TBO Advisor
JULY-AUGUST 1996
A
by Wayne Thomas
Reproduced by permission.
Let's assume for a weird moment that you've never heard of Visalia, California's Ly-Con Aircraft Engines before. And, maybe you really haven't, but I'll bet that you have heard of airshow performer of the year, Sean Tucker. Or 1993 and 1995 Reno Air Race top-finisher Patty Johnson, or John Harmon, designer of the record-setting Harmon Rocket. What do the aforementioned people and machines have in common? Answer: Ly-Con Aircraft Engines.
Ly-Con either builds engines for, or supplies high-performance components to an extensive (and growing) list of world-class pilots and their crews. At the same time, although they do turn out a good number of hot-rodded engines for Experimental use. They're also a full-on TCM distributor and have been an FAA certified repair station since March 1981, so they handle the full range of standard category (type-certificated-engine; Spam-can airframe) overhauls, as well. What is Ly-Con's specialty? Perhaps the best answer to that question would be diversity. No matter if you're looking for a reasonably priced overhaul of the weary A-65 in your J-3, a major of the Lycoming VO-435-BlA in your Bell helicopter, or if you've got the need (and the budget) for an engine to make your Pitts Special hang on its prop like a helicopter (a la Sean Tucker), the friendly folks at Ly-Con can fix you right up. Want a factory re-man Continental or Lycoming engine? Come on down, they've got you covered there, too. Ly-Con's shop foreman, Steve Mehalek, turned wrenches for race-car pilot Roger Mears prior to joining Ly-Con back in 1989 and finds his race car engine sagacity alive and well today at Ly-Con. Steve makes a good point when he explains that Ly-Con's considerable experience of putting together high-output Experimental type engines lends unseen benefits to the work they do on Certified engines, as well. He says, "with all this Experimental stuff we do, we try to push them a little to see how far we can make them go. This is going to tell us a little bit more, down the road, how we can make an even better stock engine. All our hot-rod effort falls right back on our standard category work."
Good News Travels Fast
If you're one of the people who have heard of Ly-Con before, its most likely because you have either had an engine overhauled by them or you know somebody who has. Ly-Con does no advertising. From their humble beginnings some sixteen years ago, they have built a business that today does a respectable 250 to 300 engines per year (for clients all over the world) based entirely on word-of-mouth referrals of satisfied customers. Ken Tunnell, Ly-Con's founder and president, tells me that he prefers a low-key approach to earning new customers (and in keeping them). "We don't blow a lot of smoke or make sales pitches," Ken says, "we don't advertise powder-coating of engine parts. People we deal with all the time and who know us, they just drive in and give it [their tired engine] to us." Modesty, like honesty, is an excellent policy and it appears to work well for Ly-Con. At the time of my visit (in late April 1996), they had, get this, roughly one hundred jobs waiting to get in the shop and more than 300 open work orders in process. And the phone was nearly ringing off the wall (actually, it was off the wall and stuck to the left side of Ken's face much of the day).
Who Are Those People?
I asked Ly-Con shop foreman Steve Mehalek who he considered their typical customer to be. Normally this is not considered to be a trick question, but with the vast array of work taking place at Ly-Con, this innocent query quickly brought on a wave of silence. The scene began to take on a certain O.J. deposition quality as the room went quiet while we all sat on opposing sides of a huge brown desk, my tape recorder parked right in the center. Mehalek finally spoke. "We do so many different types of jobs, its hard to say," he lamented, "The one thing they all seem to have in common is that they al] want a good job at a fair price. We try to work with our customers on all aspects of repairs." Each job at Ly-Con is approached, quoted, and handled on very much a singular basis. Which is not surprising, again, given the panoply of work they undertake. There's no "standard" price list, nor are there many instances where internal policy dictates use of new-only components (beyond what's called out in Lycoming S.B. 240L or TCM S.B. M87-11, Rev. 2). Sure, Ly-Con has processes and parts they prefer to use but as Ken puts it, they do "mostly what the customer wants." By taking the time to understand each customer's needs, wants, budgetary restraints, and his/her expectations of the engine after overhaul, and with few set policies to dictate what components or processes they can or cannot offer, Ken says Ly-Con is able to deliver what they feel is the best product possible for each customer. Not a one-size-fits-all engine. Take camshafts, for example. I can think of at least half a dozen overhaulers who enforce a strict "new-only" policy when it comes to camshafts. When you call Ly-Con for a quote, however, get ready to be presented with several bump-stick options which may include: new TCM or Lycoming cam; PMA cam (Superior or Air Support); or a custom re-grind. "PMA cams, regrinds, we’ve used them all," Ken points out. "It may be a toss-up, the amount of new versus reground cams that have problems, but it's not a big problem with us. A lot of times, the new ones will be out of whack and the regrinds will actually be within a tighter tolerance than the new ones." Oh, really? I thought to myself. By this point I'm wondering how Ken and his cohorts could know so much about the cams that come through their shop. And what is it that gives them such obvious confidence to offer reground cams to their customers, when some overhaulers treat reground cams as though they all come in tightly-wrapped.
