it's 73% more power(147HP). Aeromomentum is not proven yet, but just give it time.</p> No offence taken. I have Test…tag:zenith.aero,2020-07-28:2606393:Comment:7303582020-07-28T19:13:49.739ZBob McDonaldhttps://zenith.aero/profile/BobMcDonald
<p>No offence taken. I have Test flown Zenith aircraft with both the Jabiru 2200 & 3300 engines, and test flown the CH701 with the UL Power engine. I have had lots of engine "issues" on the Jabiru 3300 in CH601XL-B & CH750 aircraft. In a high drag low airspeed airframe to Jabiru is not happy. They looked so promising but performance disappointed me. The Rotax 912A series (originally a 600 hr TBO engine out of a Katana) in my 2005 CH601HD has had no issues in 1200+ hours of flying. I…</p>
<p>No offence taken. I have Test flown Zenith aircraft with both the Jabiru 2200 & 3300 engines, and test flown the CH701 with the UL Power engine. I have had lots of engine "issues" on the Jabiru 3300 in CH601XL-B & CH750 aircraft. In a high drag low airspeed airframe to Jabiru is not happy. They looked so promising but performance disappointed me. The Rotax 912A series (originally a 600 hr TBO engine out of a Katana) in my 2005 CH601HD has had no issues in 1200+ hours of flying. I flew 325 trouble free hours on my Rotax 912S in the 2010 CH750 I built then sold it. The new owner jumped in and flew it across (5 days) Canada to Northern Alberta where is continues to fly. AM15 engines I have no real world experience with. I think we can agree on the Jabiru engine. Fly safe.</p> Bob,
While I certainly respec…tag:zenith.aero,2020-07-28:2606393:Comment:7302182020-07-28T15:14:00.930ZMike Brennerhttps://zenith.aero/profile/MikeBrenner
<p>Bob,</p>
<p>While I certainly respect your opinion, it doesn't really answer any of the questions I asked. The Jabiru I'm replacing is also a "proven engine and proven install package available from Zenith" but in <span style="text-decoration: underline;">my</span> <span style="text-decoration: underline;">opinion</span>, it's a piece of junk that's given me nothing but trouble since the day I installed it in 2007.</p>
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<p>Bob,</p>
<p>While I certainly respect your opinion, it doesn't really answer any of the questions I asked. The Jabiru I'm replacing is also a "proven engine and proven install package available from Zenith" but in <span style="text-decoration: underline;">my</span> <span style="text-decoration: underline;">opinion</span>, it's a piece of junk that's given me nothing but trouble since the day I installed it in 2007.</p>
<p></p> Put a Rotax 912 or 912S serie…tag:zenith.aero,2020-07-28:2606393:Comment:7302112020-07-28T14:12:24.840ZBob McDonaldhttps://zenith.aero/profile/BobMcDonald
<p>Put a Rotax 912 or 912S series engine on the HDS. Proven engine and proven engine install package available from Zenith. </p>
<p>Complete engine mounts, aux. parts, cowls everything ready to bolt on from Zenith. Even buying a "gently used" Rotax 912 series to reduce costs is a safer path to travel. A solid reliable engine is the best life insurance you can buy.</p>
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<p>My 2 cents. </p>
<p>Put a Rotax 912 or 912S series engine on the HDS. Proven engine and proven engine install package available from Zenith. </p>
<p>Complete engine mounts, aux. parts, cowls everything ready to bolt on from Zenith. Even buying a "gently used" Rotax 912 series to reduce costs is a safer path to travel. A solid reliable engine is the best life insurance you can buy.</p>
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<p>My 2 cents. </p>