Breaking News: Engine Upgrade!

The Debonair sweepstakes airplane is going from 225- to 260-hp. That’s a big step up in performance, and there’s a good reason why we’re taking this route.

Those of you who’ve read the Sweepstakes Briefing item in the January 2014 issue of AOPA Pilot , or who saw the AOPA Live This Week video ({A395BD62-A728-4F52-948E-7A1CCDE2C475} know that we borescoped the Debonair’s cylinders and found evidence of pitting and corrosion. Bonanza/Baron/Debonair expert Adrian Eichhorn pronounced the cylinders fit, but we had a nagging feeling. We simply couldn’t give this airplane away unless we corrected the cylinder issue and made sure the entire engine was fit enough to meet the standards of an AOPA sweepstakes airplane.

Pitting as seen through a medical-quality borescope. The cylinder barrel is on te left. The cylinder head is the lighter-colored metal to the right of the junction

Cylinder pitting as seen through a medical-quality borescope. The steel cylinder barrel is on the left. The cylinder head is the lighter-colored metal to the right of the junction

We’d been seeing high iron levels in our oil analyses (the subject of a previous blog post) and after seeing the inside of those cylinder bores we knew exactly where they were coming from: the engine had been sitting for so long that the engine’s steel barrels had been drained of a protective oil coating, and basically rusted. So when I came along and flew the airplane across the nation to have restoration work performed, the corrosion was abraded. Though running the engine for 60-some hours had polished the corrosion and pitting, the bad news was that the iron particles were now in the oil. In short, the engine was “making metal,” and creating a potential danger by contaminating other moving components–like accessory gears, the camshaft lobes, and various bearings.

Eichhorn came up with an amusing metaphor: “Hey, if I’d been laying on the couch for five years, then jumped up and ran to Santa Fe, I’d be having some wear problems of my own.”

To continue flying posed too many uncertainties. Were the camshaft lobes worn, spalled, or scored? Were the pistons’ oil rings about to wear to the point that the engine would begin burning oil? How much longer could the engine go on like this without sacrificing safety?

We had to do the right thing. That meant a top overhaul (new cylinder assemblies, complete with pistons, connecting rods, and associated hardware) at the very least, and a major overhaul at most–if there was any evidence of damage to the “bottom end” (crankcase, crankshaft, camshaft, and their associated bearings and journals).

We debated the options. Among them were doing a top overhaul on the existing engine, or stepping up to a 285-hp IO-520 or 300-hp IO-550 engine. In the end, D’Shannon Aviation proposed another alternative: converting the existing 225-hp IO-470-LCK engine (a -L engine changed–hence the “C”–to a -K variant) into a 260-hp Continental IO-470-N engine of 260-hp. D’Shannon holds the STC for this upgrade, which has proven popular over the years. In fact, there are very few IO-470-K engines out there; most have been replaced by now with more powerful engines–most under D’Shannon STCs.

After some debate, we opted for the -N. We could use the extra 35 horsepower, and we could keep the two-blade McCauley propeller that American Propeller Company had recently overhauled. Besides, we wanted to stay in character as much as we could with the Debonair idea, and going to the -520 and -550 engines would have meant too much power for a complex single that serves so well as a step-up from smaller fixed-gear singles. The 260-hp option seemed the best pathway–and the lightest.

The conversion will be performed by a newly-formed branch of D’Shannon that focuses on engine overhauls and upgrades: Genesis Engines by D’Shannon. With a shop in Mooresville, North Carolina, Genesis Engines is in the heart of NASCAR country. Maybe that’s why it’s called “Race City USA.” Genesis has six technicians with NASCAR engine backgrounds and prides itself on its high quality and extreme attention to detail. John Clegg, director of Genesis operations, puts it this way: “When it comes to balancing pistons, for example, most manufacturers’ overhaul manuals allow two to five grams of difference between pistons. Here, we balance them to within a tenth of a gram. This allows our engines to generate much less vibration, which results in longer engine life.”

After being overhauled By Genesis Engines by D'Shannon, this Continental IO-550 runs on a dynamometer to check power output

After being overhauled By Genesis Engines by D’Shannon, this Continental IO-550 runs on a dynamometer to check power output

Another key partner in the engine upgrade is Engine Components International, or ECi as it’s known. ECi will be providing six new TITAN cylinder assemblies for the upgrade. The cylinder bores will be coated with ECi’s nickel+carbide treatment, which makes them much more durable, longer-lived, corrosion-resistant and reliable than the rusty old cylinders in the original -LCK engine. So so long steel barrels, hello nickel-and-silicon carbide coated ones. ECi has built more than 140,000 TITAN cylinders since 1994 and provides them with a 60-month warranty against premature wear and corrosion.

