On 1/23/2010 8:39 AM, teledynmcs@aol.com wrote:
> >>>>>Jabiru is not a good solution! I know many engines for sales in
> France replaced
> by Rotax. <<Reliability>><<<<<
> Greetings Team,
> Once again, someone repeats negative rumors about the Jabiru 3300
> without actual, hands on Jabiru experience. This happens
> virtually every time someone mentions a Jabiru engine on this forum
> and it's gone beyond being very tiresome and has crossed into vague,
> rumored bullshit.
> What specifically were the problems you cite that caused the Jabiru
> engines you speak of to be unreliable and replaced with Rotaxs?
> Please elaborate. A little more info, rather than a broad, sweeping
> indictment and condemnation of Jabiru would be far more helpful. I
> personally know first hand of three Rotax 914's that have sustained
> broken cranks due to turbo over boost situations when the turbo waste
> gate stuck shut. I've also seen Rotax 912's with cracked cylinders,
> cracked and/or fretted cases, cracked exhaust, and spun main bearings
> due to improper oil purging during oil changes and I've heard second
> hand about a lot more issues. Anyone with a decent set of eyes can see
> that the Rotax is far, far more complicated than the Jabiru. For years
> now, right here on this very forum, I've read again and again of the
> trials and tribulations of Europaphiles and their various troubles
> with Rotax engines. Would it be fair for me to say that all Rotax
> engines are crap based on these events and forum posts? Of course not!
> It all boils down to how each engine is operated.
> Some of the early Jabiru engines had reliability issues, mostly due to
> inadequate cooling because the cooling fins on the cylinder heads were
> too small. That is well known and the problems associated with that
> issue have been corrected. There was also a problem with the bolts
> fretting and breaking that attach the flywheel, but that has been
> narrowed down to engines that had sustained unreported prop strikes.
> This issue has likewise been corrected by installing pins between the
> flywheel and the crank in newer engines and replacing the
> flywheel bolts with stronger bolts and tighter torque on older
> engines. Similarly, although it's been a bit longer since the Rotax
> debuted and many who are new or relatively new to sport aviation may
> not remember or be aware, but many of the early Rotax 912/914 engines
> also had serious reliability issues. Read through the Rotax published
> SB's and AD's and familiarize yourself with the issues that have
> plagued the Rotax 912/914 series engines over the years before you
> bash Jabiru outright. Some of that stuff will curl your hair and make
> you think the Rotax 912/914 isn't suitable for use on a lawn
> mower. Why do you think there are dozens of Rotax Service Directives
> to comply with? Hint: it's not because the Rotax's were reliable in
> the early days of production!
> In fact, the 912/914 still has reliability issues if not properly
> taken care of and Jabiru, Lycoming, Continental, Franklin, Subaru,
> Limbach, et al, are no different. Dozens, if not hundreds, of posts
> have been put up right here on this forum covering a wide range of
> reliability issues with the Rotax 912/914. These include, but are not
> limited to, engine cooling, carb issues, turbo issues, leaks, slipper
> clutch and redrive issues and ignition issues. You simply cannot run
> either of these engines with the wrong oil or improper cooling or the
> wrong prop loading or improper maintenance and expect a high degree of
> reliability. It just won't happen.
> Just because the manufacturer's name is Rotax does not instantly mean
> bullet proof. Quite the contrary. Likewise, just because the
> manufacturer's name is Jabiru doesn't mean it's unreliable, but that
> theme seems to get repeated here adnauseum. This notion that
> overall the Jabiru 3300 engine is unreliable is a pure and
> unadulterated myth that continues to be repeated again and again here
> on this forum with little or nothing of substance to back up the
> claim. I personally know several dozen Jabiru owners who could not be
> happier with their engines, myself included. A while back the Jabiru
> 3300 with hydraulic lifters passed JAR certification. Unreliable?
> Funny, the JAR didn't seem to think so!
> I have admitted I had some initial problems getting my CHT's to run
> cool, but that was my fault for not understanding how to make the
> head cooling work. I was blazing a new trail insofar as the cowl set
> and head ducts I was using and, at the time, there were only a handful
> of Europas flying with Jabiru engines installed. So, it stands to
> reason that, with little guidance, I would have
> some problems until I educated myself and got it all sorted out.
