Friday, May 30, 2008


In the building of any airplane, the acquisition of an engine has to be among the most important moments. Today, I bought an engine.

The history -- if not the tradition -- of homebuilt airplanes is scrounging old barns in the country looking for dilapidated planes, finding an engine therein, and then through the guile and guts of the builder, figure out a way to make it work on the airplane being built.

Screw that!

I don't know anything about engines, frankly. If the car breaks down, the only thing I really know how to do is open up the hood and stare, occasionally fidgeting with stuff for no other reason than if I were to be kicked out of the American Society of Guys [tm], I'd have to start watching Ellen on a regular basis.

And screw that, too!

So I called Mahlon Russell at Teledyne Mattituck Services on Long Island.

I'd previously decided -- generally speaking -- on what sort of engine I needed, when I ordered the finishing kit from Van's Aircraft. I needed to have that decision made because a specific motor mount is required.

And so this is where we started today's conversation:

  • A 180 hp engine (360)
  • Fuel injected
  • Parallel valve
  • Vertical inductioin (Ah, you also have to have this decided when you order a finishing kit because it requires a little scoop on the engine cowling that comes with the finishing kit.

    Granted, I place myself at the mercy of a business when I say, "Hello, I'd like to buy your product and I don't know what the hell I'm doing!" But, Mahlon (that's him over there on the right with me at the RV Builders BBQ last year that I put on.) has a reputation for service and helpfulness (not to mention: honor), and as I've written before, I've generally placed myself in the hands of fellow RV builders whom I respect and followed many of their recommendations blindly.

    So here's what you need to do to buy an engine after you get to the part described above:

  • Constant speed or fixed pitch. For non-pilots, propellers can be made to change pitch in flight (constant speed) or made to be only of one pitch. The advantage of the former is more performance when taking off, the ability to slow down faster for landing, and the ability to set a more efficient setting in cruise. The down side is it's one more cable to install, it's much more weight to carry and, oh yeah, it costs a hell of a lot more.

    As I'm building what I call "a working man's airplane," and since I've never flown a constant speed prop, and I figure I can save fuel just buy keeping the plane light, and I fly out of nice long runways, I went with fixed pitch. However, I ordered an engine (after Mahlon described the options) for an engine that is set up to work with a constant speed prop with a number of tweaks, but comes ready for fixed pitch. My rationale: Even if I decide never to convert to a constant speed prop, the fact the engine CAN be converted gives it more resale value. The cost? $200. Deal.

  • Ignition system. Standard is magnetos. Again, for non-aviators, it's a time-honored system that doesn't require an electrical system to provide sparks to your spark plugs, which make the crankshaft turn, which turns the propeller, which keeps you in the air. But electronic ignition can be more efficient, though it does, then, require some dependability on the electric system in the aircraft.

    Other folks I know have gone with one mag and one Lightspeed electronic ignition system. There are other options out there including E-Mag (they're really good guys but the sense I have is that the product just isn't quite dependable enough for an idiot like me) and a full FADEC system, which costs about $8,000 and computerizes everything -- pretty much like your car.

    The cost alone eliminates the FADEC option, my stupidity eliminates the E-Mag, and those other RV builders that I mentioned early, made me lean toward a Lightspeed Plasma and one Slick Magneto approach.

    "What kind of flying are you going to do in this plane?" Mahlon asked.

    "I'm a go up and look down kind of pilot," I said. I fly pretty much around Minneapolis-St. Paul, underneath the Class B airspace and I plan to take an occasional cross country trip back East or Texas or Florida or the Bahamas or San Francisco.

    "So would you say for every cross country, you'd fly about 25 hours local?"


    "At what altitude?" he asked.

    "Probably an average of between 3,500 and 4,500 above sea level," I said.

    He then said that a Lightspeed doesn't give you a lot of efficiency at those altitudes and doesn't really give you anything until 6,7,8,000 feet, leaned out and then you can get 10 or 15% efficiency.

    But, again, there's no penalty -- except a little bit of weight -- for using the electronic ignition other than the $655 additional it costs, and I figure that's still a small price to pay for both the option of me doing a different kind of flying, and the resale value of the plane. Deal.