The TITAN assemblies will come with new valves, valve guides, pistons, connecting rods, wrist pins, and other necessary top end components. ECi will also be reconditioning any bottom end components that may need it, or providing any new such components if those components are worn.

And by the way, ECi’s cylinders come from the factory already balanced to Genesis’ strict tolerances.

Of course, we are well aware of the Notice of Proposed Rulemaking (NPRM) that the FAA is proposing, which would be an Airworthiness Directive affecting certain ECi cylinders made for the Continental IO-520 and -550 engines. The details of the NPRM (by the way, the comment period closed in December 2013) are complex, but it boils down to the FAA wanting some of those 6,000 cylinders taken out of service at 1,000 hours time in service, and some of them removed from service after 25 hours if their time in service is less than 500 hours. The cylinder assemblies not affected by those restrictions would need inspections every 50 hours for their entire lifetimes.

All this because of 30 instances where cylinder head and cylinder barrel junctions failed. Out of 30,000 installed cylinders. And ECi asserts that in none of the 30 cases did a failure cause an accident or injury; typically, there was a loss of 20 percent of engine power–enough to make safe landings.

AOPA feels, and has represented, that the proposed Airworthiness Directive is regulatory overkill, and an unwarranted waste of time and money (The FAA estimates that compliance with the AD would cost almost $83 million).

So by using ECi cylinder assemblies in the Debonair we’re backing up our belief, and have full confidence in the quality of ECi components. Besides, the cylinders being provided for our IO-470-N conversion are not mentioned in the NPRM.

There’s a lot more to this engine upgrade/overhaul than new cylinders, however. I’ll get to the full list of improvements and add-ons in the next post. I just wanted everyone to know that a new engine’s coming, and that it’ll be a huge asset to an already huge project. And if you go to Sun N’ Fun–or several of the regional fly-ins that AOPA is having this year–you can see it for yourself.

  • Terry

    Ahhh, that update was well woth the wait.

  • Mark

    Clearly this will be one sexy, up-to-date aircraft when AOPA is done with it. If I win it the wife may threaten to leave me but it could possible be worth it!

    • David Kenny

      Hey, there are a lot more women than airplanes in this country!

  • tony

    I am so glad you corrected my engine problem. Now can I have my plane. PLEASE

  • tony

    A new engine for my new plane

  • tony

    My plane has all the safety featears a person could ask for. Thanks for the engine. My family will be safe with me now.

  • Barry A Blake

    Thank You! I was concerned about the pitted cylinders for all the reasons you mentioned. Magnets and filters don’t catch all the iron, some will run through the engine.

  • BennytheBrewer

    This is great news! Are there considerations for any electronic ignition e.g. Electro Air? It would seem to be a good time to make the upgrade but I’m not sure if they are approved for 6 cyl yet…. I just checked looks like 6 cyl will have to wait a little longer. Well, if this happens to be my airplane it will be one of the first upgrades I make. I will also be looking for aircraft partners in the Manassas, Leesburg VA area!

  • Josh Dickson

    Why not diesel? Next airplane engine I buy will definitely be a diesel.

    • David Seton

      Why not diesel? – Because there aren’t any.

  • David Stout

    So sorry to read that AOPA has decided to ruin the Debonair. The IO470 K engine is one of the finest engines ever built by Continental. It is a fuel injected 80 Octane engine that is eligible for an auto gas STC. Non ethanol auto fuel in my part of the country is about $2.00 a gal cheaper then avgas. There are 2 Debonairs at our field that have auto fuel STC’s , one of those airplanes has flown over 7000 hrs on auto fuel with an issue! The Deb running auto fuel is extremely efficient has goes a long way to helping hold down the cost of flying. Now this airplane is just another Beech that is very expensive to fly so it probably won’t very much. By the way , I disagree that most IO 470 k engines have been converted to the 260 hp. That is simply not true.

    • Robin

      As an older skylane owner, I definitely agree.