> That's why they call these things "experimental", right? I also had
> high EGT's initially, but again, that was my fault for not
> fully understanding the relationship between airframe drag, carb
> tuning, prop pitch and EGT's.
> The Jabiru engine comes from the factory tuned specifically for the
> Jabiru airframe. If you hang a stock Jabiru engine on a much cleaner
> airframe, like a Europa, it presents less load to the engine
> throughout the RPM range and the result is the engine runs leaner. If
> this situation isn't corrected, you will have reliability issues,
> i.e., hotter EGT's and CHT's, burnt exhaust valves, etc. If you hang a
> stock Jabiru engine on a drag queen, like a CH701 or something
> similar, the load presented to the engine is greater and results in a
> richer running engine and reliability issues will result if not
> corrected, i.e., flooding, fouled plugs, etc.
> Each operator/builder must carefully choose (or tune) the prop and
> tune the carb for your specific airframe in order to keep the engine
> happy and within approved operating parameters. You must also make
> sure that the heads get adequate cooling flow. Like purging the oil
> system on a Rotax with every oil change, this tuning is just something
> you have to do in order to make a Jabiru work properly in your
> airplane. In this incidence reliability has far more to do with the
> carburetor tuning and prop pitch as it relates to airframe drag than
> it does the engine itself. If you don't adjust the tuning to suit your
> airframe, yes, you are going to have problems, but is that Jabiru's
> fault? Hardly. Jabiru tells you exactly how to do it and if the owner
> doesn't comply it isn't Jabiru's fault. Period.
> Graham, in regard to the intake plenum and turbulated flow entering
> the carb, I think you have it exactly backwards, at least insofar as
> the Jabiru/Bing set up is concerned and what I have learned from my
> own experience with this engine. I have a smooth bore radiator hose
> with a 90 degree bend that ducts air from my air filter box mounted on
> the firewall down and into the Bing carby on the back of the Jabiru.
> Initially, I had gross unevenness in my EGT's across the RPM range. I
> installed a vane (+) inside the intake plenum just up stream from the
> carby made from .025" stainless sheet to smooth out the airflow before
> it entered the carb. My EGT's went from a 200F hottest to coolest, to
> a spread down to about 50F just by installing this vane with no other
> change made. The airflow entering the Jabiru intake splitter
> downstream of the carb must be smooth in order to have even
> distribution of the fuel/air mixture to all cylinders. Turbulated air
> flow results in uneven EGT's.
> It is also crucial that the prop be properly tuned (if adjustable) or
> chosen specifically for climb and cruise parameters (EGT vs RPM) for
> the airframe in order to achieve acceptable EGT's. By lowering the
> EGT's you also will affect the CHT's. Jabiru has published Service
> Bulletins on how to do this. Jabiru USA in Shelbyville offers a great
> 3 day course on the Jabiru engine that covers this topic in great
> depth. These guys really have this figured out. I highly recommend
> anyone considering this engine take this course. The knowledge you
> will gain is worth every penny of the $300 entry fee. Because Jabiru
> uses the Bing carb the 2200 and 3300 both are sensitive to prop and
> airframe loading, as well as carburetor tuning (jetting). Personally,
> I would love to see someone develop direct fuel injection for this
> engine. I tried a Rotec TBI, but I couldn't make it fit because of a
> conflict with the engine mounts. Some Jabiru owners, primarily Sonex
> builders, are using the Aerocarb, but there have been numerous
> problems reported with it. The Bing is basically a motorcycle carb and
> doesn't lend itself very well to this application unless properly
> tuned and even then it has shortcomings.
> The 3300 is a powerful little engine. It's simple and robustly built,
> far simpler and more robust that the Rotax. I've seen first hand how
> both engines are built internally. For incidence, the Jabiru has main
> bearings between each con rod on the crank, not just on the ends and
> in the middle like a Rotax 912/914. The crank in the Jabiru is much
> better supported than the crank in the 912/914. A quick peek inside
> each engine and seeing how they are built won't leave you with a lot
> of confidence in the robustness of the Rotax, that is for sure. The
> parts for the Jabiru overall are cheaper, and many commonly
> replaceable parts are available at auto parts stores over the counter.
> If properly tuned and maintained, there is absolutely no reason why
> the Jabiru shouldn't be a very reliable engine in any airframe and a
> lot cheaper to operate than the Rotax, but you have to adjust the
> tuning to match your airframe combination in order to make it work.
