SonexBuilders.net

bvolcko38 wrote:What size O ring are guys using between the needle carrier and the screw? also what material type? Butyl? nitrile? viton?

I have a big metric set of Buna-N O-rings, and I just picked whichever one seemed to fit best. Maybe 4mm OD x1mm. It just needs to be big enough you can get it over the little ball head and thin enough that you can still assemble the carrier. Since it's not sealing anything, it's not very critical.

I hadn't posted this a few weeks back ... so here's a pic of what I did to keep the needle from coming full lean out of the slide. Put in a small set screw.

I'm still waiting for details on Chris from Australia set up with fuel injection, which was on the pod cast. It sounded so simple and made the engine run great. Anybody hear anything?

Chris and I have been working very hard on our electronic fuel injection setup and have it running reliably.
There have been some teething problems with selecting injectors with just the right flow rates that satisfy maximum demand, low physical profile and control in the most efficient range of the injectors operation.
We have been refining the manifolds and fuel rails to make them light, compact and simple to fit whilst reducing any points of possible failure.
The redundancy feature of the design works like a dream which means you can switch between naturally aspirated and injected in flight with confidence.
You would appreciate that every time we try a different set of injectors, we can be required to make new fuel rails to fit with the varying physical dimensions of the injectors being tested. Add this to the fact that Chris has been very sick for some months (improving now) and progress has been slow. However, we are very close now.
We are keen to share our final results with the community and to this end I have been developing a web site that will have all our findings and construction details for others to follow.

Hope this clarifies the current situation. Please stay tuned.

FYI , the Rotec tbi I had so much faith in failed at 91 hours,,,,,,,went super lean in flight to the point of the motor detonating badly and basically stopped....With my backup fuel pump and primer over ride and a mixture setting via trail I managed to get down safely but I was very lucky... so back to the devil I know. I have reinstalled the Aerocarb.

Hi all,
Brett, sorry to hear of your troubles with the rotec. do you have a mark 1 or 2 rotec tbi?
also are you aware of the diaphram upgrade for the primer/regulator? John gillis had an engine out in his jab3300 waiex with the rotec tbi. that really got my attention, also on the vans site, a few others had the same experience. rotec came out with an upgraded diaphram design. they sell it on their website as part of a complete tbi overhaul kit. $175. plus shipping.
florida sonex, thanks for your post on the modify you did to your aeroinjector slide. anyone with an aeroinjector ought to take a look at his mod to keep the needle from coming out of the slide and going full lean . a few others have posted on here of the same problem.
thanks to all that posted on their rotec/aeroinjector experiences, hopefully better awareness and knowledge will keep the community and fleet safe.
i did upgrade to the new rotec diaphram design, and will explore more on intregrating a facet electric pump into the fuel line.

WaiexN143NM
Michael

Mk 2 Rotec it was.

hi brett,
just a couple quick. questions, if you will. how old was your mark2? and did you know of the upgraded diaphram design? the o ring is now molded into the diaphram filment, and a different pin design.
glad to hear you made it back ok.


WaiexN 143NM
Michael

I bought the unit around about April 2016...

I’d say I have the old Diapham setup as it seems to have no o-ring moulded in.

I went back to the Aerocarb. Its primitive and requires you know its limitations, but its simplicity is its strong point. Just gotta adjust mixture a lot.