The Doctor Is In
The answer to this question (and to literally dozens of other questions) comes from a device known as The Cam Doctor, made by Quadrant Scientific of Louisville, Colorado. The Cam Doctor is a very precise measuring instrument that surveys all camshaft dimensions for example, lift, duration, overlap, ramp acceleration, taper, and individual lobe timing tolerance. In operation, the Cam Doctor is a simple-looking affair: You lay a cam on some V-blocks, bring the position-feeler down onto the cam's base circle, and spin the cam by hand. The unit's output is directed to a nearby desktop computer. The captured dimensional data (accurate to ten or twenty millionths of an inch) is instantly plotted on the PC's screen. At the same time, the cam's design data (the theoretical contour, the blueprint data) is also drawn on screen, overlaid, you might say, on top of the real-world cam data. In this fashion, the Cam Doctor compares actual cam data against the intended design parameters for the cam being tested. Dissimilarities are immediately apparent to the untrained eye and result in instant rejection of the cam by Ly-Con. The Cam Doctor, as essential an item as it seems to be, is also a remarkably rare one to find in an overhaul facility. Aside from the one at Ly-Con and the one that Teledyne Continental owns, Steve believes there to be only one or two others in use in the aircraft industry. [The only other two I've seen are at RAM Aircraft in Waco, TX and Aircraft Specialties in Tulsa. OK.] That's a grand total of four such units, industry wide. Here's the clincher (and an example of Ly-Con's fanatical nature): Every cam they intend to use in a customer's engine gets a check-up on the Cam Doctor. That's every lobe, of every cam. (I wonder if TCM checks every lobe of every cam that goes out the door?) No matter if the cam is factory-new, PMA, or a regrind it gets lobe-verified for correctness. A hard copy of each cam's computer-generated wellness report is kept on file at Ly-Con (a copy is provided to customer upon request); there is never any doubt as to the cam's dimensions. Steve Mehalek notes that prior to having the Cam Doctor, "we used to just buy parts, give them a visual inspection (as most good shops will do if at least to check if the part has been dropped on a concrete floor somewhere), then install them. Some motors would run good, some not so good." He says the Cam Doctor has put an end to this by allowing easy detection of mis-machined cams and/or cams that have been improperly part number labeled. "We've rejected a few," Steve confirms. As a result, there have been no new outbreaks of the dreaded "Mad Cam" disease within the city limits of Visalia, California for as long as anyone can remember. Lifters are a somewhat different story at Ly-Con. Not unlike what is pretty much an industry-standard approach, Ly-Con will use either new or reground lifters in most Lycoming engines (at the option of the customer), whereas in Continental engines they use only new lifters. No reground Continental lifters are used. Regrinding of cams, lifters and crankshafts, and most engine case work, is outsourced to many of the top, FAA repair stations that specialize in the type of rework required. Nickson's machine shop (in Santa Maria, CA) does about 90% of Ly-Con's crankcase work, while crankshafts are sent to either Nickson's or AEA for re-grinding. Polishing and balancing of crankshafts is done in-house on Ly-Con's Stuart-Warner balancer. Connecting rods are overhauled at both ends. Big-ends are bushed and align-bored, then the rods are balanced end-to-end. Pistons are weighed and matched with rings and wrist pins in place. Other tasks performed in-house are the repair of most accessories; carburetors, alternators, magnetos, and beginning the day after my visit, fuel injection.