> I'm very pleased with my Jabiru, especially now that I have been
> through the Jabiru engine course and I fully understand how the engine
> is built, how the Bing carby operates and how to tune it and the
> prop for airframe drag (or lack thereof). My Europa is a trigear. I'm
> running a Sensenich carbon ground adjustable prop. I do not have
> straight pipes, but I do have the newer 3 into 1 exhaust
> manifold arrangement with an expansion chamber (muffler) and a single
> exhaust stack. I see climb rates solo a bit over 1800 fpm and 1400 fpm
> with two on board with full fuel and full baggage. I cruise at 128-130
> kts at 5 gph. Top speed at WOT is a bit over 160 kts indicated, all
> for $12,000 less than the Rotax.
> FWIW, just so everyone will know that I have nothing against Rotax. As
> I have mentioned here before I also own an Aeromot Ximango AMT200S
> motorglider. My Ximango has a certified 912S installed. I compare the
> Jabiru 3300 to the Rotax 912S on an almost daily basis (except now
> because it's January and the weather is crap). I've been comparing
> these engines directly from both an operational and
> maintenance standpoint for nearly three years now. I cannot see any
> distinct advantage of the Rotax over the Jabiru or vice versa in these
> direct comparisons. Several things I have noticed are worth
> mentioning, though.
> The Rotax engines are very expensive for those of us on this side of
> the pond with the current exchange rate. Likewise, Rotax parts, when
> compared to Jabiru parts, are definitely more expensive, much more
> expensive. Oil changes with the Rotax are a pain in the ass compared
> to changing the oil in the Jabiru. The Rotax is a far, far more
> complicated engine when compared to the Jabiru. If you believe in the
> K.I.S.S. principle for aviation related components, this bodes well
> for the Jabiru. The Rotax is probably a better choice for my
> motorglider because the wet heads help slow the engine cooling,
> avoiding shock cooling, when I shut the engine down to soar after
> climbing to usable lift. There is no second carburetor on the Jabiru
> to keep in sync as with the Rotax. With the Jabiru, set it and forget
> it. The Jabiru has fixed timing with simple, dual distributors, as
> opposed to an $800 ignition module that will leave you stranded if and
> when it fails. My 3300 is a solid lifter version and I do have to
> torque the heads and keep the valve tappet clearance adjusted
> regularly. I time that maintenance with my oil changes and can
> easily torque the heads and adjust the valves while the oil is
> draining with time to spare. Otherwise, I'm really enjoying the extra
> 30 or so HP that the Jabiru offers my Europa over the 912S. I also
> like the throaty, real airplane engine sound of the Jabiru over the
> whiny noise the Rotax makes. The Jabiru is also a far, far smoother
> running engine with MUCH less vibration than the Rotax. I say this not
> only from a pilot feel standpoint, but also because I've had both
> props balanced using an ACER Probalancer. Interestingly, my Jabiru
> needed no further adjustments to achieve perfect balance. The Rotax
> required some counter weights to balance the prop.
> So, with all this said, enough already with this second hand Jabiru
> bashing. If you have specific, first hand experience
> with issues regarding the Jabiru 3300, let's hear 'em and we'll talk
> about it. Broad based condemnation of either engine is useless to
> everyone and only fuels the rumor mill. IMHO, the Jabiru 3300 is a
> fine little engine and if I had it to do all over again I would
> indeed buy another Jabiru for my Europa. My experience and the
> experiences related to me by the fine folks at Jabiru USA and
> Lightning Aircraft in Shelbyville, TN, show that, more often than
> not, it is the operators that have the problem because they aren't
> tuning the prop and carb to suit their airframes or they are running
> the wrong oil or they are allowing the engine to run hot, or otherwise
> abusing or not properly maintaining the engine. I can cite literally
> dozens of failures in Rotax's that have resulted from the same sort of
> abuse if you'd like, but you can learn about them yourself by reading
> through the Rotax SB's and AD's.
> BTW, anyone who is interested please note that my email is changing at
> the end of the month. My new email will be wingdingy@gmail.com
> <mailto:wingdingy@gmail.com>. This address is up and running now.
> Sorry for the inconvenience.
> Regards,
> John Lawton
> Whitwell, TN (TN89)
> N245E - Flying and lovin' every minute of it!
> *
> Amen John.
> *
Dale
Europa Tri-Gear
Jab 3300
> *
>
> *
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