    • Stanley Stewart

      As an owner of a Debonair for 34 years, I can write that the upgrade from a 225 horsepower IO-470-J or K to a 260 horsepower IO-470-N engine is a very significant improvement. The IO-470-N has an 8.6 to 1 compression ratio versus 7.0 to 1, and a larger diameter exhaust system, so is more efficient. I upgraded my 225 horsepower engine to a 260 horsepower IO-470-N after years of burning auto fuel, when fuel without alcohol became essentially unavailable, and the engine was at TBO. I can cruise at the same 150 knots on 2 GPH less (10 GPH) or 10 knots faster at the same 75% power fuel flow (12 GPH, lean of peak). As the Debonair has rubber fuel tanks, any alcohol in the fuel is a strict no no. Apparently there was no fact checking on the statement that most Debonairs have already had engine upgrades. A look at the Debonairs advertised in Trade-A-Plane will show that most have yet to be upgraded, although many have. The same year vee tail Bonanzas have 260 horsepower 260 horsepower IO-470-N engine (1961-63 N35 and P35 models) or 285 horsepower IO-530 engines (1964 and later S35 and V35 models), compared to the Debonair’s 225 horsepower. The Debonair is the same airplane as the vee tail Bonanza with the exception of the empennage configuration. The 300 horsepower IO-550 engine is essentially a longer stroke version of the 285 horsepower IO-520 engine. 285 or 300 horsepower is not too much for a Debonair, but there is significant additional cost to upgrade from an IO-470 series engine to a 285 horsepower IO-520 or 300 horsepower IO-555 engine versus staying with an IO-470 series engine. One interesting thing, a 300 horsepower IO-550 weighs four pounds less than an IO-470 engine!

      • Stanley Stewart

        Typographical error in the above, IO-530 should be IO-520 and sorry about the repeated “260 horsepower” in the text!

  • Dan MacDonald

    How many airplanes are injected (can utilize GAMI injectors to run LOP), and use mogas? Only one: the Debonair with the IO-470-J or -K. Plus they are high performance and complex.

    It was a very poor decision to “upgrade” this engine to a -N. Why would you convert an 80 octane engine approved for mogas to a 100LL-only engine? TEL will soon be banned (the stall tactic of “researching a replacement” over the past 30 years has run its course), no replacement currently exists, and high fuel prices are keeping most GA aircraft in their hangars.

  • Aaron Holton

    Wait, wasn’t the whole point of getting a -K Debonair so it would run Mogas or unleaded aviation fuel?

  • Paul Reed

    I have a K model IO-470 and it is a wonderful engine: now about 1950 hours on a 1500 hr engine. One point, in CA, there is no such thing as non-ethanol auto gas and there is no unleaded avgas, as far as I know. Therefore, those arguments go away for all the Debs in CA.

    The N model engine does a couple of things for a Deb: one, shorter takeoff distances, two, better high density altitude takeoffs, three, slightly better cruise speed. There are several other good things about the N, but I can’t think of them on short notice. If and when I replace my K engine, it will be an N.

  • Dan

    The title of the article was “More Power for (your) Debonair”. Does that constitute a legal contract, because I’d happily accept directions for where to pick it up! You did mean ‘me’, right?!!!

  • Jerry feller

    I wonder if the engine would be replaced if AOPA had to pay for it with their hard earned money. These projects are no more than thinly veiled ads for any manufacturer that donate something.

    • Joanna Smith

      I disagree, the entire point of this is to show current or future airplane owners what’s available on the market! Why? Because we all would love to upgrade if we could so we dream through the sweepstakes with the hope of winning this beautiful aircraft. Also, many don’t know what is involved in upgrading and this provides information on many levels! So I’m very thankful to all the manufacturers who donate something. The least that can be done is to provide credit to the donors.

  • bill

    I don’t care about what engine it has. I will be one happy camper when I win it no matter how much money it cost me to fly. That is what is wrong with some people they care to much about money. Don’t look a gift horse in the mouth.

  • Chris Whitmer

    On paper, this all sounds great, but we all know that no matter how the new owner runs this engine, those cylinders wont make TBO. They will be lucky if they get 800 hours out of them. The machining just isn’t good enough for the cylinders to reach TBO.

  • Crosswind One

    Interesting discussion. As an owner of a ’60 Deb with a J model engine for the last 10 years. Yes, it would be great to have the extra 40HP but at what cost? New engine, baffles, exhaust stack etc. Where does it top out? The 225 model cooks along fine and yes it will run on non-ethanol gas or Mogas. Here in FL non-ethanol fuel is back at about $4.00 per gallon, but it is hard to tell if it is pure and not contaminated. So the difference of and extra $1.50 for 100LL is a no brainer verses the introduction of ethanol into the fuel system. Mogas is also available, but at very few FBos. I believe shopping around for good prices on Avgas is a better alternative than tankering non-ethanol unleaded auto fuel from my local “Shell” station in the back of my car. After all, the Deb has 63 gallons useable. Just a thought.