SARATOGA SPRINGS — The inspection sticker on the Ford Model TT truck reads 1997, the last year that Dottie Madison drove the popcorn wagon on the carnival circuit.

The 1925 vehicle works as good as new more than a decade later, and once again will pump out buttery popcorn for sale at Saratoga Race Course and Cambridge, where it was a famed tradition for decades.

The antique popcorn wagon will make its local public debut Sunday at the Saratoga Automobile Museum,

Madison’s father, Albert Rich, had the rare Cretor-built truck shipped by rail to Cambridge after it was manufactured in Chicago. The Cretor company specialized in building various popcorn and peanut roasting machines.

Rich popped popcorn, roasted peanuts and steamed hot dogs in the truck.

Together, he and his daughter worked the carnival circuit. “They literally were ‘carney’ people,” said Alan Edstrom, director of programs and special events for the auto museum. “She would literally drive this truck back here from Florida.”

Madison later took over the business herself, selling her treats in Cambridge and at Saratoga Race Course.

She finally stopped selling food in 1997 when she was in her 80s.

At age 93, she discussed selling the truck to the auto museum. “She said, ‘What do you say we find a good home for it?’” Edstrom recalled.

But Madison died before the sale was completed, and her heirs decided to seek other bidders.

One of them was Jay Leno, who collects antique vehicles, but eventually pulled out of the bidding process.

Edstrom said Lenno didn’t want to be seen as the rich guy from Los Angeles swooping in to snatch part of the city’s history. Edstrom declined to disclose how much the museum paid for the piece of local history.

After the purchase, the museum tuned up the engine with the help of Don Buesing, a Model T expert who also is proficient at steam engines.

“It was in fantastic shape,” said Bob Ensign, a museum volunteer from Albany who also worked on the engine. “It’s serviceable right now.”

But the truck won’t be driven on public streets because the museum wants to preserve it.

Instead, it will be hauled to various sites this summer on a truck. In the winter, it will be on exhibit at the museum.

Madison’s family members will be at the Sunday dedication, which coincides with the auto museum’s annual Spring Auto Show at Saratoga Performing Arts Center.

Unlike at many antique auto exhibits, the museum welcomes people to touch and climb inside the popcorn wagon.

“Kids are fascinated by it,” Edstrom said.

And adults are, too.

“There are so many people who are in their mid-60s who say, ‘I remember this from Cambridge,’” he said.

The interior is compact. The driver’s seat folds down to make room for moving around when people make popcorn. “It’s almost like a James Bond retro kind of thing,” Edstrom said.

“We’re also showing it off as a marvel of engineering too,” he added.

A steam engine, separate from the truck’s motor, operates the mechanism that stirs the popcorn kernels on propane-heated dishes. The corn then pops onto a metal tray that also is heated with steam power.

Propane will operate the steam engine, although in Madison’s day, she used a mixture of heptane and peptane, Ensign said. That’s too dangerous to use today.

“It was very, very, very volatile,” he said.

The museum didn’t consider repainting the wagon’s exterior, which is a dull gray-black with faded gold filigree designs. Madison used to put varnish over the metal when it got dull, Edstrom said.

“It has such a really great patina, and that’s how people remember it.” The original sign advertising “Fresh buttered popcorn” is still mounted to the side of the wagon.

To sell popcorn on Sunday, the museum had to obtain a health permit from the state so it can legally serve food, said Holly Hulfish, director of exhibits, archives and collections.

But that’s all the wagon will sell.

State regulations for selling meat make it too difficult to hawk hot dogs, she said. Peanuts also are risky, because so many people are allergic to them.

And cigarettes, which were sold out of the wagon in the 1930s, also won’t be found on the wagon.