  • Roller tappets vs. standard tappets. OK, remember the part about me being stupid? Good. Just read that section again. Roller tappets (pdf)are a fairly recent attempt by Lycoming to addresssome problems with camshafts. They basically heat up and break -- see above about what a camshaft is connected to.

    The roller tappet eliminates the sliding motion between the cam and tappet,improving wear and allowing the introduction of more advanced materials. Adding to its durability, the tappet’s body and crankcase are designed to maintain proper alignment, ensuring the roller tappet cannot loosen or turn during engine use.

    OK, great, but we don't really know how great they work, the word "beta" was used, too. That one always scares me.

    Mahlon outlined some methods Teledyne Mattituck uses with sliding tappet system in which oil is squirted onto the cam, and the problem of "dry starts" (engine sits for awhile, then you start it, now you're grinding metal on metal because the oil has drained to the bottom somewhere) is reduced. There was consideration of a 3 year vs. a 2 year warranty (from first engine start) here but the added cost made a 2-year selection with standard tappet technology.

    The only other question was color. Huh? What do I care? It's under the cowling, and I'm parking on the other side of Oshkosh from the show champions section anyway. Burgundy or yellow/black? Well, I just got the maroon seats and seat belts so make it burgundy.

    So here, then, is the description of what I bought for a grand total of $23,855:

    Your standard tappet TMX IO-360 engine will include, propeller governor drive adapter , propeller governor drive gear, propeller governor plumbing and attaching hardware,( however you engine will be setup for fixed pitch use) New Titan Nickel Carbide cylinder assemblies, pressure camshaft lobe and tappet face lubrication, o-ringed thru studs; LSI crank sensor mounting holes, front crankshaft thrust lubrication, relieved cam bearing bores, 1 new Slick magneto, ignition harness and 4 AutoLite spark plugs, single Light Speed Engineering Plasma II Plus ignition system with 4 automotive style sparkplugs and ignition wires, 12V Sky Tec lightweight NL high torque starter, Precision Airmotive Silver Hawk fuel injection system, new fuel pump, inter-cylinder baffles, customizable dipstick tube and dipstick, easy access angled oil filter adapter and oil filter, new dynamically balanced VAR crankshaft, static bay balance to within 2 grams, vacuum pump drive adapter and drive, starter gear support and ring gear, engine logbook and operator’s manual.

    Your TMX engine will be covered by a comprehensive Parts and Labor warranty on the engine and accessories for 2 full years from first start up. It is the owner’s responsibility to maintain the engines preserved status after six months from delivery, if first start up should not occur within the six month initial engine preservation timeframe.

    Your engine will be painted dark grey metallic with burgundy accents.

    We look forward to receipt of your $1,000.00 deposit check.

    As Tim Taylor would say "aarg aarg aarg!"

    Oh, by the way, how am I financing this baby, you ask, knowing that I'm a pay as you go builder? Simple. I'm driving the cars longer. I had calculated when I started the project that if I simply skipped one "car buying" cycle (or two), I could afford to "home equity" the engine purchase and not increase the budget in the house. I rejiggered the home equity line of credit to 4.49% which changes the whole nature of things. Plus, I'm not going to be soaking money into the BBQ at Oshkosh this year, though it would help if you'd click on an ad on this page, I suppose.

    Carolie's final car payment on her Subaru was made two weeks ago and I paid cash for my low-rent Cavalier a couple of years ago and between the two cars, we should be able to go another 4 or 5 years without picking up a new car loan, still be able to put money away for their eventual replacement, and have a paid-for engine very close to the time the plane flies for the first time. This assumes, by the way, that you contribute and become a member of Minnesota Public Radio. Bobby's gotta eat!

    It's due to be delivered in the fall, which should give me plenty of all-winter-long-fun.

    1. Absolutely awesome! Ordering it a day before your birthday seems like a nice way to celebrate, Bob.

    2. Ok, I was doing a pretty good job of controlling my envy for the 30 more horsepower, the fuel injection, the fancy magneto replacement, and the long-term wear preventors like the front crankshaft thrust lubrication, but I lost my battle when I saw this:

      customizable dipstick tube

      I have got to get one of those for my 150 hp, carburetor-equipped slate gray engine.

      Seriously, I had a ride in a 180 hp RV-7A, and it is incredible! You're going to love it.