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dlegg

New through bolt AD

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Well, a damn good point of reference! Rotax provides NO warranty as to the selection, use etc. of the 912. It is at the owner's risk as to the use it is put. So when the crankshaft comes into issue for multiple thousands of them, you're on your own.

It's normal industry practice for a component supplier who markets a product which can be used in many applications to do this.

 

For example, I'd be surprised if Briggs and Stratton don't have the same policy for their stationary engines, and I bought a Honda stationary engine which specifically threw the onus on application induced issues on me.

 

However they are all still bound by the legal Statutory Warranty they have to offer regarding manufacturing defects, which is a different thing.

 

 

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Briggs & Stratton generally replace to trade anything found to be faulty in manufacture. Honda take it personally and tend to infer they don't make mistakes. Cultural thing? Nev

 

 

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Hmmmm hmmm um hello anyone... Anyone know the cost of having the through bolts done by a Lame. Oops i mean LAME

 

Alternatively whats the cost of sending it to Jabiru and having them do it?

 

 

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I would want to know how many times he had done the job before,, and depending on the time in the engine log book it might be worth doing other things at the same time. I think some engines have to have bigger dia bolts/studs fitted . This would be a totally different situation to "normal"..Nev

 

 

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I would want to know how many times he had done the job before,, and depending on the time in the engine log book it might be worth doing other things at the same time. I think some engines have to have bigger dia bolts/studs fitted . This would be a totally different situation to "normal"..Nev

I wonder if there is, in reality, a 'normal' situation? We know that the operational experience of Jabiru engines varies widely - some operators have grown to routinely expect problems after 300 hours or so, while others get trouble-free lives of 1000 hours. We have the experience of both private and commercial operators with such discrepancies to draw upon. Some engines are never touched by other than an L2/LAME while others are owner-maintained exclusively. Some operators use 100LL and nothing else, some use whatever they can get at the time. We know that different people have different ideas about what is the best oil to use and what plugs give best performance.

 

We also know that some people have what may be called 'mechanical sympathy' - or perhaps that should be called empathy - while others do not. I'll place a small bet that there is not one member of this forum that does not know people who can sense that something is not quite right with their car (or aircraft) while also knowing others who will wonder what that scraping noise from the brakes is while driving on worn-out brake pads that are chewing the disc to pieces (for instance). If the latter class did not exist, I doubt there would be much call for road-side assistance from motoring organisations, by way of example.

 

Then there are those who by nature are not of 'an enquiring mind' regarding their mechanical device: yes, they do what the book says, but don't want / believe a need to go beyond that. Indeed, the book 'Zen and the Art of Motorcycle Maintenance' elegantly discussed the difference between those who do not want to be 'involved' with the operation of their mechanical device, they just expect it to do what is written on the packet when they turn the key. You put money in at one end and get performance at the other - correct? Well, to a fair degree that is not unreasonable - but it assumes that all the operational aspects of the use of the device also conform to the limits imposed for the use of the device and it is very easy for those limits to be exceeded in something as (relatively) fragile as a small aircraft, where every ounce of added robustness has its cost in performance.

 

So I think it is realistic to assume that different owners will approach their maintenance in different ways - some will use the opportunity of a re-build to address all known problems, do everything up to 'ticketty-boo' standard, while others just do/have the mandated work. I have a Jab. engine that EFATOd through broken through-bolt; one 'estimate' for the re-build was 'around $2.5 - $3K, while another (a very well-respected Jab. engine re-builder' stated that he 'won't do anything less than the best possible job on personal principle') and I'd be looking at between $6 and $8k. I have absolutely every confidence that the latter quote was no in any way an attempt to gouge the market, but an honest appraisal of what it was likely to take to turn out a Jab. engine that is as bullet-proof as it is possible to obtain.

 

Why the difference, and is that reasonable? Well, I used to be involved in racing motor cars, and it was common practice for 'production' car racing to 'blueprint' the engine - which meant nothing more than making sure that every part was exactly to the best fit to the production specification: all pistons weighed the same, all rods weighed the same, the cylinder head volumes were identical, little intolerances in production were removed etc. For a Holden 351 V8 motor in the 1970's, that cost was typically of the order of $5k for a brand-new, off the shelf, never-run engine - and it was worth up to around 40 horsepower and racing-level reliability. It wasn't a 'hot-up' - absolutely everything had to be within manufacturer's stated limits. Someone like Harry Firth would spend literally hours going through tubs full of pistons and rods to find a set of eight that were identical when assembled.

 

Does anybody think that the Red Bull racing aircraft just bolt in any old Lycoming and go out to do battle? Dream on.. and yet, relatively speaking, we use our Jabs. routinely at a level of performance/weight/cost that is not so very different - for every take-off! Do you think the Red Bull Racers just roll up to the pump and say 'fill 'er up' and head off? - I doubt it, but many of us pour in whatever we have been able to buy, check it for water, and hope for the best in terms of its current (age-dependent) RON/MON, the presence of additives/other contaminants of which we may be unaware etc. Never had a load of 'dirty fuel' in your car? - then you probably don't drive beyond the city.

