Guest Maj Millard Posted November 3, 2009 Posted November 3, 2009 One of thier biggest mistakes IMOP......................................................
Guest Qwerty Posted November 3, 2009 Posted November 3, 2009 A mate is building a J170 destined to be 912s powered. I am looking forward to a ride. I also think it will be a good aircraft. On the quality control issue, I am informed that a J3300 suffered complete and catastrophic failure in flight. The J230 was landed OK. The cause was reported to me as "no thread locking compound on a big end bolt and this was a factory assembled engine" Jabiru does not accept any responsability for the occurence. This is what I have been told by (name withheld) who is closely associated with the incident. *Qwerty prepares for a law suit* Cheers.
Guest Maj Millard Posted November 3, 2009 Posted November 3, 2009 Give us more Querty, This could be a significant event, the 3300s are supposed to be 'all right' at least by their owners. Catostrophic engine failure in flight is a dangerous thing.....................................................................
Guest Qwerty Posted November 3, 2009 Posted November 3, 2009 Not much more to tell really. As it was related to me, allegedly, the bigend let go, the engine self destructed in-flight. The cause was traced to a clean factory installed bigend bolt that should have had thread locking compound on it. There is a lot of peripheral detail about the engine that will/is no doubt being use to muddy the issue. Its history and other problems all of which were top end/cam/hyd lifter problems and unrelated to the bigend were also factory caused but the clean factory installed bigend bolt is what matters. This was a low hour engine too, I can't remember exactly but I think it was low 200s. Allegedly Allegedly Allegedly *now waiting for two law suits* :peepwall:
dazza 38 Posted November 3, 2009 Posted November 3, 2009 Whats the answer ? (i dont mean install a 912), as i have said previously the maturity of their basic engine design is around 15 or so years old. IMO it should have the bugs ironed out by now.As mentioned by another gentlemen, maybe their should be a thread specifically were owners can install photos, and a description of damaged caused, but feed back must be allowed, because other wise it is pointless. As i have previously read from other colleagues , if true, commercial grade parts IMO have no place in aviation, period. I have heard that they use 'car parts in their engines', in theory it shouldnt be a problem,(because cars are reliable right, generally they are,well most brands are anyway). I am not a jabiru hater, quite opposite i like them, and i liked flying them. But the reliabilty was enought for me to move on to another A/C. I just hope that somebody or a engine company or any third party might be able to find a solution to these reliablity problems, real or otherwise because i think their are alot of concerned owners out the scared $hitless, that something is going to go wrong to their engines, or airframe. Kind regards Daryl
Yenn Posted November 4, 2009 Posted November 4, 2009 4aplat. Any chance of a translation or even a summary?
Guest 4aplat Posted November 4, 2009 Posted November 4, 2009 4aplat. Any chance of a translation or even a summary? I will try .........
jetboy Posted November 4, 2009 Posted November 4, 2009 Hi Daryl, yeah it would be nice to have an answer too but in this real world it comes down to when and how often you are prepared to pay for these features, like you can go for an unproven copy of the Jabiru with EFI and all the works for a lot more $ (or check out their new carb. version - why have they gone back?). The truth is all the engines have car parts (tractor, actually, for the Continental/Lycomings - where did you think Slick mags came from?) or better still snowmobile motorcycle and lawntractor stuff used. I'm happy with pistons from Repco (but not Holden, please) in my 2200 as long as the alloys used are up to it I dont consider it a bad thing that the same alloys might be used in engines for other roles. VW, Subies if modified well seem to cut it OK in aircraft; yes I am concerned about my engine but less so than some others I used to fly even the O-200 can have a few bad days it just has more warning and more $ to fix Cheers, Ralph Whats the answer ? (i dont mean install a 912), as i have said previously the maturity of their basic engine design is around 15 or so years old. IMO it should have the bugs ironed out by now.As mentioned by another gentlemen, maybe their should be a thread specifically were owners can install photos, and a description of damaged caused, but feed back must be allowed, because other wise it is pointless. As i have previously read from other colleagues , if true, commercial grade parts IMO have no place in aviation, period. I have heard that they use 'car parts in their engines', in theory it shouldnt be a problem,(because cars are reliable right, generally they are,well most brands are anyway). I am not a jabiru hater, quite opposite i like them, and i liked flying them. But the reliabilty was enought for me to move on to another A/C. I just hope that somebody or a engine company or any third party might be able to find a solution to these reliablity problems, real or otherwise because i think their are alot of concerned owners out the scared $hitless, that something is going to go wrong to their engines, or airframe. Kind regards Daryl
dazza 38 Posted November 4, 2009 Posted November 4, 2009 Hi jetboy, i am hearing ya, Continental, lycoming, etc have all had defects for one thing or another.(lycoming had that defect on their crank is a specific model just recently). I really hope the little things are sorted out sooner rather than later. Cheers and happy flying.
