Guest basscheffers Posted August 19, 2010 Posted August 19, 2010 New Jab 2200 $14500 + $1500 for installation package, Rotax 912 $21000 Didnt ask about the installation package for the rotax as I fell off my chair & the phone come out of the socket. A $6K difference in price may seem a lot, but it seems a lot less of a difference if you compare completed aircraft prices. There's probably a reason no other factory builder installs them. And don't forget the 912ULS comes with twice the TBO of a Jab now. Sticker price doesn't tell you the whole story. I don't know the total cost of ownership over many years for both, it's probably about the same. But I do know I have a lot more faith in Rotax engineering!
jwatts Posted August 19, 2010 Posted August 19, 2010 I am told Jabiru have been flight testing a throttle body type injection system, not sure if that was on the 2200 or 3300 but would presume 3300 for testing purposes. Hey Watto, Wondering if you heard this from the horses mouth? Nice to have some website updates if it was true... Cheers,
Vorticity Posted August 19, 2010 Posted August 19, 2010 The aerovee..... Mmmm..... I know of three builders who have fitted aerovees to their sonex in Australia: 1. Never really produced enough power on warm days, sold the plane. 2. Could not get timing issues sorted, sold the plane. 3. Had an engine failure behind me on final. The aeroconversions guys may have a great run with them in Wisconsin but I have not heard good experience in warm climates. If you look on the sonex sites there are a heap of people upgrading to the 3300. There are some guys putting 912s in but monnett has a thing against rotax.
Mick Posted August 20, 2010 Posted August 20, 2010 I am told Jabiru have been flight testing a throttle body type injection system, not sure if that was on the 2200 or 3300 but would presume 3300 for testing purposes. I have seen it running on a 3300. The injection system looked awfully like the one Ro-Tec advertise.
Guest watto Posted August 20, 2010 Posted August 20, 2010 I cannot say from horses mouth but near enough, and yes the ***** was mentioned, no point reinventing the wheel! if there is a complimentary system out there they would be mad not to use it. I am told the fuel economy at altitude cruise is good as well.
Robert Posted August 20, 2010 Posted August 20, 2010 "I don't even understand what they need 6 cyclinders for 120HP..." Because toooo make it sound so good !!!!!!!!!
facthunter Posted August 20, 2010 Posted August 20, 2010 Why 6 cylinders.? Jabiru... Because it is smooth. Also it uses most of the parts from the 4cyl. Lycoming and continental have MANY engines which have 4 & 6 cyl variants. In a sense they are modular..Few have gone to 8 cyls in a "flat" configuration. Lycoming do but I think it is a step too far. (as with the Jab. 8.)
ianboag Posted August 20, 2010 Posted August 20, 2010 Lynn Matteson on the yahoo jabiruengines group has some sort of direct fire ignition plus a ***** TBI on the Jab 2200 in his Avid. He's a bit of a serial fiddler, but seems to (a) know what he is doing and (b) like his hardware setup.
Vev Posted August 21, 2010 Posted August 21, 2010 Jab already have a fuel injected multi port system which is sold to Israel to power UAV’s… the system is not available for manned flight and is not the be all end all answer some may think. Comparing any of the older Jab engines to the current engine is no comparison .. whilst the Carby and induction system needs improvements (which is under redevelopment) the engine has made some great strides in the last 2 years to improve cooling, lubrication and detonation management. Cheers Jack
jetjr Posted August 25, 2010 Posted August 25, 2010 Simple Digital Systems in US build main parts for Jab EFI Looks to be a good setup, No Throttle sensor or exhaust probe reqd, has in dash tuning, relatively simple to fit. Even fuel setup is fairly easy to adapt to Jabirus. Weld on bosses for each intake tube, uses automotive injectors. Uses just single high pressure pump. A throttle body with nozzle or R###C carb could be used as backup and throttle body. Probably cost $4K all up Jabiru did try a few different CARB's - not injection though. (not including UAV work?) Only fixed some problems not the whole answer. You wont see an EFI setup coming from Jabiru as they maintain everything they sell has to be able to be certified which EFI ECU's cannot be economically. There are water cooled heads coming for Jabirus, maybe even includes port for injectors Should be similar $$ as new ones from Jab.
bushpilot Posted August 25, 2010 Posted August 25, 2010 A $6K difference in price may seem a lot, but it seems a lot less of a difference if you compare completed aircraft prices. There's probably a reason no other factory builder installs them.And don't forget the 912ULS comes with twice the TBO of a Jab now. Sticker price doesn't tell you the whole story. I don't know the total cost of ownership over many years for both, it's probably about the same. But I do know I have a lot more faith in Rotax engineering! Faith is faith, but reality is just that. My experience over several years is 1 a/c with a Rotax and 3 with Jab. motors. The only in flight engine failure Ive ever had was a Rotax.. Small sample I know - but reality bites.
skeptic36 Posted August 25, 2010 Posted August 25, 2010 The only in flight engine failure Ive ever had was a Rotax.. Small sample I know - but reality bites. I think you are talking about a two stroke Rotax, probably a bit harsh on the rotax to compare it to a four stroke Jab IMHO. Regards Bill
bushpilot Posted August 25, 2010 Posted August 25, 2010 I think you are talking about a two stroke Rotax, probably a bit harsh on the rotax to compare it to a four stroke Jab IMHO.Regards Bill Correct - it was a 2-Stroke Rotax. But everything is pro-rata; a 2-stroke on an LP a/c gets used (by me at least) a lot less than 4-stroke in a HP a/c. My 2-stroke issue was at 115 hours TT. Our Jab motors have done a heap of hours. There will always be arguable factors; I'm just saying that reality based experience tends to stick in terms of an individual's perspective. But, before you say it, collective statistics over time are the ultimate test. Cheers.
