Title: John Hart (actor)
Content:  John Lewis Hart (December 13, 1917 &ndash; September 20, 2009), also credited as John Hilton, was an American film and television actor. In his early career, Hart appeared mostly in westerns. Although Hart played mostly minor roles in some fairly well known films, he was probably best known for having replaced Clayton Moore in the television series The Lone Ranger for one season (1952–53).
Title: John Hart (actor)
Content:  Jack Armstrong (1947) film serial. Hart did stunt work and acted in numerous westerns. Hart was eventually offered the opportunity to replace Clayton Moore on The Lone Ranger television series. Based on the assumption that the masked character, rather than the actor, was the true star of The Lone Ranger, the program's producers fired Moore (presumably over salary differences) and replaced him with Hart, who was of a similar build and had a comparable background in Westerns. However, the public never truly accepted Hart as the Lone Ranger, and by 1954 the producers returned Moore to the role. According to 
Title: John Hart (actor)
Content:  as Tonto, spoofing their characters. Hart's last theatrical film appearance was in 1981's The Legend of the Lone Ranger in which he appeared as a newspaper editor. He appeared in the television series Happy Days as the Lone Ranger in the episode "Hi Yo, Fonzie Away" (February 9, 1982). In this episode Fonzie, played by Henry Winkler gets to meet his childhood hero, the Lone Ranger, for his birthday. Hart's other major late appearance was in an episode of The Greatest American Hero, My Heroes Have Always Been Cowboys, where Hart gives the title character an inspiring speech about heroism.
Title: List of The Lone Ranger episodes
Content:  (John Hart takes over the role of the Lone Ranger.)
Title: John Hart (actor)
Content:  ; 1972: The Roommates - Sam - Sheriff ; 1973: Santee - Cobbles ; 1973: Blackenstein - Dr. Stein ; 1974: Welcome to Arrow Beach - Doctor ; 1974: The Centerfold Girls - Sheriff (segment "The First Story") ; 1975: Gemini Affair - Bob ; 1976: Blood Voyage - Jules ; 1977: John Hus Theologian ; 1978: Invisible Strangler - Harbormaster ; 1978: Cheerleaders Beach Party - Mr. Langley ; 1981: The Greatest American Hero (TV Series) - Lone Ranger ; 1981: The Legend of the Lone Ranger - Lucas Striker ; 1982: Happy Days (TV Series) - Lone Ranger (final appearance) 
Title: John Hart (actor)
Content:  Moore's autobiography I Was That Masked Man, Moore never knew why he was replaced by Hart, and also stated that he had not sought a pay increase. Hart acted in minor roles in two episodes of The Lone Ranger before being asked to replace Clayton Moore for the entire third season. The episodes were "Rifles and Renegades" (#34) and "Sheriff at Gunstock" (#46). Hart continued to act in films for more than two decades, appearing in films of several genres, almost always in supporting roles. Hart appeared twice in on the TV series I Love Lucy as Lucy's old boyfriend 
Title: John Hart (actor)
Content:  - U.S. Marshal Matt Furness ; 1952: Dead Man's Trail - Ranger Captain (uncredited) ; 1952: Caribbean - Stuart ; 1952: The Golden Hawk - Pirate Helmsman (uncredited) ; 1952: The Pathfinder - British Sergeant ; 1953: ''The Lone Ranger (TV Series Season 3) - The Lone Ranger ; 1953: Prince of Pirates - Captain of the Guards (uncredited) ; 1953: The Great Adventures of Captain Kidd (Serial) - Jenkins [Chs.4-6, 8-10] ; 1953-1955: I Love Lucy (TV Series) - Jim Stevens / Lifeguard / Tom Henderson ; 1954: Gunfighters of the Northwest (Serial) - Sgt. Dan Wells (uncredited) ; 1955: Dial 
Title: John Hart (actor)
Content:  in Canada and featured some Indians in a favorable image. Interviewed by Tom Weaver in "Western Clippings" magazine (May–June 2000), Hart revealed that he met actress Beryl Braithwaite when she played a role in an episode of the series; they married just days later, with "Hawkeye" co-star Lon Chaney, Jr., the best man at the wedding. In 1965 Hart made two brief appearances on the TV series Perry Mason, including the role of title character and murder victim Jamison Selff in "The Case of the Wrathful Wraith." In the 1970 film The Phynx, Hart played the Lone Ranger alongside Jay 
Title: The Lone Ranger (TV series)
Content:  to play the role of the Lone Ranger. Once again, the 52 new episodes were aired in sequence followed by 52 weeks rerunning them. Despite expectations that the mask would make the switch workable, Hart was not accepted in the role, and his episodes were not seen again until the 1980s. At the end of the fifth year of the television series, Trendle sold the Lone Ranger rights to Jack Wrather, who bought them on August 3, 1954. Wrather immediately rehired Clayton Moore to play the Lone Ranger, and another 52 episodes were produced. Once again, they were broadcast as a full 
Title: The Lone Ranger (2003 film)
Content:  This version takes a look at the character in the years before he became a legend. It all begins with the introduction of Luke Hartman, a 20-year-old Boston law student who witnesses the murder of his brother, a Texas Ranger. He himself is wounded in the midst of the chaos, but is rescued by the Apache Tonto, and subsequently becomes smitten with Tonto's sister Alope. He then devotes his life to avenging the death of his brother and fighting injustice, and in the process becoming a worldwide legend.

Question: when did john hart play the lone ranger?
Answer: from 1952 until 1953.