Cylinder Options
New cylinders are offered as an option, and as you may have expected by now, you'll likely discuss many other options as well when calling Ly-Con for an overhaul quote. In helping you decide, and depending on what type of engine you have, Ken will ask various questions before making his suggestion to you. "Nitrided or plain steel are what we like the best," Ken tells me, without hesitation. His experience with Cermicrome has produced somewhat varied results. "We've had really good luck with it in Continental engines, especially the lower horsepower engines. A little more problem with engines that make temperature, and a lot more problems with Lycomings that make temperature and high compression. They [meaning Cermicrome cylinders] don't like temperature at all. You run a high head temp, like 450 degrees or better, and the chrome will go right out of it." Ken's sixteen years of experience will help you make a beeline toward The Right Choice for your engine. To underscore his point about thermal loading taking a toll on chrome-plated cylinders and top-end components in general, Ken says that Ly-Con now has a policy whereby they recommend all engines be run no leaner than 150 degrees on the rich side of peak. Ly-Con sets up engines to burn more fuel and they educate their customers to do the same. Ken feels strongly that the old standard of leaning to 50 degrees rich of peak no longer provides a large enough margin of protection. When I asked why he felt so strongly about this, Ken told me that, in his opinion, today's avgas is just not as good as it was fifteen years ago. "Of the fuel samples I've had analyzed over the past four or five years, I have noticed high levels of toluene [methylbenzene, an aromatic fuel-octane enhancer]. The samples from western supplies contain anywhere from 28% to 36% toluene, whereas the samples from eastern supplies contain more like 7% to 14% toluene. Years ago, we used to see only about 7% to 10% toluene in our local [western] fuel supplies." Although he admits not knowing the exact cause, Ken told me he suspects the high toluene content of today's aviation fuels may have a lot to do with the increasing number of temperature related failures and rapid wear rate of valve stems, guides and cylinders seen by Ly-Con in recent years. "Run more gas through it, keep the engine cooler" is Ken's staunch recommendation in all cases.
Ly-Con has abundant experience with nearly every imaginable repair process in piston aviation. One of the few they've not explored deeply is CermiNil. "We've gotten spoiled on the Cermicrome, so we really haven't ventured into CermiNil. We just kind of settled into the steel nitride. It is something that holds up well and gives us good service, and we can trust it, so that's what why we’ve been using it a lot," says Ken. I was also told that when they do have cylinders chromed, these days they most often use channel-chrome. Regardless of barrel type, Ken recommends Phillips 20W-50 mineral oil for break-in.
Dyno Run-In
After assembly is completed, every engine get wheeled into the dyno room for a series of tests and performance evaluations. Once attached to the dynamometer with all test probes connected and a fixed-pitch propeller bolted in place, every engine undergoes a minimum 1.5 hour test run. From the control room, a battery of engine performance parameters are analyzed, displayed, and recorded by a computer system. An hour and a half is the minimum amount of run-time each overhauled engine spends getting checked out. Only when the gathered data indicates that the engine has met or exceeded Ly-Con's standards does the engine get signed off for release to its owner. A hard copy of the performance data is kept in archive at Ly-Con. (A copy will be provided to the customer upon request.)
After the Sale
One of the most important things to consider when determining which shop is going be blessed with your overhaul dollars, without a doubt, is the warranty offered on the labor and materials they provide. Ly-Con warrants its workmanship on normal-category (non-Experimental) engines for one year or 300 hours, prorated to TBO at thirty hours per month. The current "industry standard" by contrast is six months full coverage and pro-rata to TBO at 40 hours / month, which falls somewhat short of Ly-Con's standard. For the average owner, it means the difference between a four-year pro-rata period (with someone else) and a five-and-a-half-year pro-rata period with Ly-Con. Looked at another way: You could expect 50%, warranty coverage if a problem happened 33 months into your next TBO run (that's almost three years after the overhaul) with a Ly-Con engine. With a "competitive" overhaul, you might be looking at only 33%, reimbursement for warranty work at the same 33-month breakdown period. (A typical warranty gives you 50%-or-better coverage until only the 20th month less than two years after taking delivery of the overhauled engine.) This gives Ly-Con's workmanship coverage a well defined edge over much of the industry. As for the warranty coverage on parts, Ken tells me they are having to re-work some things, "We're going to have to change some of our warranties on parts because the OEMs are changing theirs. So we'll have to let the manufacturer cover the new parts we buy." In other words, your warranty on parts is actually that which the manufacturer offers. If this sounds a little ugly, don't despair. Ken definitely does not like to get stuck in the middle of warranty hassles and, least of all, does not want any customer of his to get left holding the empty milk carton. We like to stand behind our stuff real well and we expect whoever we buy a part from to stand behind it just as good as we do. If they're not going to stand behind their stuff, there's no reason for us to sell it," Ken says, obviously referring (obliquely) to such after market parts makers as Superior and AirTech.
