Aerocarb/Aeroinjector discussions

[sonex892]

If your worried about the burps and you have a jabiru. There is always the bing that came with it.

My fuel system is stock standard Jabiru style setup with a bing. That is Gascolator, mech fuel pump, airbox with carb heat. Gascolator is mounted to bracket welded to the engine mount in an effort to isolate it from firewall vibrations. The only insulation is on the flexible lines from gascolator to fuel pump to bing. They are covered in firesleeve

It is a bit more work initially, but. I have never had to tinker with anything apart from the idle mixture and the idle setting. 111 hrs now and never burped. Economy doesnt seem to suffer from using a bing. I average 19lph at 130kts at 2700rpm. Thats 5 US gallon per hr @ 150mph.

Steve Sonex 892
VH-ZSX

[kmacht]

Not sure if it is related to the aero-carb burp or not but there was recently a Sonex that had a forced landing here in Connecticut. I only know what was reported in the news papers here so unless the pilot posts on here what exactly happened take the facts with a bit of skeptcism. The plane was being flown by a second owner (not the builder) and had the Jabiru 2200. They were 10 miles from the destination airport after a mid length cross country flight. The engine quit and they put it down in a marsh. Fortunatly it appears that the pilot walked away with minor injuries and the pictures seem to show the airplane with very little damage.

The interesting parts is that the news sources are saying that the FAA was able to restart and run the aircraft engine at the landing site before it was removed. I originally thought this might have been a classic fuel starvation issue or maybe a broken crank but since they restarted the engine it sort of rules that out. Two other possiblities stick out in my mind. The first is carb ice and the second is this "burp". If it is the standard aerocarb the carb ice seems unlikely due to its design. If it was due to the burp then I am a bit more concerned. I'm not familar with the bing carburator but I do belive it uses a standard venturi and is susceptible to carb ice. The whole thing sounds very similar to Jeff Schultz accident. Does anyone have any more specifics on what happened or know the pilot involved?

Keith
#554

[MichaelFarley56]

Here's a quick link:

http://www.kathrynsreport.com/2012/08/s ... uries.html

Looks like the plane is more or less okay. These are always tough...could have been a fuel issue, or maybe a failed ignition coil. Has anyone talked to the pilot?

[revlis240]

I have been trying to figure out what happened to Jeff shultz for a while now. Tragic story, but he wont respond as to what he thinks happened. Would love to know the cause of the CT forced landing. They say carb ice is unlikely with the aerocarb, but it seems this is the second time that an engine with it has quit on decent!

Abe

[Nqsonex]

Hi all
This is an account of our recent experience with aerovee powered sonex, whilst on a first longer flight in hot humid temps about half way into the flight and upon ascent to get over a mountain range the engines started to misfire and the progressively get worse, eventually it wasn't,t producing usable power so a suitable emergency landing site was found in a farm and subsequent landing performed, there was no time to get to an airfield but fortunately the plane was landed with no damage.

The plane was dismantled and returned to the airfield then reassembled that same day.
The fuel was checked and all was found to be ok.
The plane was restarted and no defect had been found, all checks were performed and the engine runs as normal.
Only conclusion is that it has vapour locked due to the hot weather.
We share this in the hope that we can save others from his event, the outcomes may to be as good.
We are attempting to cool the whole fuel system down to stop this happening again.

[MichaelFarley56]

That's a very interesting story. First off, I'm very glad that you were able to find a landing spot and had an uneventful landing. That's always first.

With regards to the vapor lock, if you could take a few moments I'd be interested in some additional information. First off, do you remember the weather conditions at the time? Mainly I'm interested in the outside air temperature, and how high you climbed before you started losing power. Do you remember what your engine temperatures, such as EGT and CHT temperatures were? How did you have your mixture adjusted and did mixture changes help or hurt the situation? I wonder if its possible that, as you climbed, your engine continued to run richer and richer until it started misfiring.

Has your engine been running well since?

Please keep us up to date on how things go. I've flown my Aerovee in temps in the upper 90's during this summer and the only time I have issues is during idle after I land, which I can manage with mixture adjustments. I would strongly recommend a fireproof sleeve over your fuel line in the engine compartment, along with covering your gascolator with an insulation.

Thank you for sharing and keep us up to date on further testing.

[Nqsonex]

Hi mike
Yes definitely glad to get it down in one piece.
As for temps they were all still in the green, the outside temp was approx 31c, and about 90% humidity, both egt,s and cht,s were under max, the height attained was only 2500ft, also leaning was tried but only made the situation worse.
The carby had been tuned for summer recently and until now had been running fine, this is the first longer run for the summer months, it has done about 20 hrs over the last 2 months.
As for the fuel plumbing there is an exposed alloy pipe that exits the firewall on the pilots side and runs across the firewall to the exposed gascolator then to the aerocarb, it is now going to be rerouted and fire sleeved to see if this helps.

The plane hasn't,t been flown as yet, only found testing has been done and all seems fine, no issues under any load up to full power.

Will keep you all posted, just an issue we don,t wish to see again for obvious reasons, to date the aircraft has done approx 140 hrs total, mainly in the cooler times of year.

Cheers

[142YX]

Thanks for posting your story. If you have any available, would you mind sharing a few photos of your fuel line setup from firewall forward? I think building a database of specific installations that have both been proven to work, and others that have caused problems will be a great asset for the community.

[Nqsonex]

Hi all sorry for the late reply, I haven't any photos of the original install, since now it has been altered.
Since rerouting the fuel lines and also shielding better, there hasn't,t been an issue with the engine, it has run faultlessly and put under all conditions that you would expect vapour locks.
A definite must for all those installing there own fuel lines, make sure that it is shielded well, there can't be enough emphasise put on the ramifications of a bad install.

Keep safe all
Nqsonex

[fd38]

Has anyone tried an electric fuel pump, i.e. Facet, in their fuel system? This frequently solves vapor lock. And if so, where mounted, etc? They do make low psi models. Thanks.