SonexBuilders.net

Who has the most hours on their Aerovee with and without overhauls?

Steve Stahl
Waiex. N54YX

Bump to the top for my friend Steve.

I'll start out. 0.0 hours and counting.


Come on guys, I've seen lots of posts about how many hours you have on the AeroVee.

I'll take the lead for now. I flew my AeroVee for around 70 hours, did a rebuild as part of raising compression and some other modifications, and then flew another 60 hours before I started tearing back into things for the turbo upgrade. Once complete, I'll have new connecting rods, cylinders, pistons, heads, and the turbo. I didn't split the case so I guess it won't be considered a overhaul; maybe a rebuild.

I believe that Tony Lewis had around 750 hours on his aerovee before upgrading to the 6 cylinder Jabiru.

Keith
#554

That's great!! Any others?

Steve
Waiex N54YX

Had 120,000 miles on my bug before I pulled the engine for a rebuild. About 60k of that was hard driving delivering pizzas in the late 90s. Still ran but it was marking it's territory a little too much and the clutch was slipping. Teardown revealed the heads were cracking between the intake and exhaust valves on both sides and the case had been machined so many time prior that it couldn't be saved. Ended up starting from scratch.

So at an average of 40mph that would be...3000 hours.

Know that doesn't help much in the context here but that was my only car at the time. I have a lot of faith in the aircooled VW. I drove them exclusively for close to 20 years. If you adjust the valves, change the oil, and don't over and/or under rev them. They just keep running.

I'd like to resurrect this thread for fun and curiosity. Let's see if we can get more post this time, post again even if you did before with updated numbers.

Thanks!

I'm also really curious also about what hours people have on their engines from new. Besides routing maintenance of course

Required "rebuilds" I think are few and far between. And how do we define an "overhaul?" I think the kernel of the question is how reliable is a VW airplane engine, and how often do we need to do something major to it? I have never seen any quantifiable information that makes me say one VW engine is better than another (Great Plains vs Sonex, etc). Lots of personal opinions, but not much empirical data. So I'm inclined to lump most VW's together. That said...

My VW is not an example of precision German engineering. It's a wonderfully basic, simple engine that can take a licking and keep on ticking. And if it breaks down it is SUPER simple to fix. And CHEAP to fix. Believe me, I know about both of those.

At my first annual I found I had low compression in two cylinders. To make a long story short, I had run the engine too lean for too long (from my maintenance logs, about 25 hours of run time) and burned a couple of valves. Operator error. I had mismanaged what my instruments were telling me about the needle and settings I was using on the AeroInjector. Hint: if your engine is running hot and you are burning only 2.5 gph, then you are too lean! Quit doing that! It was not the fault of the VW, it was my lack understanding of the AeroInjector, and my slowness to actually do something about it. Once I changed the needle and got everything to about 4.5 gph, I have had a very happy engine. I have had ZERO issued with the AeroInjector since. I had a local engine guy replace the valves, after buying the valves from Sonex. The guy charged me $50. Try that with a Lycoming or Continental!

I had 124 hours on my engine before it became obvious from oil samples and some other evidence, that there was trouble with the aluminum Nickasil cylinders. They were being crushed by the heads and the engine was making more and more metal. I took off the cylinders and replaced a lot of parts. Because of the metal in the oil I had to tear the engine down to FULLY clean everything!
Retained: Case, crank, conn. rods, cam, heads
Replaced: Bearings, cylinders (cast iron), rings, wrist pins
None of this was the fault of the VW engine. It was the weight-saving cylinders that were not up to the task (I have my own theories why).

From 124 hours to 150 hours the engine ran like a top. ALL the numbers were better than the original build, including CHTs.

Then I had a bad day. I freak gust of wind picked up my tail while taxiing, and I had a catastrophic prop strike (one blade was found 200' away). I replaced the crank, bearings, prob hub and cam gear (though later inspection showed I did not need to replace the cam gear; I was just being cautious). To do all that I had to open the case. To my insurance adjuster the cost was a joke. He couldn't believe a new crank only cost $350.

Again, none of this was the fault of the VW. My engine has never failed (I just knocked on my wood desk!). It even kept going when the original cylinders were in hideous condition. So I HAVE rebuilt my engine, but NOT because the tried and true VW did anything to require it. I now have 230 total hours on the engine without any further issues. I change the oil and get an oil analysis religiously. I gap the valves and check all my connections.

So what is the common thread here? The engine has never failed, even when I did bad things to it. By doing regular maintenance checks and oil analysis I have been able to find every problem before it became an engine stopping event. And when I did have to "rebuild" or "overhaul" the engine, it was from operator error and not from a failure of the VW. And the costs were almost laughably low for aviation.

Since my last "rebuild/overhaul" at 150 hours (prop strike) I have had 80 hours of awesome engine operating numbers. I hope in another 200 or 300 hours I'll be able to revive the thread and report that I've not done any more dumb things to my engine, and haven't needed a "rebuild/overhaul".

I wouldn't worry too much about the hours. It's been my experience with VWs that people tend to over analyze and second guess themselves too much. Regular VW (car) owners lectured me for years on how they can't be daily drivers. Up until a a couple years ago, I drove aircooled VWs daily for almost two decades. I never had an engine blow up on me or suddenly cease to run. I've had issued that lead to rebuilds but I saw them coming from a mile away. Change the oil, adjust the valves, don't abuse it, and they just keep going. For the record, it wasn't the dependability that drove me to "modern car" it was the lack of effective climate control.

While I'm not an Aerovee owner, I can see the similarities between Beetle/Bus owners and the Aerovee owners. Many people (both the cars and planes) tend to sweat too much about every little issue. This leads them to tinker too much and get frustrated. They seriously don't need to be perfect in every way to run just fine for a long time. While some things might be bothersome (small leaks and such), they're not going to effect the engine's ability to do its job. I've had most of my VW engines run close to 100k before they started showing serious problems (2000 hours) and they were spinning an average of 3700 rpm most of the time.