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Jabiru 3300 - Leak Down Test Results


ryan4321

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It is a good price and I have been told by the LAME that previous tests were 75 on the cylinder that were showing 48. He said it is quite variable and if a leak down was done again it should be okay again. He also mentioned it was likely the rings (ie not valves or other) so it isn't as significant also.I have factored in a new CAE 3300 engine also in the pricing of this one so if I get 100 - 200 hours I will be happy :)

Sounds like you have made your mind up already.

You did ask for advice and mine is not about the technical aspect, there is a problem with the motor that has been identified, does the LAME offer a valid reason (if there is such a thing) for why the pressure would change?

 

There have been many replies here saying buyer/flyer beware so the choice is yours.

 

Cheers

 

 

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You are being taken for a fool, as a LAME and Jabiru owner ( 2 of! one with 4cyl and one with 6cyl) if I saw numbers like that the engine would be pulled immediately. That engine needs work before it can be classified as airworthy. The LAME in question is referring to continentals which have a very broad definition on leak down tests. Jabiru's don't! If you are keen include the cost of a rebuild in the purchase price and make it a condition of sale. Experience with these engines had led me to start searching for an issue when the leakdown a hit 70/80.

Hmmm, From another source, I have been told NEW jabiru 3300 engines are sent out if their leak down test is 70 or better. So I am a little confused when you say that you will be searching for a issue below this?

 

The issue I have been told is with the rings causing the lower reading.

 

 

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Hmmm, From another source, I have been told NEW jabiru 3300 engines are sent out if their leak down test is 70 or better. So I am a little confused when you say that you will be searching for a issue below this?The issue I have been told is with the rings causing the lower reading.

Ryan, I dont know how to say this without it coming across as being bad. You asked for advice and you dont like the answers. People here have been honest with their advice including mine. Take it or leave it and find a pilot willing or not to ferry your aircraft. Good luck.

 

 

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Hmmm, From another source, I have been told NEW jabiru 3300 engines are sent out if their leak down test is 70 or better. So I am a little confused when you say that you will be searching for a issue below this?The issue I have been told is with the rings causing the lower reading.

Deadstick has had a fair bit of experience with jabs and jab failures, I would take his word over most others ESPECIALLY someone who was involved with a plane that was being sold.

As for what's let out of the factory I won't go there.....097_peep_wall.gif.dcfd1acb5887de1394272f1b8f0811df.gif

 

 

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A new engine could be expected to improve with use. An older one there is not such an expectation. (unless it's been sitting and a boroscope examination of the bores should be done in that case before running it. If the rings are the source of the lost compression it is easy to verify and should have been done by checking what comes out of the breather. Valves not seating likewise will be heard in the exhaust or the inlet as appropriate. It's not as easy to check the inlet but it is also less likely to be a problem in service. Nev

 

 

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I'm sorry it may have come across the wrong way - but there are a lot of opinions and I don't take any 1 persons as gospel and it is a matter of trying to find a good consensus basically as I don't have anyone's detailed history / experience level on here. It is nice to know though that 'deadstick' is has a lot of experience with these planes.

 

The person I has spoken to regarding the value of 70/80 being the lower limit of the Jab factory letting new engines out to pasture was a trusted source (I would assume) as he has built a J400 and also rebuilt a damaged J430 so he also has a lot of experience in the past (and present) working closely with the Jab company.

 

The LAME who has looked after the sellers plane for years I think was also quoting values from Lycoming engines as he said that the leak downs on previous tests had been around 75 ('from memory') which I had been told was a load of BS from the contact person I had above as he then referenced the lower limit for new Jab engines being (70/80) and it would be near impossible for it to be 75 on an engine with 480 hours (or even 200 hours after new valves / heads etc.. which is this engines history). So I think the LAME just made a mistake with that reference.

 

All in all - Negotiations have progressed and I now have this J400 at a great price and am looking to eventually refit with a CAE3300 engine, so I will have our local LAME here give it the okay before getting some hours up on the 'old' engine before the swap over. If he says it's on the fritz I will just have to splash the cash earlier than desired for the new engine.

 

Thanks everyone for the advice & guidance!

 

Here's hoping the CAE engine is a winner!

 

 

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Guest Andys@coffs

So...at the risk of being pedantic 48/80 is a fail, 60/80 is a pass, by a microscopic amount........The engine as is, is unserviceable and cannot be flown......when the engine is fixed then you can, as you say try to get those extra few hundred hours........I hope that getting 48 back up to 60 is part of the sale agreement, if not those few extra hundred might well be fairy dust, or lotto wins, oft talked about but rarely seen.......

 

Here's something you can do right now...get down on the ground and look up at the belly behind the exhausts.....Much oil on the belly? If its spotless you need to fly a close in circuit (with the expectation of engine fail....etc etc) to get it up to temp so you can do the leakdowns while hoping for that miracle non intervention cure....also oft spoken of, little seen as well.....when back on the ground repeat the belly inspection......if theres quite a bit of oil there then, or at first inspection, you may well be in a world of hurt......

 

Andy

 

 

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Good luck. There really wasn't much point in asking the questions if you had no intention of listening to the answers.

 

With the current Casa ruling on Jabiru engines, why anyone would buy a suspect one and hope to get a couple of hundred hours out of it rather than an immediate change out absolutely amazes me. Hope my Grandkids are not in your Flight/Landing/Crash path.

 

And as for Camit I think they may have some answers, pity is that at the moment they are struggling to deliver engines, or I would have bought one.

