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Jabiru mixture


Yenn

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Jabiru emailed me today touting their new mixture control. They have a you best electronic gadget that will inject air into each inlet manifold to ensure the mixture is correct for all stages of flight. It is fail safe they say.

 

Given that Jabiru have used the supposedly automatic mixture control carbide for years, are they saying that the carbide is not efficient, or not reliable? Either way I would rather replace the carbide with the injector produced for Stones.

 

 

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reads OK but considering their strong opposition to EFI over years its surprising to see them present a microprocessor controlled unit

 

Fail safe back to std carb is what many EFI systems use too.

 

 

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My doubts are the injection of air could result in detonation on take off if the fail safe fails. The standard of construction doesn’t inspire confidence, those screws standing proud look amateurish to me. I haven’t been game to look for a price,but I bet it will be several hundred dollars. 

 

There was someone in the USA modifying the standard carries to give manual control 

 

 

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My doubts are the injection of air could result in detonation on take off if the fail safe fails. The standard of construction doesn’t inspire confidence, those screws standing proud look amateurish to me. I haven’t been game to look for a price,but I bet it will be several hundred dollars. 

There was someone in the USA modifying the standard carries to give manual control 

Looks a rushed assembly with counter sunk metal treads sitting proud where round heads would be the ideal fastening.  I'd guess they didn't have any round heads available at the time.  Look forward to hearing how the units go in service.  Cheers Mike.  Bye the way how did you get on with having 'Rodds Bay' included in your airfields name.  (I see the CQGC airfield at Dixalea has (McMaster in brackets)  and that's great to include the local name which is in Alan's honor.

 

 

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Don’t u rabbits realise this is a Jabiru April fools joke that was a day late.

 

Did anyone really think that modified school boy 3D printed pencil box with wood screws could perform such a magical job.

 

Got u all talking though.

 

Happy APRIL FOOLS  day

 

 

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Don’t u rabbits realise this is a Jabiru April fools joke that was a day late.

Did anyone really think that modified school boy 3D printed pencil box with wood screws could perform such a magical job.

 

Got u all talking though.

 

Happy APRIL FOOLS  day

Nobody told "Australian Aviation" magazine then... 

 

http://australianaviation.com.au/2019/04/jabiru-aircraft-working-on-new-engine-technology/

 

This product seems to me, to bring the WORST of both worlds.

 

The inefficiency of a carburator fed engine and electronic control.....

 

If you're going electronic, then be done with it and fit full blown fuel injection and deal with the benefits and problems of it.

 

Otherwise stick to carby fed without any electronic trickery, for better or worse.

 

By taking the middle ground you're getting none of the fundamental benefits of either....

 

 

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So Rod fooled us, but was it April 1st?

 

Concerning Rodds Bay. It is YIVG, but as they say, that is so we don’t mistake it for the body of water, miles away. Funny that Rodds Bay is closer on the chart than YIVG.

 

I have told Airservices that Miriam Vale is no longer an. Airstrip, since it was planted to eucalyptus forest. Should I also tell them that Facing Island would be a bit wet, or that Agnes Water is not quite as high as they say it is. The whole setup inspires ridicule rather than confidence. All caused in my opinion by CASA wanting us to use area frequency, rather than 126.7 which Airservices didn’t want as it put more load on their radio use. Personally I think using area was the safer option so I need to juggle 3 frequencies on my climb out, or approach.

 

 

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  • 2 weeks later...

I thought it was about time that we found out more about this piece of equipment, so I phoned Jabiru. I was put on hold while the receptionist found someone who knew about it. That took a couple of minutes or so. Then Daniel came on the phone. He didn't seem to know much, said it is still being developed and works of an EMS such as Dynon. Inputs are EGT, RPM, MP. etc. Cost still to be decided, so I didn't bother putting in an order for one.

 

I did think it was most likely an April fools joke, but if so they are taking it a bit far.

 

I use a Jab engine and so far am happy with it, but this doesn't inspire confidence in Jabiru. The whole premise appears to be off. If the carbie is so bad that it needs a control like this, it would surely be better to use a different method of getting the mixture to the engine. Maybe I should have asked to talk to Rod or his daughter who is now the boss. 

 

 

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As I interpret this:

 

There’s no control over the carby. 

 

Essentially the carby does its thing and the device uses the CHT and EGT etc to detect which cylinders have temp changes and from these deduces that the rich cylinders can be leaned by injecting air so that the temps can be adjusted to bring them all close together. 

 

Again some assumption on my part. 

 

To make the system work properly you would have to rejet the carby to make the hottest one ( presumably the leanest one) still not too lean because this system can’t make a lean one rich only drag rich ones down to match a lean one. 

 

Assumptions on my part.

 

 

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