Took an hour today to start cleaning up the push rod tubes that I removed from each of the cores:
First step was removing the old dry and cracked o-rings. GM used simple rubber ones which in the conversion process are replaced with Viton rings. Viton doesn't dry out with heat and remain supple over the course of the engine's life. Some were already cracked and missing pieces:
I rummaged around in my tool box and found the perfect thing to use. Don't ask me if I know how sharp the point is:
Some came off complete, but most came off in brittle little pieces:
Next step will be to clean them up. First a bath in Simple Green to get rid of the grime and grease, followed by a polish. The tubes are made of light steel with a zinc coating. GM left them bare, but standard practice for conversions is to paint and bake them white with high heat enamel to enhance cooling (or at least reduce heat transfer to the tubes from the cylinders). I've read online it's best remove the zinc coating and this can be done using an aggressive Scotchbrite pad or bench grinder wheel.
I haven't posted anything to my blog for a couple of weeks because I've been busy doing the other things in life that keep our family hopping at this time of year. Vacation, two birthdays, two anniversaries, the end of the school year, fireworks shows for Canada Day (another hobby of mine) and some camping. All this happens in the span of 14 days. But it's over again for another year.
Of course my mind hasn't strayed too far from my project and I'm starting to narrow down my decision on what airframe I want to build. In my post from last year "So Many Choices" I describe my thought process in this regard.
Just before I started vacation, I managed to meet up with Ron, a local home builder who has vast experience with building aircraft from scratch, from kits and rebuilding damaged airframes for others. He is currently working on a Piper Pacer, but he has offered me a spot on his build team and more importantly, the opportunity to assist him and another guy in building a Zenair 701. You can't ask for better chance to learn from someone that has "been-there-done-that". Ron is also keen to see a Corvair installation process, perhaps for future build of his own.
So, after much debate and thinking out the pros and cons I've decided 99.9% that I'm going to begin the process of building a Zenair 750 STOL (Short Take Off Landing). This aircraft has the best of everything I'm looking for:
One thing I really like about the home building movement is the willingness of others to share what they have learned and help others get started. It's a tight knit group of individuals and it's great having that support network when working through a build.
During my vacation, I got a call from another Corvair builder named John who is putting a Corvair in his Zenair 650. His engine was built for him by William Wynne and he is close to flying his 650 for the first time. He reached out to me after seeing I was also in Ontario in hopes of having another Corviar builder to bounce ideas off of (again, that built in support network is great). He also offered to put me in touch with yet another Corvair builder who is doing the same 750 airframe that I'm interested in.
I told John I was planning on heading to the Zenair open house being held in conjunction with the Midland RAA (Recreational Aircraft Association) fly-in being held this past weekend. We agreed to meet up in person and that's exactly what happened yesterday.
I arrived at the Midland Huronia Airport sharply at 9am Saturday morning. I was hoping to meet the Zenair staff before the crowds got too busy. I had the opportunity to speak directly with brothers Michael and Nicholas Heintz, sons of Zenair aircraft designer Chris Heintz. I explained my goals and mission and they answered any question I had. When I mentioned I was planning on putting a Corvair engine into the airplane, they were very positive about the combination which is extremely encouraging.
Michael advised me that a builder from Newfoundland by the name of Jeff Moores was coming that day to look at purcashing a Zenair 750 and was a Corvair builder as well. I've had conversations with Jeff via the Corvaircraft forums, as he has already built a Corvair for his Merlin ultralight, so it was great to meet him and his wife Dale in person. Shortly after, John walked over and introduced himself.
Jeff, John and I talked at length about each of our plans and how we are at substantially different phases of the build. having built both a 2.7 litre and 3.0 litre Corvair engin, Jeff offered some great insight to the differences and advantages of each. Considering none of us had ever met before in person, it amazed me how quickly we became friends - guess that's all part of being a builder.
We took a tour of the production facility where Michael explained the evolution of Zenair kits and how advanced the CNC production has become, even just in the last few years. The 750 kits are considered state of the art and are "match drilled" meaning all the holes in the pre-formed aluminum parts are already drilled for the builder, saving substantial time in assembly. It was clear from the tour that the kit quality is top notch, and I came away from the tour feeling very confident that this is a great project for an amateur builder like me.
As the morning progressed, each of us were offered a flight in the factory 750 demonstrator with Nicholas Heintz. This one is actually the 750 Cruzer model, which has a somewhat cleaner airframe (no slats, different wing, etc) resulting in a somewhat faster cruise speed than the STOL model, but the cabin dimensions and "feel" are the same. The demonstrator is equipped with a Jabiru engine (which is has approximately the same horsepower as what a Corvair would:
Now, I'm not sure what my goofy smile was from; the fact I was actually going flying or how pleased I was to experience the visibility this cabin design provides (and I wasn't even in the air yet!) but I suspect it was a combination of both:
A short time later and we were airborne! I was so wrapped up in the flight experience and speaking with Nicholas about the handling characteristics of this Cruzer model vs the STOL version, I didn't get any puictures, but I am really impressed with this aircraft. Smooth, stable and comfortable. The visibility is incredible in all directions and the bubble doors give that extra feel of roominess. One thing I noticed when I had the controls and entered a turn was the really nice visibility through the clear panel cabin roof:
Jeff's wife Dale took some pictures and videos of my flight and when they get a chance will send them to me and I'll post them. Here are a couple of more I took:
So things are starting to pick up speed. I'm definitely in the arena and the game is about to really get started!
Husband, father and 911 dispatcher. Long time pilot with a licence that burns a hole in my pocket where my student loan money used to be. First time aircraft builder. Looking to fly my own airplane.