eightyknots Posted August 25, 2010 Posted August 25, 2010 Weight'n'Complexity There are water cooled heads coming for Jabirus What about the extra weight and complexity this will introduce? If they are going to do that, more people are likely to purchase Rotax engines. I can see the UL engines go well, once the market accepts FADEC for light aircraft. Description
Gnarly Gnu Posted August 26, 2010 Posted August 26, 2010 There are water cooled heads coming for Jabirus, maybe even includes port for injectors This sounds promising, just what the Jab engines require to improve their power and reliability. The company that supplies water cooled conversion for Lyc's report a significant power increase not to mention top end reliability improvement which would be the real bonus.
facthunter Posted August 26, 2010 Posted August 26, 2010 Liquid cooled ? The main advantage of liquid cooling is that running clearances of the piston can be reduced. This cuts down blowby as the pistons don't rock so much. We are getting more complex aren't we? Just fitting liquid cooled heads is a piecemeal result. Aircooled heads & barrells should be separate, but liquid cooled ones can be in a unitary bank or incorporated in a single cast block. ( In-line or Vee). Done properly it will be lighter and certainly stiffer than either the Jab or rotax. Have to be a casting though. (Could look strangely like a Subaru.) It would be Bye Bye to Jabs CNC'd engines . There is plenty of air around aeroplanes. It's a fairly logical application for an aircooled engine. Nev
t4flyer Posted August 26, 2010 Posted August 26, 2010 I would have thought the main problem with the Jab motor was the carb and its positioning. Firstly a single carb will never provide optimum fuel distribution and therefore the engine cannot be tuned for maximum performance and the carb positioning on the Jabi is not good at all. Secondly Jabiru carbs have a known icing tendency. Replacing the carb with a TBI might solve the Jabi's icing tendency (I use an Aerocarb TBI on my VW powered Zodiac, no carb heat and no icing) but it wont solve the less than perfect fuel distribution problem. Water cooling and staying with a single carb or a single TBI is "in my opinion" not the answer. The current engines are proven designs with a flaw "the carb and manifold system" a good multi-point EFI system would solve both problems and possibly allow a little more power to be squeezed out of the engine due to a more optimum state of tuning. Cheers, T4Flyer.
jetjr Posted August 27, 2010 Posted August 27, 2010 I agree with the liquid cooled heads being an add on but without full re design what do you do? A key issue Im told is the material Jabiru heads are made from, great for CNC production but not so good for heads. These new LC ones are cast from much more suitable materials, whole kit should not raise weight that much, weight of coolant is hoped to be it. Also being worked on is dry sump arrangement - you thought liquid cooling pushed it towards Rotax design!! Port EFI is out there - just needs final parts to adapt it to Jabiru.
facthunter Posted August 27, 2010 Posted August 27, 2010 Castings. Right about the materials. The problem with heads using castings is quality control. You often get porosity. I don't feel this is terrninal with air cooled heads, but more critical with liquid cooling, as you will vent the coolant overboard, or get steam pockets. I really don't believe the Bing CD carb is any more prone to icing than any other. Both the Rotax and Jab use it and the rotax has 2 of the damn things without much imorovement in fuel distribution. ( The pulsing is uneven) Can't see the point of dry sumping at all. Even quite a few inverted oil system engines don't use it. You don't need oil and water and fuel pipes all around the cowl any more than you have to. Radial and inverted engines need dry sump, but otherwise forget it. The FADEC engine by Continental ( 0-200D) is a proven basic engine but there may be some bugs with the engine management. (Anybody heard anything?) Nev.
Guest ozzie Posted August 27, 2010 Posted August 27, 2010 one thing i noticed with dual carbs is the lack of a balance tube between the two carbs on the manifold side. As it reads a balance tube keeps the induction system more balanced in manifold pressure and allows for slight differences between the two carbs smoother running and idle. icing problems are more to do with the air induction setup reather than the carb itself. avoid sharp bends and narrowing of the air inlet hoses will help here.
bushpilot Posted August 27, 2010 Posted August 27, 2010 I really don't believe the Bing CD carb is any more prone to icing than any other. Both the Rotax and Jab use it and the rotax has 2 of the damn things without much imorovement in fuel distribution....... Nev. Our 3300 Jabs are much more prone to icing than our 2200s. Not sure why, but other owners report that as well.
Steve L Posted August 27, 2010 Posted August 27, 2010 the 3300 engine draws a lot more air throught the carby than the 2200, its like turning a compressed air valve on the more air you let throught it the more it ices up
S.Drifter Posted September 1, 2010 Posted September 1, 2010 Jabiru's idea was for everything to be simple. The Rotax has , 2 TWO ?? Carbs and NO fuel injection. All the trouble getting the carbs balanced. and spring loaded to open. Have to hold the throttle closed half the time. Hate it.There goes the cheap plane concept. The rotax is certainly expensive to buy and for parts. Fortunately it doesn't need them very often. We need other engine options. Nev It's not necessary have the throttle springloaded to open, it's a very simple fix to have springload to close . Its already there from factory. Check balance every 100hrs, need to adjust every second blue moon .
Kod Posted September 2, 2010 Posted September 2, 2010 The 8 cyl isn't being produced anymore. They had to much trouble with fuel distribution, and thermal heating. Something like that. They only made by order now
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