TICA, N.Y. — David Monte Verde hears it still. Even now, even here — in a restaurant near the rail yard, above the din of an all-you-can- eat lasagna night. It rumbles through his memory the way it thundered through the Genesee Valley of his childhood, bound for Buffalo, making time. The Phoebe Snow.

"When that train came down the hill, the sound of it would just echo across the valley," he says, staring past the restaurant's gaudy glare. "You could set your clock to it."

And when she pulled into the Dansville station each afternoon at 5:27 — her brakes sighing, her gray, yellow and maroon finish gleaming — young David's universe was in its rightful order. Mom and Dad were alive, supper was waiting, and the pride of the Lackawanna line would be back again tomorrow, looking to make time.

It has been about 40 years since the original Phoebe Snow made its last run, and nearly that long since Mr. Monte Verde watched the last passenger train fade from the station platform of his small town in western New York. He was 16, old enough to know that crews would soon be tearing up the Lackawanna rails from the surrounding hills. All he could do was cry.

Trains have defined him ever since. "You get them in your blood," he says.

Today, Mr. Monte Verde is the president of his own railroad, a profession so uncommon, so linked to another time, that it conjures images of pocket watches and top hats. Strangers often misunderstand him to mean that he somehow earns a living by overseeing a fleet of model railroads. No, he has to explain: I own the real thing.

His is a short-line railroad called the Genesee Valley Transportation Company, which at last count had 27 locomotives, hundreds of boxcars and control of nearly 300 miles of track in New York and Pennsylvania. When a major hauler chugs into the grimy Utica yard with raw copper from Texas, a G.V.T. engine takes over, pulling the loaded cars down 13 miles of track and into the red-brick maw of the Revere Copper Products plant in Rome.

Mr. Monte Verde, 55, carries his solid build with the frenetic air of a commuter waiting for a train running late. He made the not-so-seamless transition from rail fan to rail businessman by collecting anything that reminded him of those childhood days: trainmen's keys, passenger- train china, photographs, cabooses — and then, well, locomotives. "It kind of got away from me," he says.

He has learned that the business of railroading spares little time for sentiment; there are customers to woo, government grants to win, connections to make. It is also a sobering barometer of the fragile upstate New York economy. When two paper mills shut down in the Adirondacks last winter, Mr. Monte Verde and his four partners lost nearly a third of their business. They were forced to lay off more than a dozen trainmen in a process he likened to "losing part of the family."

The comment reveals the blurred distinctions in Mr. Monte Verde's life, between work and leisure, rail yard and home, past and present.

He often lapses into the language of an alternate universe: of wide cabs, Alcos and "moving meets" (the point at which two trains traveling in opposite directions pass each other). He says, "Being a railroader takes over your life." One of his most vivid memories as a parent is the time, nearly 20 years ago, when he changed the diapers of his oldest son, Charlie, in a Buffalo rail yard.

"It was his first rail fan trip," the proud father says.

In 1980, there were 220 short-line railroads in the United States; today, there are 550, thanks in part to the lifting of some government regulations that encouraged larger companies to sell off their little-used and abandoned branch lines. Those in the railroad industry say the arrangement has generally worked out well, with the major rail companies teaming up with the short-line operations to haul goods and material.

Even so, railroading has its familial tensions. Many rail fans blame the businesses for mismanaging and ultimately killing dozens of passenger and freight trains that once inched across the nation's belly with proud and poetic names. (Once there was the Atchison, Topeka and Santa Fe; now there is Amtrak.) But many rail businesses regard the fans as nostalgia-addled fanatics who expect them to run empty passenger trains at a financial loss, simply to conjure nice memories and provide the occasional photographic moment.

Mark Hemphill, the editor of Trains magazine, says the discontinuation of many passenger trains in the 1950's and 60's spurred a mutual distrust that manifests itself today in odd ways. Conspiracy theories abound. Some rail companies even delicately ask whether a job applicant is, how shall we put this, a rail enthusiast, forcing some to become what are called "closet rail fans."

"The feeling has been that the rail fan will run trains for the sake of running trains, whether or not they make money," Mr. Hemphill says. But he adds that the idea that an enthusiast cannot be prudent in the business of railroading is "silly."