 

Much of what is in a Jabiru engine is purpose-built by equipment which is very much state-of-the-art (it's a real experience to look inside CAMiT at the manufacturing of one, if you haven't seen it, it's a real eye-opener); however the cost of a Jab. engine also reflects the use of mass-produced 'commercial-grade' items, such as the pistons. Jabiru just doesn't have the volume of production to be able to have everything produced to its unique specification, so it's a cost-balancing exercise and yes, sometimes there will be failures. That's a risk you have to accept if you spend Jabiru-class money on your engine, and in the main at least, Jabiru will pick up the tab if it's demonstrably their fault.

 

I note (and though I somewhat tongue-in-cheek suggested that Rotax does not 'warrant' the 912, of course they do) that in reference to a Rotax being 'the gold standard' - Jabiru offers exactly the same hours (200) of warranty as Rotax, though only for one year vs. 18 months. Rotax is a part of Bombadier - a company that has just spent nearly $3Bn. on developing a new aircraft, vs a company that sells, what - a few $m worth of aircraft and engines a year? Did you see the recent attempts by VW to deny any recall of their cars that were, in effect, EFATO-ing on the road? Does Ford routinely replace the faulty differential and rear brakes on Falcon utes that are now well out of warranty? Every company has its limits on accepting liability for its product.

 

Could Jabiru engines be better? - yes, of course they could - but what is the magic level of cost/weight/performance/reliability that would be generally accepted?

 

 

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"though only for one year vs. 18 months" - two years since 2008

Evidently Rotax did not know that: see: http://rotaxnews.net/?p=268 As of Dec. 31, 2011. it was still 18 months, but you can get an extra 12 months and 200 hours at a price.

 

 

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Fair comment Oscar. Your experiences are similar to mine. Why someone has a vibrating engine and continues to fly it , amazes me. It will rarely, if ever "FIX" itself. ( An exception being icing, but you have to act on it). I still and always have believed that the through bolt problem is detonation. Never have I heard anyone consider a colder range of spark plug. The company have lowered the compression ratio. Stale fuel is always a possibility, though I would not think the avgas would go OFF like some Mogas does. When I fly in a jabiru I am not sitting there just waiting for the engine to fail but if the temps go up I climb at a faster speed. There are quite a few things I would do to my own Jabiru engine if I had one but I won't go into that on line here. Jabiru's recommendation are reasonable. A lot of the problem seemed to happen when they tried to lean the engines out. Were they trying to get endurance for DRONE s? Nev

 

 

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. Were they trying to get endurance for DRONE s? Nev

Well, funnily enough, the Jab. 2200 engine was selected by Boeing for installation in the Israeli drone that they were trying to sell to the Aus. military (but that whole project folded, though no fault of the engine!) - and one of the requirements was, as far as I can remember, constant idle in preparation for take-off for something like 30 minutes at something like 32C! In a pusher configuration without even benefit of prop wash. for cooling...

 

I happen to know that the aero engineer involved in trying to sort that one out, found out a whole lot more about Jab. engines than any owner would ever want to know (and he has a long, long history of working with Jab. engines, from their very start.) He believed it would be achievable, though I don't know if he actually got to the point of demonstrating it before the military changed their minds. Amongst the things he found was that in a crosswind, it is possible to get reverse flow in the downwind cooling plenum i.e. no useful airflow past the cylinder heads at all! If the downwind baffle happens to be the one on the side without the CHT sender (since standard Jab. installations only have one cht sender), I'm pretty sure it is quite possible to exceed the CHT limits for that side of the engine without ever knowing it. I'm not across all the numbers here, but the margins are not large.

 

 

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I knew they were into that stuff. Forced fan cooling would have to be done. I also thought endurance (range) had to be extended. Nev

 

 

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Oscar

 

Sorry my post was a bit brief - it was meant to indicate that between 2007 when a friend purchased his Jab and 2008 when I purchased mine the Jabiru warranty increased from 12months to 24 months [still 200hrs]. It wasn't intended to indicate a change in the Rotax warranty.

 

 

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OscarSorry my post was a bit brief - it was meant to indicate that between 2007 when a friend purchased his Jab and 2008 when I purchased mine the Jabiru warranty increased from 12months to 24 months [still 200hrs]. It wasn't intended to indicate a change in the Rotax warranty.

Frank - I guess they've been a bit hurt - it's given as 12 months on the Jab. website as of the moment! I wonder if the decreasing widespread general availability of 100LL (and hence the necessity to accommodate MOGAS) is the reason behind that?

 

 

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Was not aware of the return to 12 months, should have looked.

 

Just had a look.

 

Engines advertised 200hrs / 12 months

 

But if you buy a factory built aircraft

 

2yrs / 500hrs.

 

 

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Was not aware of the return to 12 months, should have looked.

Just had a look.

 

Engines advertised 200hrs / 12 months

 

But if you buy a factory built aircraft

 

2yrs / 500hrs.