David Packham Posted November 17, 2009 Posted November 17, 2009 Just taken ownership of X-air with Jab 2200 Number 1261. 240 hours no apparent problems.
Guest 4aplat Posted November 17, 2009 Posted November 17, 2009 no problem for me with the jab on the x-air............. untill 400 hours ..... godd luck MicheL
Yenn Posted November 24, 2009 Posted November 24, 2009 There is athread where owners can post problems with Jab engines. It was started by Rickp a long time ago and as far as I can see very little has been posted, but we still keep hearing these second hand stories of failures of the engines.
jetboy Posted November 24, 2009 Posted November 24, 2009 The weekend yielded another mechanical problem, not my engine but a similar 2200a solid lifter with the last of the thick fin heads, done about 150 hrs since crank replacement and 25 hrs since valvegrind due to low compressions. Rough running on startup all valve clearances checked OK except last exhaust one where the rocker was observed not moving - pushrod jammed on side of tube. The adjuster nut appeared set correctly and still locked. Owner is currently researching conversion to Rotary. I dont blame him. But the point is, how did this happen and is it common? Ralph
Captain Posted November 24, 2009 Posted November 24, 2009 The weekend yielded another mechanical problem, not my engine but a similar 2200a solid lifter with the last of the thick fin heads, done about 150 hrs since crank replacement and 25 hrs since valvegrind due to low compressions.Rough running on startup all valve clearances checked OK except last exhaust one where the rocker was observed not moving - pushrod jammed on side of tube. The adjuster nut appeared set correctly and still locked. Owner is currently researching conversion to Rotary. I dont blame him. But the point is, how did this happen and is it common? Ralph I assume all valves were ground 25 hrs ago by somebody up your way ......... and now there is a problem with the reassemby and your + the owner's 1st thoughts are that it is a fundamental Jabiru fault, needing an engine replacement?????? Wow. I'm sympathetic if the valve grind & reassembly was done at the factory .... but surely the 1st place to look would be with whoever did the job, if it was not?
jetboy Posted November 24, 2009 Posted November 24, 2009 Without speculation would like to know if this has happened to others. (see original post of this thread) I dont see any design or maintenance issue that could have led to the pushrod getting out of the cup and up beside the rocker when the engine had been running for 25hrs OK and no evidence that the adjuster had undone. Someone here might know a scenario. I know with my own engine the pushrods dont allways seat first try into the camfollowers but they snapped into place as soon as the crank was turned so I'd expect that not to be a cause of pushrod disconnect after 25 hrs running. I'm thinking if the valve had stuck open would that allow the pushrod to dislodge? If it dropped a seat I'd expect it to be still 'dropped' and not apparently functioning normal now. The pushrod appeared undamaged (resting against soft ali tube) The prior work was done by a LAME shop and earlier major work done by the agents and at Bundaberg. Ralph
RKW Posted February 9, 2010 Posted February 9, 2010 The engine on my J160 popped its cork last thursday. Two of the through-bolts which hold the cylinders and the crankcase halves together broke with almost total loss of power. Took said motor to the factory in Bundy and it is now being repaired. I have good reason to believe this is a fairly common problem. From a laymans perspective, the bolts appear to be a fair bit too small in diameter and I suggested this to the people at Jab. I was assured that the tensile strength of the bolts were more than adequate and will NEVER be upgraded. There are many reasons why they break so they tell me, none of which has anything to do with the diameter. The bolts are machined out of 10mm chrome molly stock and they taper to 3/8th on the ends. I cannot see how it is possible to guarantee the tensile strength of a bolt with a machined or cut thread. Most high tensile bolts have a rolled thread. The motor was at the latest spec including the new hydraulic lifter cam and had a little over 300 hours on it when it let go. I am not confident that the problem is being properly addressed. Best regards, Bob
jetjr Posted February 9, 2010 Posted February 9, 2010 "There are many reasons why they break so they tell me, none of which has anything to do with the diameter." What are the reasons they gave? Regarding bolt strength, in some applications if a bolt is stregthened, the root cause of the problem is transfered and causes another breakage even more serious You also said "almost total loss of power" what actually happened?
