"F.I.S.T." is a punchless attempt at heavyweight movie melodrama. Ambitious but ultimately banal and inconclusive, the picture exhausts well over two hours in a methodical uphill struggle to derive hard-hitting social significance from a tedious, superficial chronicle of the rise and corruption of a labor leader.

Named Johnny Kovak and portrayed by Sylvester Stallone, in his first role since "Rocky," the protagonist is supposed to compromise his creative efforts on behalf of a national teamster's union, the Federation of Inner-State Truckers, by sealing a Faustian pact with gangsters in exchange for muscle during a violent strike.

"F.I.S.T." might be described as a Big Rig That Couldn't. Grinding heavy expository gears, it tries to cover more than 20 years in Kovak's public and private lives and does justice to neither. The filmmakers keep straining for what they may have envisioned as Academy Award heights, but their vehicle conks out well short of the summit.

"Rocky" built its Oscar-winning success on Stallone's cagy reworking of elements from at least two earlier Oscar winners. "On the Waterfront" and "Marty." The screenplay for "F.I.S.T.," commissioned by producer Gene Corman from former Rolling Stone reporter Joe Eszterhas, a lasting culture hero with many of us for his sarcastic coverage of Evel Knievel's Snake River debacle, seems to be haunted by at least four earlier Oscar winners: "All the King's Men," "On the Waterfront" and both parts of "The Godfather."

It's unlikely that "F.I.S.T." will also be remembered as an inspired reworking of successful influences. Although the influences are obvious, they stick out like a fistful of sore thumbs, presumably injured in misguided acts of imitation. The dark-toned color photography (supervised by Lazlo Kovacs) is very much influenced by "The Godfather," but it doesn't harmonize with an ominous dramatic vision as the photography of "The Godfather" did. "F.I.S.T." lacks that enveloping, voluptuous sense of menace and corruption. Structurally and stylistically, it's close to the dated, overexplicit model of "All the King's Men," which doggedly oversimplified the story of a political leader's rise and fall.

"F.I.S.T." is certainly one busy scene (and meticulously appointed setting) after another, but the scenes don't add up to a story that expresses a pertinent viewpoint about the labor movement or leaves a measurable dramatic impact. Many scenes are not particularly effective on their own terms. For example, Norman Jewison's direction of the clashes between strikers and hired police left me wondering if he had directed one musical too many. These confrontations, marked by such oafish "rhythmic" punctuation as a composition of the cops smacking their nightsticks in unison, resemble overproduced production numbers, like the ones in Jewison's heavily labored movie version of "Jesus Christ Superstar."

What's worse, Jewison can't seem to conceal the fact that he's a little short of extras. There aren't enough members of his labor violence chorus to fill up the screen. Busby Berkeley's "Lullaby of Broadway" number in "Gold Diggers of 1935" actually expressed more menace and terror, not to mention more period authenticity. The thought of being overtaken by those dancing feet is more alarming than the thought of being caught between Jewison's opposing forces of labor and capital.

It appears that Jewison, Eszterhas and Stallone failed to bring out the best in each other. It's not unusual for promising, reputable projects to end up on the lumpy, droopy side because the key collaborators and/or ingredients just didn't jell. "F.I.S.T." may have been doomed by an artistic misalliance. Although the product of people with strong personalities, it fails to evolve into a movie with a strong, unifying dramatic personality of its own.

Stallone rewrote the screenplay, presumably to adjust the role of Johnny Kovak to his own intuitions and requirements. His touch is obvious in certain moments, especially the early courtship interludes with Melinda Dillon as the future Mrs. Kovak. Amusing as it can be, the limitations of the touch also are obvious: The repartee is unbalanced, because Stallone still can't write the woman's part with equal facility and isn't protected on this occasion by the pretense of a woman who's too shy to say much.

The only things approaching dramatic climaxes in the film are Stallon'e most intense and impassioned oratorical scenes, but overall his performance seems ill-conceived and unsatisfying. Utimately, it hardens into a stolid recollection of Lee J. Cobb as Johnny Friendly in "On the Waterfront."

What seems to be missing is the same emotional identification that give conviction to Stallone's portrayal of Rocky Balboa. There are flashes of humor and intesnity in some of his scenes as the youthful Johnny Kovak, but I doubt if Stallone ever fully comprehended or sympathized with this character, and it seems to drift away from him as the character ages.

But the essential problem seems to be in the writing. It's unlikely that either Eszterhas or Stallone succeeded in expressing anything deeply felt through the movies and times of a character like Johnny Kovak. The script is always too schematic to impose a convincing sense of the conditions in which he emerges as a labor organizer or involve us in the drives and contradictions that influence his behavior.

The film takes a methodical approach that uttimately stifles curiosity, because it persists in touching a lot of bases without revealing anything of crucial social or dramatic import.

The filmmakers seem to imagine that some sort of showdown is reached when Kovak is challenged by a smug, racket-busting senator played by Rod Steiger. For the life of me I could not understand what he felt so smug about, unless it was the egregious abuse of his authority as the chairman of a Senate investigating committee. As written and staged, the confrontation between crooked labor leader and self-righteous solon is a cacophonous bust, a shouting match without significance or resolution.

The filmmakers appear to be satisfied with the senator's declarations that "I'm worried about this country" and "Isn't it frightening to think of all that power in the hands of one man?" These seem rather laughable expressions of either social concern or political sophistication. Given the 20 years of nonreform that followed the hearings that supposedly exposed Jimmy Hoffa's leadership of the Teamsters, how could anyone take the senator's grandstanding seriously? Maybe his antics will hand a few laughs to Edward Bennett Williams.

"F.I.S.T." may be given patronizing credit for reflecting some vague desire to do an important picture about the perils of corruption within the American political system. Unfortunately, it can't be given credit for realizing that desire with much skill or credibility.