Ly-Con's warranty of Experimental engines is the same as for a Certified engine, except the time tables are cut by one half. Accessories, in either case, are warranted for one year or 1,000 hours. (Again, that's substantially better than average. Infinitely better than no accessory coverage, which is what you sometimes run into.) One more neat feature about Ly-Con is Rory Baily. He is their resident warranty-claim, vendor/customer liaison. If you encounter a need to file a warranty claim with a vendor (TCM, Superior, etc.), Rory will be there, ready to lay down his pen for you and get things handled. What if a crack develops in a head or crankcase after 100 hours?" I asked. Ken says they normally do not charge the customer for repairs when this type of thing happens. "We usually look and try to figure it out [the cause]. If the guy's just abusing the thing then we'll talk to him, but we will normally pro-rate it in that case. We'll give him a big lecture, or whatever, then we'll fix it." (Hey, sure beats no lecture and no consideration, right?) Weld repair of cylinder heads is generally accepted at Ly-Con but as with most other aspects of their operation, each situation is evaluated individually. For example, if the area to be repaired has more than one crack or is located where they feel it will likely recur, then the part (along with the notion to weld-repair it) is discarded. As for oil usage: An oil consumption rate of less than six hours per quart is considered by Ly-Con to be grounds for a warranty claim. They won't tell you to "keep flying it" until you're up to a quart every two or three hours, then tell you to go back on mineral oil and run the engine balls-out "for awhile," etc. As Ken says, "A quart in six hours is marginal on a new engine. If we put nitrided or new cylinders on, they're normally good for a quart in fifteen to thirty hours. We're doing a set right now for a customer," he continues. "They were a quart in five hours or so, so we replaced them." The No-Charge Check-Up With every overhaul that Ly-Con does comes a free inspection when you log your 25th hour on that fresh engine. This a great feature and is surprisingly comprehensive. The list includes:
  • An oil and filter change. They will cut open your oil filter and inspect for excessive metal production.
  • An oil analysis is ordered.
  • A thorough borescope examination is performed on each cylinder. All cylinder compressions are checked and readings noted.
  • The engine's baffling is examined for condition and proper placement.
  • The exhaust manifolds are checked for signs of leakage and proper placement (and presence) of heat shields.
  • All major fasteners under the cowling are verified for proper tightness. (Cylinder base nuts have a way of relaxing within the first 50 hours on anyone's engine. This is definitely worth checking.)
    • Again, all done at no added cost to the airplane owner. After the 25-hour check, you will be briefed on the findings. Also at this time they will provide suggestions as to areas of your engine operating technique they feel should be refined to maintain engine health. Wait a minute. Go back over that previous paragraph again. Bingo! What a concept! Do the whole shebang for free and find out early-on: Is anything shredding apart? Can you read part numbers on the metal pieces inside the oil filter? Is the owner over-leaning? Is the baffling installed correctly and able to properly control the environment inside the engine compartment? Is part of the exhaust system about to melt anything or contribute to an engine cooling problem (or a fire)? And, is the engine still firmly bolted to the rest of the airplane? If any person involved in the overhaul business ever wanted to reduce his or her risk of potential comebacks, warranty claims, irritated customers, FAA probes, litigation or sleepless nights this, it would seem, is an excellent way to go about it. Ken and Steve can tell a lot about how the engine is being treated, for example, by doing a borescope inspection. If it appears that the engine is being run too lean (or too rich, for that matter), it is probably not too late to take corrective action now and prevent a major warranty claim pay-out down the road. For the same reason, Ken is real stickler on making sure the baffling is up to the task it is designed for. The same thing goes for the cutting open of oil filters and doing an oil analysis. Problems are always bigger down the road.
