And down goes another jab.

[Sapphire]

I would give every nut and bolt I could access a good feel up.Don't forget to include your pitot tube

[damkia]

I would give every nut and bolt I could access a good feel up.Don't forget to include your pitot tube

(Great sig line)

 

[Sapphire]

We went a longg way on pitot tubes at another thread

 

 

[ahlocks]

I'm as slack as you'll ever find but I still decowl, eyeball and shake the bejezuz out of things before first flight. Seen quite a few Jab drivers do the same too. Not sure what to make of it all really....

 

 

[motzartmerv]

Yea that's all great stuff.. You could pull what ever you like off, things like this are impossible to detect without removing other sh|t. Some things you just have to trust are going to stay together.

 

 

[motzartmerv]

How many hours has it been since the last oil change, i.e. inspection? You mentioned it's done about 40hrs since being fixed up, so I'd assume only about 15hrs since it's last service?

.

Yea it would be something like that. I am 300 miles away from the school so info is slow to come back to me.

 

 

[Gentreau]

We have a standard practise to remove the top cowling and make a full visual check at least daily too.

 

We check the engine mounts, all hoses, plug caps, electrical connections and safety-wires.

 

In France we don't have the L1, L2, L3 qualifications, every pilot is 100% responsible for his or her machine which is why we don't trust anyone else to have done anything, we check ourselves.

 

I don't know the Jabiru engine, so I didn't know that the intake manifold is not visible from above.

 

Sounds like those bolts should be safety-wired.

 

 

[geoffreywh]

Hmmmm. The only way for the inlet manifold bolts to come out is if they were only finger tight in the first place ( we are talking about the alloy machined part with the six inlet tubes coming out of it aren't we?) And, If I remember, you can't get the centre rear one out without taking off the exhaust muffler cover first. The manifold halves will sit in place together as they have a couple of dowels ( or maybe just one?) to line them up and cannot fall off due to the exhaust cover. IF bolts like that are loctited and done up properly they will NEVER come loose by themselves. Someone just forgot. It can happen. ...........I don't see that taking off the top cover helps much unless you take off the air scoops as well. You can't see much at all. Geoff (L2)

 

 

[motzartmerv]

Taking the top off is really only gunna help with the blaring obvious. Leads off, loose scat hoses, choke cables ,Oil leaks n such.

 

Pilots of school acft can't do anymore than that. While privateers can do as they please we are accountable and can't undo a nut.

 

 

[ahlocks]

.. we are accountable and can't undo a nut.

No problemo then Motzy, looks like the nuts undo themselves anyway! ()

 

 

[geoffreywh]

they are not nuts!...................... 1/4" cap head screws

 

 

[brilin_air]

Hmmmm. The only way for the inlet manifold bolts to come out is if they were only finger tight in the first place ( we are talking about the alloy machined part with the six inlet tubes coming out of it aren't we?) And, If I remember, you can't get the centre rear one out without taking off the exhaust muffler cover first. The manifold halves will sit in place together as they have a couple of dowels ( or maybe just one?) to line them up and cannot fall off due to the exhaust cover. IF bolts like that are loctited and done up properly they will NEVER come loose by themselves. Someone just forgot. It can happen. ...........I don't see that taking off the top cover helps much unless you take off the air scoops as well. You can't see much at all. Geoff (L2)

Or the inlet gaskets have compressed slightly being new and the bolts haven't been checked since it was o/hauled

 

Brian

 

 

[ahlocks]

they are not nuts!...................... 1/4" cap head screws

Bugger.... "Running a spanner over me cupheads" just doesn't have the same appeal.

 

 

[motzartmerv]

Or the inlet gaskets have compressed slightly being new and the bolts haven't been checked since it was o/hauledBrian

Or there is no gasket. That too is missing apparently.

 

 

[eightyknots]

I was taught to always remove the cowl and do a thorough under cowl engine inspection as part of a daily. And I know others that learnt to fly at other schools have been taught the same. Personally, I think it's a good idea and plan to keep doing so.