RKW Posted February 9, 2010 Posted February 9, 2010 Hi Jetjr, Thankfully, I was't flying it at the time, but the person who was, experienced vibrations and loss of power. Insufficient power to maintain altitude. Fortunately, high enough and close enough to return to the airfield safely. As for the reasons for the bolts breaking, they did not give me any as yet. I was told that there are ten things that can cause this to happen. I'm hoping that they will enlighten me when the motor is stripped. Regarding the possibility of transferring the problem and causing a breakage somewhere else, I take your point, but it's serious enough when three of the four cylinders are coming adrift and oil is pouring out. Thank you for your interest. Regards, Bob
Brett Posted February 9, 2010 Posted February 9, 2010 Not jabiru related but similar,, the old VW motors (type 3 case) used to use 10 mm bolts and as the motor heated up unevenly they used to pull the threads out of the case, as the bolts had no give in them ,, installing case savers (they call them) basically just an 8mm helicoil and using 8mm studs ,they tended to stretch more and alas didn't have a problem again.. this is the comon practice now basically on any vw conversion I've seen. I wonder if a similar thing may fix this issue with the jab motor.
old man emu Posted February 9, 2010 Posted February 9, 2010 The engine on my J160 popped its cork last thursday. Two of the through-bolts which hold the cylinders and the crankcase halves together broke with almost total loss of power. Best regards, Bob We have just had a similar situation with a flying school aircraft we maintain. We replaced the through bolts and put the aircraft back into service. The operators then complained that the engine was stiffer than others when pulled through. Further examination leads us to believe that the crankshaft may have be out of alignment with the bearings. We hope to find out after the enfine has been pulled down at Jabiru. Old Man Emu
RKW Posted February 9, 2010 Posted February 9, 2010 Hello Old Man Emu, When the bolts let go, there is a fair amount of hammering of the main bearings as the two halves of the crankcase are trying to separate. Its possible that the bearings and the crankcase have copped a hiding. Hopefully the good people at Bundy will let us know what causes this. Regards, Bob
nong Posted February 9, 2010 Posted February 9, 2010 AFAIK Porsche involvement with Harley was actually on the Revolution engine which came out earlier this decade (& is liquid cooled). Such credit as the Evo engine deserves is Harleys entirely - it may have helped save the company but punative import tarrifs on overseas bikes didn't hurt them either ! Cheers John Of course Walter is right. Porsche were in the thick of EVO development. Bale out CreZ...you're going down in flames !!
Guest Walter Buschor Posted February 9, 2010 Posted February 9, 2010 Hi Nong, good to have my coments confirmed. !! For fear of repeating myself and also getting sidetraked a little Porsche had decades of trouble with their aircooled engines in regards to crankcase / cylinder bolt brekages . This was due to unequal thermal expansion of the alloys and steels used . These problems and attempted fixes did not bring the desired result until close to the end of the Aircooled engine. ( I know as I still have an older 911 and paid for all it's failings ). Porsche did however fix it in the end. I don't suggest that Jabiru should contract Porsche to fix their problems but Jabiru could see what Porsche did to adress the problem as it is well documented.:gerg: Both these engines have a lot in common and the root cause might be the same. fly safe Walter
Tomo Posted February 9, 2010 Posted February 9, 2010 G'day RKW, sorry to hear about your problem. I'm interested in what cylinder it was, and which of the four bolts broke? if it was all of them, or just one or two? Do you run avgas or mogas? Thanks
Guest Crezzi Posted February 9, 2010 Posted February 9, 2010 Of course Walter is right. Porsche were in the thick of EVO development. Bale out CreZ...you're going down in flames !! It wouldn't be the first time but I can't find any evidence that Porsche had anything to do with the evo design (unlike the revolution). Harley-Davidson Evolution engine - Wikipedia, the free encyclopedia Harley-Davidson - Wikipedia, the free encyclopedia Could you perhaps be thinking of the Nova which apparently was a V4 project Porsche did for Harley whilst they were busy with the Evo ? Cheers John
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