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Jabiru Bad experience

Old 19th Jan 2014, 23:26
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Has anyone got any ACTUAL Statistical Facts on the Jabirus? So far we all seem to be relying on either:
A. "My mate Barry from down the road and myself both own a Jabiru and they both had engine problems, so it can't be our fault!!"
OR
B. "Well, mine has run alllll the way to TBO and I'm running it perfect so it must be the fault of the people using them..."
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Old 19th Jan 2014, 23:55
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i thinks thats half of the problem, there is little in the way of facts, as once failed components are sent to Jabiru, they are never seen or heard from again. no reports, nothing.
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Old 19th Jan 2014, 23:59
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Hi XXX,
sure its the usual default to blame the operator and I can assure you that your not the first. If I am doing something wrong then the POH needs amendment, Both my Jabs are fitted with full CHT and EGT monitoring, and the overheating event was indeed a climb out issue where number #4 skyrocketed above 200c with a CFI and an instructor at the controls.


I will paste the history of the J160 from the CASA defect report up for a read.


XXX, I didn't join PPrune to Slag off a company, I have been on here as a viewer since 2011, I retired from the military due an injury after 10 years as an aircraft engineer and 10 as a Pilot, I am working as a LAME at the moment and like to think I know the pointy end of a plane from the blunt.


I posted the info on every website I could find as I believe its a first hand account based on fact, If I save one person from making the same mistake as me then I will be happy.


I'm sure your post wasn't personal, and I respect your objective view but I can assure you I will no longer go along with the factories poor record.
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Old 20th Jan 2014, 00:02
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History: the aircraft was purchased from Leaseair PTY LTD by me at 1318.0 ( post through bolt failure).
Prior to my ownership the engine was sent back to the factory at 1100 TTIS ( 15/08/10 for a top end overhaul due low compression and TBO, on its return and after install and runin it was fine, up until 1200.8 (100.8 TTSO) when it was noted to be weeping oil around the base of the barrels and the orange sealant used on either side of the shims was peeling away.
A call was placed to Jabiru (Don I think, called me chief) who informed that it is not U/S pending a successful torque check of the through bolts, which showed nil movement.
I was informed that the cylinders could be lifted and more orange sealant applied if it was bothering me I noted that it was just a clean up issue to the owner and it was elected to put up with the weeping.

At 1314.6 TTIS (214.6 TTSO) a pilot annotated that it did not make minimum static rpm (As per POH) so after the usual checks the carburettor was removed and serviced with corrosion under the bellows being found, this was discussed again with the factory the corrosion treated and the jetting checked, post reinstall it would still not make static RPM and I was advised that it is fine and that the factory was releasing an amendment to this requirement.

At 1318.0 (218.0 TTSO) the engine suffered an inflight through bolt failure of number 2 Cyl and was put down in a paddock, subsequent investigation revealed that The SB for the through bolt nuts had not been carried out and the time to comply had just expired 29/04/12.
Prior to release of this SB the through bolts were discussed with the factory ( the engine had only just been installed, post Top end at the time of the weeping problems) and the advice was that all engines would be done whenever they were returned for major service and not to worry about it.
So leasair elected to leave it as is and no reference was made to the SB again until after the failure! our mistake!!!

Post failure the engine was inspected, repaired, new T/Bolts, new #2 piston and cylinder, heads visually checked re-lapped and engine run in.

At 1351.2 TTIS (251.2 TTSO) number 2 Cylinder exhaust valve was leaking past the seat, the head was removed and it was noted that there was cracking and pitting around both inlet and exhaust seats so it was rejected and a new head purchased and installed.
A bore scope revealed none of the same on the other cylinder heads...

At 1475.6 TTIS (375.6 TTSO) the engine dropped an exhaust valve seat whilst sitting at idle prior to takeoff on first flight of the day, luckily the seat wedged sideways and was retained buy the valve sticking open and slightly impacting the top of the piston.

Upon disassembly (see pictures) the other two older heads show signs of the valve seats moving, the engine has never been over temped the heads show no abnormal signs of cylinder creep, it has CHT and EGT on each cylinder and the dynon EMS log showed it has always been within limits.