I have to do an under-cowl inspection in the Piper Super Cub every time I fly her. It's the flight school's rules.

 

 

[Sapphire]

I had an unusual issue with a 0-200 Continental carby. A lever attached to the throttle cable at one end was held at the other end onto the throttle shaft with a nut and secured by a split pin. The lever and throttle shaft flange faces were serrated so when the nut tightened the two together they fit together like two gears would mesh. This prevented the two from slipping and changing throttle position. [most of you are falling asleep by now, but I am getting to the punch line] You tighten down the nut for the right throttle position, put in your split pin and think that job is over but the nightmare has only started. Slowly the nut worked slightly loose and unscrewed to the limit the split pin would allow. With pressure the throttle adjustment could be changed leaving you with idle power, full power or something inbetween. Similar result with going to idle on Bing carbys but for a different reason.

 

 

[ahlocks]

Perhaps we're locking down on examples of and the importance of a good preflight and missing an opportunity to chase up on a potential quality control issue with the manufacturer that may have occurred. An unbiased investigation to identify if there has been a break down in the system of work is a win for both manufacturer and end user if a problem exists that can be identified and corrected. Besides, it's much more fun pickin' on Jab owners when there's nothing actually wrong with the product.

 

 

[Heavy Metal]

I tell you what, Im over this. My satellite schools J230 clapped out on crosswind today in Goondiwindi.The instructor took over and got it down on the crosstrip. No problems.

An initial inspection showed that the intake manifold had "lost" its retaining bolts. They just simply were missing. Not sheared, fractured or broken. Just absent.

 

Has run for a bout 40 hours since a factory bulk strip.

 

The very flight before this one was a solo student, 15 years old.

 

Ive had enough.

[Riley]

Or there is no gasket. That too is missing apparently.

So Motz are you telling us that it was returned from a factory bulk strip with no gasket installed under the inlet manifold, or is it meant to be a metal-to-metal face seal? Only back in the air 40 hrs - small wonder you're a trifle pee-ed. Like Alice in Wonderland, this gets "curiouser and curiouser". cheers

 

 

[Sapphire]

Besides, it's much more fun pickin' on Jab owners when there's nothing actually wrong with the product.

Are you serious?

 

 

[Heavy Metal]

Hi Every One,

 

Reading motzartmerv post reminded me about an article I read about a pilot who went down in his Jab.

 

If you have not read it you may find it interesting???? The link is: http://www.jabirucrash.com/

 

Take Care!

 

 

[ahlocks]

Are you serious?

One can dream....

 

 

[motzartmerv]

Perhaps we're locking down on examples of and the importance of a good preflight and missing an opportunity to chase up on a potential quality control issue with the manufacturer that may have occured.

Yea my sentiments exactly. I mean finding loose or missing bolts in this area of an engine in a pre flight or daily??? Some pretty optimistic ideas coming across. We all check gudgeon pins in cylinders too??

 

Yes so far it looks Like no gasket. The boys can't locate it or any sign of it. I'm just getting info in as they find out.

 

 

[Sapphire]

The development of the 1600 Jab engine involved relatively few hours. Something like less than 100hrs on a test bench and about half that stuck to the end of a plane. It and other Jab engine developments took and takes place as a result of "feedback" from pilots who have had engine failures. They call that "tombstone technology". Though that happens to various degrees elsewere. Qantas nearly lost an A380 and wing cracking is becoming an issue. You have to look at how much testing is done before the product is is unleashed to the public and how much of a guinnea pig the public have to be.

 

 

[Gentreau]

.... I mean finding loose or missing bolts in this area of an engine in a pre flight or daily??? .

Clearly if the area is inaccesible, then that's not going to happen. If the fixings are cap-head screws then I guess they can't be safety-wired either.

 

Is there a requirement by Jabiru to use any kind of thread locking compound on these screws ?