Siezed low-time neglected turbocharger

[Brett]

I love the performance of the turbo setup. Not just the actual take off performance but the lower overall cruise speed noise when setting say a 25-26" map setting at about 2500 rpm and seeing 110kts. I can't help but want to see the project work. If I had the benefit of hindsight I would have bought a Rotax but now I've spent so much time, money and heartache I'd like to actually make it work before I'm forced into that situation. My thoughts at this stage are just going on my own. I like to think the factory have tried diffenent turbos and settled for this one for a particular reason other than low unit cost. My first thoughts I suppose would be to ask a turbo supplier in Australia if they can match up this configuration or turbo in a straight oil cooled version with a old school journal bearing and carbon seal and hope the extra oil flow doesn't drop the oil pressure below min requirements for the engine. Then comes the worry about foaming of the oil I suppose that was a big issue in the development of the turbo kit. I really dont' want to go down this experimental path alone but what choice apart from rebuilding a turbo every 20 hours in its current configuration. Probabky what will happen if problems still continue as one day there will be no turbo for sale on the website any more. Ask for advise and the answer will be "What turbo?"

Downhearted at Christmas
-Brett

[Sonex1517]

Michael Farley is correct. I removed the turbo and am now flying behind a normally aspirated AeroVee.

If I had the money for the new mount, prop, carb, and accessories, I would drop a Corvair 3.3L in my Sonex today. I do have a core I am puttering with and hope to build up, but after rebuilding the AeroVee, buying new heads, intake, exhaust, and oil pump, plus replacing my prop (twice), I confess that all I want to do right now is fly it.

Long term, I am torn between a Rotax for reliability - there is a lot of Rotax knowledge at my airport - a Corvair because I believe in them - or a Jabiru 3300. I like the idea of a new engine in the UL, but am not fond of the requirement for electric power to run my engine.

Again, no money for this right now. All of these solutions involve much more than just an engine. Personally, I am just very, very disappointed in Sonex for how they have handled this.

[daleandee]

I DO love the sound of that 6 cylinder Corvair, the price is in the right ball park although it is a bit on the heavy side. I guess we need to see more of them flying and see how they stand up after some higher flight times.

I do love the sound of the Corvair myself! As to how the Corvair stands up to higher flight times ... there's a lot of information on the web about Corvair engines and a good number are now flying as Cleanex aircraft although the owners are not either a part of this group or choose not to post here. Mine is still relatively low time at 166 hours but I would make the same choice again. I've never flown a turbo VW conversion but did own a non-turbo tri-gear for nearly 200 hours.

As to Brett' post about figuring out a way forward by himself ... that would be my approach. 1st I'd look to find a conventional oil that would take the heat of the turbo. I mentioned before that I have a lot of good reasons for preferring Rotella T4 conventional 15W40 for my flat tappet Corvair. I use it in my VW engine also. Some have stated that it is good for up to 300ºF but I have no way to confirm that. It is used in hard working turbo-diesel equipment that runs extremely hot at times.

As for lead of the 100LL reacting with the semi synthetic or full synthetic oil there may be a work around. Is the use of 100LL because the turbo requires higher octane? If so what number does it need? The reason I ask is because it may be possible to mix some Mogas with the 100LL in manner that lowers the lead content and still leaves enough octane to satisfy the requirements of the turbo engine.

For example ... my Corvair needs 93 octane. Many times I can find 93 Ethanol free but at times I can't. Lately I've only been able to locate 90 Ethanol free Mogas. Mixing in a little 100LL brings the octane level back up but reduces the lead content dramatically. This is not convenient when flying cross country but does work at my home airport where I have the option of mixing fuels. A fuel mix a calculator can be found here: http://www.wallaceracing.com/octane-mix-calc.php

Dunno if this helps:

Dale Williams
N319WF @ 6J2
Myunn - "daughter of Cleanex"
120 HP - 3.0 Corvair
Tail Wheel - Center Stick
Signature Finish 2200 Paint Job
166.7 hours / Status - Flying
Member # 109 - Florida Sonex Association

[WaiexN143NM]

Hi all,
Merry christmas, good weather out here on the west coast.
Good luck to all getting your turbos working properly.
As for engines, i think it would help sonex out to at least offer different motor mounts for the onex. Rotax 912, UL260/350 , jab 2200/3300,. Builders would be on their own for fwf, cowling, baffeling, prop etc. builders doing some mods of existing kit components. Along the lines of selling more airframe kits.
VW parts quality seems to be in question. As we outsource mfgr outside the good ol USA , quality seems to be a problem. Brasil, mexico, china.

WaiexN143NM
Michael

[Brett]

On a selfish wish list I love to see a 912 conversion mount from a standard VW mount but I can't see that happening. :)

I'm still hoping for a long term reliable turbo installation. I don't know how much tech info would be supplied to the owner in this regard but I see no future for that turbo in its current config. I have been trying to look at ways of water cooling it but weight and complexity always brings me back to a more suitable tubo model.... let's see what the new year brings I guess.

[Waiex 49]

I never tried the turbo AeroVee so I can’t speak to the turbo related issues, but my experiences with the normally aspirated AeroVee were not all that wonderful. I pulled that engine off my Waiex after an exciting engine out landing.

Just my opinion, the Sonex is a good airframe in search of a good engine.

I’d love to see the Sonex company providing more support for alternative engines.

Merry Christmas (and safe flying) to all.

Don Bowen
Viking Waiex N49YX

[kmacht]

Don. What was the cause of your aerovee failure.

Keith
#554

[Brett]

How many turbo aerovee installations are still actually flying? Not sure if I'm being pig headed by continuing to make it work or tenacious?

[Waiex 49]

Hi Kieth,

I’m not trying to slam the bug motors, just saying I wish the folks at Sonex would be more supportive of engines other than the ones they sell. But I guess if it isn’t a problem in Wisconsin then it isn’t a problem.

I purchased my Waiex in flying condition and the motor ran fine for a while. Then it started leaking oil from several locations, CHT’s ran hot, I had problems with both ignition systems and the Aero Carb started throwing fits. Just when I thought I was making progress with these issues I was on a short cross country flight and an exhaust valve rocker arm broke and the motor stopped cold. I blame it on cheap parts from China or Brazil or where ever it is that Sonex sources their stuff.

I was lucky to be right over an abandoned Naval Air Station with two 7,000 foot runways. Landed “dead stick” without a scratch to the airplane or myself. I was very lucky to be over friendly territory!

I like the Sonex airframe but wish the folks at Sonex would more actively support other engine options.

It’s a good airframe in search of a good engine, in my opinion.


Don

[dbdevkc]

Robbie,

Where did you find your Corvair core? I've been searching for a while now here in the northeast and have yet to find a usable engine. A couple close calls but the wrong case codes.

Kevin