 

Interesting. I just had a look at the site for one of the more popular Rotax-engined aircraft - Pipistrel - which states:

 

The warranty on Pipistrel aircraft is 12 months or 100 hours whichever comes earlier. The airframe is covered by Pipistrel, the engine is covered by Rotax

Sting aircraft: 2 years/ 100 hours.

 

For Tecnam I couldn't find any warranty information. Flight Design provided in 2012 an extended warranty on the Rotax, to 3 years / 500 hours, whichever comes first. For a mere US$143k (current exchange rate makes that about A$152) - vs. a J120 with brand new engine (not reco) with a 2-year/500 hour warranty, for A$63k.

 

So Jabiru is certainly well up towards the top of the class in terms of its customer support for factory-build.

 

 

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Guest Andys@coffs

Home Truths about warranty's:-

 

1) A warranty is worth the paper it is written on only if the manufacturer actually does what they say they will do and in doing treats all in good faith, seeing a warranty as a precious commodity that can enhance sales rather than be a drain on profitability!

 

2) If the disclaimers in the warranty in word content are greater than the word content about the benefits of the warranty then its my opinion that caution needs to be exercised!

 

3) How's this for a warranty (a joke, not real and not actually offered) I warrant that a single player will win Lotto at least once if they play the same numbers in one game for each unique draw occurring not more frequently than once per week for 45,360,620 consecutive draws. In the event that doesn't occur I will pay $1m in restitution. Player must be the same natural person for all 45,360,620 unique draws, and be able to provide proof of continuous entry across the 45,360,620 unique draws and present any claim for restitution in person.....For clarity relatives of the person or a non living person are specifically disclaimed from applying for the restitution. This warrant exists only until such time as the means to provide perpetual life is discovered where upon it immediately ceases. The $1m restitution is constant and unadjusted for the effects of inflation and will be paid in Iranian Rials or alternately Australian Dollars where an exchange rate of 24,000 IRR = 1AUD must be applied first....

 

 

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Andy - so damn true...

 

I am sure there are some on this forum who class me as an apologist / champion for Jabiru. I suppose to a degree that's correct - I have sufficient faith in their products to have put my money where my feelings lie and bought one; beyond that I have no 'interest' ( such as could be termed a 'conflict of interest in a Court of Law) in their products.

 

However, I - and many others, of course - have some knowledge of the Jabiru 'story' from their start, and I have the added advantage over some of knowing just about all of the people seriously involved in the creation of Jabiru aircraft and engines. Without exception, those people are all persons of very great integrity in their professional life - they genuinely care about their customers. That extends beyond just the concept of 'product liability'.

 

It's no accident (no pun intended!) that Jabirus have an excellent record for their airframes - they are forgiving, tough, reliable. They are pretty damn cheap to repair, too, for even quite serious levels of damage; where carbon fibre is used in structural members and suspect damage virtually mandates replacement,because of the difficulty and complexity of damage-testing for c/f. They don't have nasty aerodynamic vices and they bounce pretty well from incidents common in the conditions we have here in Australia (including gust speeds that are fairly extreme in world terms). You get a pretty decent amount of aircraft and capability for the money.

 

Jabs. are not the performance leaders, though I'm not aware of anything else in the LSA area that will actually cart the volume of stuff you can shove in a J230 around happily at a decent cruise speed/economy ratio.

 

Something has to be compromised to achieve a balance between cost (purchase, hourly running cost, repair cost), usable load, performance, safety, and abuse-tolerance. As a matter of personal preference, I am prepared to accept that my Jabiru engine requires a degree of attention to use limitations that is more restrictive than those one can get away with with say an O200D or a Rotax 912 (though I have deep-seated reservations about a crankshaft manufacturing technique that is ok for lawnmowers and go-karts and can twist between journals alarmingly and catastrophically: see: http://www.atsb.gov.au/publications/investigation_reports/2007/aair/aair200700054.aspx

 

Jabiru and CAMiT are working together on improvements. Expect encouraging news in the fairly close future!

 

 

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Yeah . I've never got my mind around the pressed up crankshaft either, in the 912. The Jabiru crank is oversupported main bearing wise for the power output, but I guess they were trying to build it strong. Nev

 

 

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Yeah . I've never got my mind around the pressed up crankshaft either, in the 912. The Jabiru crank is oversupported main bearing wise for the power output, but I guess they were trying to build it strong. Nev

Pressed up cranks are fairly common as you would know, and I can't see where you could possibly doubt the longevity potential with the 912 crank (and whole bottom end for that matter ) as they have already proven to possess that typical German bottom end quality and long term robustness. Like the old stock VW or Porsche engines, if you've managed to destroy the bottom end the rest of the engine is going to be in very poor condition indeed.................Maj...011_clap.gif.c796ec930025ef6b94efb6b089d30b16.gif

 

 

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I do a lot of work with pressed up cranks Maj (as you know) When you run roller bearings they are pretty much unavoidable if you want optimum life from the big ends, but the trend is away from them elsewhere. That aspect of the rotax is a puzzle to me. It reduces the size of the crankcase a bit, and lightens the conrods but it is an unusual feature. I'm wondering if they planned a roller bearing motor.? Nev

 

 

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