Other things noticed on disassembly:
1. locating dowel under the distributor drive shaft was not installed correctly and was eating into the shaft slightly.
2. Sump had a 2 inch piece of cylinder O-ring rubber sitting at the bottom and the usual carbon, a few pieces of metal.
3. the sump flange had a ding in it at the same location that it used to weep ever so slightly.
4. #4 cylinder head intake runner has a crack forming down the face of the valve boss.
5. lots of excess flange sealant inside the engine.
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Old 20th Jan 2014, 00:13
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interesting

interestingly I just received and email from a member of a UK jabiru forum, apparently its common knowledge in the UK that the generation 2 cylinder heads crack between the inlet and exhaust ports. This may explain why Jabiru refuses to return my heads after I stated that I would like an independent report as I didn't think their explanation that a leaking exhaust on one head caused all to overheat in the exhaust valve area, co-incidentally the business manager had no knowledge of heads ever cracking before!
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Old 20th Jan 2014, 00:49
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the overheating event was indeed a climb out issue where number #4 skyrocketed above 200c with a CFI and an instructor at the controls.
393 deg Farenheit = 200 deg celcius.

This is a standard Jabiru CHT gauge; note the markings.



So you say that an instructor lett his happen? Normal operating temps are 275f / 135c

With all due respect I would consider taking your aircraft offline from that flying school.
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Old 20th Jan 2014, 00:54
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Deadstick 1
I'm interested in what type of CHT sender probes you have. Is it a washer under the spark plug type or a screw into the head type?
Robert Gutterage spent a fair bit of his Oshkosh forum showing the very different readings produced by two different systems.
Cheers RA
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Old 20th Jan 2014, 01:05
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XXX, POH states top of green arc is 180 degrees c, and operations above that up to 200c for no longer than five minutes. The aircraft has full CHT and EGT on all cylinders and a flashing light on the display once a cylinder exceeds 180. The CFI stated to me that it happened so fast the light flashed grabbing his attention and he watched the temp rocket through 200 within the time it took to advise the Pilot in command as soon as the throttle was reduced to idle the engine began running rough and they declared a PAN and conducted a glide approach to back to the field, subsequently the engine stopped just after touchdown. These guys are very professional and of note was the fact that all other cylinders stayed below limits. There was no evidence that the EMS sender on that cylinder was faulty but it was replaced anyway and was discounted by the inspector. They could not find anything wrong with the cylinder that would suggest leaning out but I relayed my concerns about the intake plenum to tube design that relies on an o-ring and goop to seal.
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Old 20th Jan 2014, 01:06
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They were the washer under the spark plug type during this incident but I have since changed them to the latest configuration of a screw in the head between the plugs.
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Old 20th Jan 2014, 02:10
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Have you noted any variation between the temp readings you are now seeing and those you saw with the original system when flown under similar conditions?
Cheers RA
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Old 20th Jan 2014, 02:52
  #31 (permalink)  
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Yeah but its a new engine and an slightly different duct, it runs about 20c cooler across all cylinders
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Old 20th Jan 2014, 03:16
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Hi DeadStick, I've re-read your independent report elsewhere and have continuing thoughts on the issues that you have experienced.

It appears that crankcase fretting has occurred due to a loss of torque of the engine thru-bolts which were subsequently replaced under the documented SB for Jabiru engine thru bolts.

Did you maintain this aircraft engine the whole time since new?
Did you / whoever check the tension of the thru-bolts at any time that you were maintaining the engine?
Why didn't you present the engine log books to Jabiru or the independent third-party company that you engaged to review the teardown?
When were the thru-bolts replaced?

The Jabiru service bulletin was released in April 2011 where the thru-bolts had to be replaced, however your independent report was from March 2013.

For engines under 500 hours the compliance was within 100 hours or 12 months. For engines over 500 hours it was 200 hours or 12 months.)

Without the log books for the engine there is no evidence of correct maintenance at all and for all anyone knows, the engine may not have had correct maintenance.