There are, after all, the likes of Mr. Monte Verde — his company's logo on his shirt, a worn trainman's switch key in his pocket. The inside of his well-traveled Dodge sedan crackles with the short-wave conversations between dispatchers and train engineers. Whenever he sees an Amtrak train whiz past, he reaches for the schedule he keeps tucked in the car's sun visor, just to see how late it is running.

But that cluttered Dodge is a satellite office of his company's headquarters in Batavia, about 23 miles east of Buffalo. He roams the state and eastern Pennsylvania, meeting with clients, buttering up politicians, and doing anything else he can to keep his company profitable.

After graduating from college, Mr. Monte Verde spent two decades in the business of rail equipment and signal supplies, then worked for a few years at Kodak in Rochester. All the while, he fed his rail passion, studying railroad history and taking train photographs by the score.

In 1987, he and four partners bought and restored an Alco engine, made money by leasing it out, and then donated it to the Rochester chapter of the National Railway Historical Society. "Then we bought two more," he says.

Today, the partnership that became Genesee Valley Transportation oversees five active rail lines. They include the Depew, Lancaster & Western Railroad, featuring a seven-mile run in Batavia that moves loads of fertilizer and beer; the Delaware-Lackawanna Railroad, which hauls grain and propane 30 miles from Scranton, Pa., to the Poconos; and the Mohawk, Adirondack & Northern Railroad, here in Utica.

The morning after his lasagna feast, Mr. Monte Verde walks through the gravel and grime of the Utica rail yard, pausing to examine a 1964 Alco engine nicknamed Jumbo. A rail fan, he says, marvels at the paint scheme of the engine, imagines photographing it against a setting gumdrop sun. But an owner studies the wear and tear on the steel wheels, and wonders whether it is time for old Jumbo to take a trip to the repair shop.

Soon the 132-ton Jumbo is chugging through the rail yard landscape of wheat-colored cattails and 20-foot piles of logs, "switching and kicking" rail cars into position along several tracks. Some contain junk destined for a steel mill; others carry copper for the Revere plant in Rome.

The engineer, Bob Hoffman, stout and 51, lives outside Rochester but spends four nights a week in a converted rail car he keeps in the yard. He adjusts the throttle and peers into his side-view mirror, occasionally pausing to bite a glazed doughnut and slurp some cold coffee.

His lanky assistant, Jeff Collins, 40, used to work on a rail line that served a paper mill, not far from his home in Watertown. But that mill closed, and now he spends weeknights on a cot in Utica. Part of his job is to hop off the engine every now and then to set the switches and rattle off the identification letters and numbers of the cars over a two- way radio.

"Fire away there, Jeff," the engineer says, clipboard and pen in hand.

"HWA 12778, HWA 882202."

Mr. Monte Verde rides with them for a while in the battleship-gray engine cab; with voices raised above Jumbo's heaves and sighs, he and the men talk trains. About the guy who lost a leg a week earlier in a Syracuse yard. About that remote station sign, just above Boonville, which simply says "Hell." About the exact meaning of that milepost in the yard ("It means we're 235 miles from Grand Central Terminal," Mr. Monte Verde says).

The agile Mr. Collins leaves the cab and pulls the pin that connects Jumbo to its load. The four rail cars roll away, as if in a dream, onto a sidetrack, where they will be hitched up and pulled on another day.

"That's a perfect kick," Mr. Monte Verde says, in the language of his universe. Recently, he experienced a different kind of perfect kick. After years of scouring rail magazines, memorabilia conventions and the Internet for anything related to the passenger trains of his Dansville childhood, Mr. Monte Verde came upon a photograph that had been posted on a rail fan Web site. A rail buff, riding in the back of the last Hoboken, N.J.-bound passenger train on the Lackawanna line, snapped the photo as the train pulled from the Dansville station on a hot July day in 1962.

There, in black and white, is the clapboard building, the platform, the shingle bearing the name of the town. And there, near the baggage cart, is 16-year-old David Monte Verde, hands on hips and tears to come.