 

 

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I would imagine people with Jabiru engines would be running out of sense of humor by now Nev

No Nev not at all. I still have my sense of humour. It is sitting on the floor of the hangar right alongside the Jabiru motor that came with the cheap airplane that I just bought and didn't try to get 200 hours or TBO out of. 015_yelrotflmao.gif.6321765c1c50ed62b69cf7a7fe730c49.gif

 

 

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Seriously - this is criminally insane - this is an example of a problem that can't be put on Jabiru if the engine fails and suffers a force landing.

 

The engine displays clear cut signs of a problem and yet is being considered adequate to continue to fly let alone feel that an additional couple hundred hours is possible. Quote from the Jabiru service manual - "Maximum allowable pressure loss is 25% - therefore a differential of lower than 80/60 indicates a problem. " 2 cylinders are below specification and 3 more are so close it is not worth splitting the difference. There is a problem and it needs to be addressed. If the rings are gone it is going to be down on power and throwing oil out the exhaust as well burnt contaminants and heat back into the sump ruining the remaining oil.

 

The LAME should be beaten with a stick and have his licence revoked for signing the engine off as being okay. Has he even read the Jabiru manual? And sorry Ryan, you are a fool for attempting to fly this aircraft without the problem being rectified. It is a case of negligent maintenance, pilot error and poor judgement reflecting badly on an aircraft manufacturer when the maintenance manual is ignored.

 

You can argue all you like that Jabiru should be able to make an engine last longer but it is negligent to fly when a maintenance inspection shows a problem.

 

 

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As he said first job is to get another maintainer to look at it

 

If the price was right and new engine planned is OK

 

Get someone with experience to clear leakdowns first, id suggest they were done incorrectly or cold. It would hardly be running at 80/40 and oil use would be significant.

 

Just because someones a LAME doesnt mean hey are capable on all aircraft. Ask him to sign a maintenance release for it.

 

 

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I am happy that someone experienced with Jabiru engines is going to inspect the engine before the aircraft is continued to be used and if necessary replace the engine if there is a problem but it has to get there first!

 

How is the aircraft going to get from WA to the Sunshine Coast to get Ryan's local maintainer to look at it without putting the ferry pilot at risk of an engine failure onroute? Making the assumption that the pressure test was done incorrectly before a 24 hour flight is not the wisest of decisions.

 

 

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Ryan was the one who said he was going to get his local LAME (Sunshine Coast) to look at it (aircraft currently located in WA) which I would presume he meant that he was still going to fly it back to the Sunshine Coast to do so - refer to other posts looking for a ferry pilot. If I am wrong and Ryan was going to get it checked in WA before flying back then that is a wise decision. The engine needs to be checked before such a flight - even just to prove that the current test was done incorrectly, but critically to ensure that the engine will last and not kill the pilot in a forced landing on the way.

 

I am not arguing with you jetjr, I am just concerned that an engine which has tested out of specification and is in serious need of further investigation and/or repair could be flown across the country with great risk of an engine failure if the word of the current LAME were to be blindly accepted.

 

 

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AVOCET ( in my humble opinion) If it needs an inspection, it would need it at the beginning of a cross Australia trip There's plenty of country out there where you wouldn't last a day without shade. If you have made a decision to do the trip, and the plane hasn't had much use for a while. inspect the bores for rust and do some flying locally where there is plenty of suitable landing places and you can pick your days to fly and monitor the engine. You can turn it over by hand if you know what you are looking for to get a feel for the compressions. If any of them deteriorate you make plans accordingly. Nev

 

 

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When I originally bought my Auster it had an impeccable history on the leakdown tests - all around 78/80. However, I got an annual done before I took delivery and one cylinder had dropped to 37/80 - the aircraft had not been flown much in the previous year. Turned out to be corrosion in one valve cause by sitting - as well as a loose valve seat. The history of leakdown tests is just that - history - what it is now is what matters. We got the cylinder done immediately and has been perfect since.

 

I know its not a Jab motor but these things happen in all

 

 

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Doe

 

AVOCET ( in my humble opinion) If it needs an inspection, it would need it at the beginning of a cross Australia trip There's plenty of country out there where you wouldn't last a day without shade. If you have made a decision to do the trip, and the plane hasn't had much use for a while. inspect the bores for rust and do some flying locally where there is plenty of suitable landing places and you can pick your days to fly and monitor the engine. You can turn it over by hand if you know what you are looking for to get a feel for the compressions. If any of them deteriorate you make plans accordingly. Nev

doesnt hert to pull over and have a check at the half way mark Nev .

Anyway , i could do with a visit .

 

Mike

 

 

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Ryan, sorry if my comments have come out harsh, but:

 

  • one it makes no sense to ignore obvious signs of a potentially major problem that could put yours or someone else's life at risk; and
     
     
  • secondly, because as a result of the restrictions put in place by CASA to counter the issues with Jabiru engines, some of which may have been avoided by people listening to the signs predicting failure (and yes, as well as Jabiru doing a better job to stop the problems from happening again), I (and a large number of other Jabiru owners) have lost a lot of privileges, access to trusted LAMEs, access to local airfields and multiple financial losses with rental income, student training and value of their aircraft.
     
     

 

 

It is worth taking the advice of people who know well the problems that can occur, the signs of those problems and how to best avoid the serious consequences if the problem does occur (and not me since I am still learning what can happen but there were several very knowledgeable people here who have given you advice to be careful).

 

 

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