    Ly-Con Today: Busier Than Ever
    With all this work, general tinkering, and R&D going on at Ly-Con, one might reasonably expect the company to occupy a vast facility with an under-roof square footage number well into five figures. Believe it or not, Ly-Con and the nineteen people they employ make it all happen in a mere 4,000 square feet of shop area. Talk about a compression ratio! Their capita-per-square-foot ratio rivals that of a Manhattan commuter train at 5:00 p.m. on a Friday. It's one of the most elbow-rich work environments we've seen. To the rear of the main building stands a roughly 5,000-square-foot building that is currently used for storage of incoming work, TCM spares, and Ken's personal supply of new Super Cub parts. (I have no idea what he plans on doing with these.) I lost count but there were literally dozens upon dozens of large bins containing engines which had been torn down, cleaned, inspected, and now await reentry into the main shop for completion. All types of engines are in here, from helicopter engines to you-name-it. Well, almost all types. Ly-Con hasn't done a radial engine overhaul] for about thirteen years now. That's about the only type they choose to no longer service. Ly-Con has maintained a steady rate of growth throughout its 16-year existence. "Business for us has doubled in the last year and a half," Ken tells me with a certain exhaustion in his voice. He also points out an interesting phenomenon that occurred when the Chevron incident hit. He says that, like many shops in the western U.S., they experienced a flood of new business once the affected engines were identified and Chevron began footing the bill for repairs. They worked on a total of somewhere between 80 and 100 of these "Chevron" engines during the peak months of the episode. But even though the "detonation" engines have all come and gone, business volume has not dropped back down. Even so, all things considered, the wait for a major overhaul is not all that long. Ken tells me that the turn-around time for a standard, Certified (no-Experimental) type major overhaul is currently running about four to eight weeks. Special requests such as a full-blown hot-rod major of an Experimental engine takes a little longer, anywhere from 90 to 120 days, depending on what your needs are.
    Though the majority of Ly-Con's work arrives by truck, they also perform complete removal and installation of overhaul cores when customers need it. Ken's brother, Darrell Tunnell, operates his own FBO at Visalia Municipal Airport, about a mile from Ly-Con, which is where Ly-Con performs the engine R&I work for their customers who fly in.
    Expansion
    As mentioned earlier, the ratio of elbows to Florsheims is currently something of an embarrassment for Ly-Con. Happily, the cure for Ly-Con's growing pains is located right next door to their current facility. At the moment, this cure is in the form of a vacant 2.04-acre lot recently purchased by Ly-Con. Ken says they'll have a shiny new 15,000-square-foot facility up and running on that lot by this time next year. (At the rate they're going, I can see them having out-grown this new place just about the time the Edison man makes that first spark upon connecting the juice to it.) A number of Ken's immediate family members are involved at Ly-Con. His father, Lloyd, and brother, Bryan, work the shop. Ken's mother, Kathy, and his wife Darla handle some of the bookkeeping (mostly TCM warranty claims, Ken tells me). Ken's other brother, Darrell, has gone his own way and operates his own FBO, as mentioned. Like the rest of the Tunnell family whom I had the pleasure to meet, Darrell is a very talented and easy-to-get-along with person. I visited his hangar late in the day to witness the borescope examination Steve was performing on a Cessna 180, as part of Ly-Con's free 25-hour follow-up inspection. While at Darrell's hangar, I couldn't help but notice the impressive variety of work he, too, had going on. Aside from maintenance of piston engine aircraft, Darrell is also factory trained by Rockwell for turbine engine repairs. (Sorry, but the span between adjoining hangars will probably not allow you to roll that DC-10 of yours into Darrell's place for that quick oil-change you've been putting off.)
    To Sum It All Up
    If you ever find yourself in the market for a quality, sensibly-priced major overhaul (or you want to fully trick-out the fire breather for your home built), and yet you have a craving for a vast array of part and process options to choose from, then you should give Ken Tunnell or Steve Mehalek at Ly-Con a ring. Ken and Steve, it turns out, have the same middle name: Flexibility.
    Bus: 559/651-1070 Fax: 559/651-3212 Email: lycon@lycon.com