If you were take this to an appeals tribuneral, fair trade, consumer affairs or a court of law, you'd have no evidence by which to support your case.

That's just the thru-bolt issue. Then there's the heads cracking. You have identified that 3 heads have cracked and failed. The Dynon engine monitoring instruments keep detailed information on engine performance and store it to a SATA hard drive for quite some time. Was this information reviewed in conjunction with the preparation of the report?

The report has also stated that the temperature on one head reached 180c and therefore the headS are considered scrap. This would indicate that the over-heating condition was not just limited to a single head as you've identified that your CFI reported.

I'm not getting a clear picture of the true story based on the evidence provided and feel that this is nothing more than the result of a vexatious falling-out between you and Jabiru.
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Old 20th Jan 2014, 03:26
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You wouldn't happen to be trying to unload one would you 3X?
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Old 20th Jan 2014, 04:01
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Nope. I just like to see a balanced argument with facts from both sides rather than just a one sided social media / forum slagging campaign. (It's a pity we don't have Jabiru here to defend themselves) The nett result of these campaigns is that once a company goes broke you won't have to worry about thru bolts or heads because you will no longer be able to buy them! It's not like you can buy Jabiru heads from Superior !
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Old 20th Jan 2014, 04:06
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Small apologies there DeadStick but your post #24 didn't appear until just now which answered some of my questions possibly because when you posted it you were still a probationary user.


It all makes sense now that you mentioned where the aircraft came from. I wonder if yours was ever based at Bankstown. I recall a thread about some 160's at Bankstown a few years back.
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Old 20th Jan 2014, 04:10
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The CFI stated to me that it happened so fast the light flashed grabbing his attention and he watched the temp rocket through 200 within the time it took to advise the Pilot in command
About the ONLY thing that can cause this kind of action is a preignition event, usually from a cracked ceramic on a spark plug. Or a tiny slim chance of a helicoil tang protruding into the head.

Jab heads do not have helicons (or they did not long ago) so a spark plug, most likely dropped caused this. Rough mechanics?
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Old 20th Jan 2014, 04:30
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...hey I was wondering where you have been Jabb Dabba Doo, we need yr expertise here buddy

"Deady" you don't need to justify or explain anything to anyone here buddy, you posted yr experiences of said jabajunk & if anyone was going to buy such a 'thing' then it's up to them to take ALL info in
If I heard just one tiny bit of bad info regarding any product I would then do my own homework, not listen to anyone else experiences trying to cover up what you have had.


Wmk2
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Old 20th Jan 2014, 04:58
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Yes, i was at the controls when this particular engine fried.
It happended within a few seconds and there wasnt much i could do about it.
I am a little tired of hearing about the "operator error". Look dudes, the FACT is, this plane was always operated within the specs of both the maintenance manuals and the flight manuals. It cooked in seconds and has yet to be fully explained.
If this failure was some sort of random out of the blue failure then I wouldn;'t have much more to say about it. But its far from random, the donks are rubbish. Pure and simple. yea sure, blame the operator or the maintainer, but sooner or later this Jabiru copout will have to be answered to with facts. When you do try this you are greeted with the sort of underhanded BS that deadstick has posted here.
The simple solution for my school has been to go back to a real aeroplane engine. And low and behold.....problem solved... No more random failures and rubbish factory attitudes.. Just constant, reliable, trustworthy performance..
Sorry jB, BUT WE TRIED TO USE YOUR PRODUCT. BUT IT FAILED ..MISERABLY..
PS. having operated half a dozen of these things over multiple years in a variety of conditions, i believe my statements are backed by actual experience, and not just hearsay etc.
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Old 20th Jan 2014, 05:02
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I should add, I was referring to the J230 engine overheat. Not the4 J160 with the lemmon engine.
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Old 20th Jan 2014, 05:03
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Motzartmerv, any idea why the log books weren't sent to the engine facility and third party engine inspector?

It's like sending in your car at 80,000kms with no books and asking for a warranty claim on the engine.
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