At times yesterday the marathon hearing before the Maryland Senate's Constitutional and Administrative Law Committee resembled an epic battle scene from "King Kong," with two powerful giants -- the railroad lobby and the truckers -- pitted against each other.

The focus of their struggle is proposed legislation that would increase the amount of freight trucks can carry when they travel on Maryland roads. The measure inevitably would make life easier and more profitable for the truckers, and therefore harder for their competitors, the railroad industry.

"The very great majority of witnesses that came in to testify in the first hearing last week were from industry," Committee Chairman Edward T. Conroy (D-Price George's) said yesterday. "The major opponents of the bill were the Chessie system and Con-Rail. . .

"And obviously there's a distinct economic advantage (for truckers) here; otherwise they wouldn't put this kind of effort into it."

"This kind of effort" meant that, during the two separate hearing and the 6 1/2 hours of testimony, the trucks and representatives of the industries whose products they haul -- chicken growers, tool manufacturers, supermarket chains -- came out about two dozen strong to support the bill.

The word "profits" almost never came up during the testimony. Witnesses talked instead about being competitive with the trucking industry in other states about the potential for new job, if the load limit legislation were to pass.

Other witnesses talked about stress factors, about axie loads and complicated engineering equations, about the fatal accident rate of heavily loaded trucks, and about broken bridges and pothoies.

But the key testimony, according to senators on the committee, came from the state Department of Transportation, which has opposed similar legislation in the past. Its contention has been that raising the allowable weight limit from 73,000 to 80,000 pounds would result in severe damage to Maryland's roads and bridges.

This year, department representatives agreed that the 80,000-pound limit would be acceptable because the legislation proposed by Sen. E. Homer White Jr. (D-Wicomico) specified that 80,000-pound loads could be carried only on trucks with five or six axles.

TRansportation experts said the department shifted its stand because the amount of weight per axle, and not the full weight of the truck, is the determining factor in damage to roads and bridges, and because the specified axle weight limits would not cause real harm.

With one of their key opponents now turned into an ally, the truckers and their friends redoubled their efforts to bring Maryland's weight load limit into conformance with other states on the major East Coast trucking corridor.

"Maryland alone blocks the movement of 80,000 pounds from Florida, Georgia and the Carolinas to and from the New York and New Jersey area," Giant Food's public affairs representative Barry F. Scher told the committee last week.

Edward E. Blazek of the Maryland Transportation Federation added, "The increase in truck weights has the potential of saving enormous amounts of energy."

However, James Bower, a representative of the Chessie System, one of Maryland's major railroad lines, responded yesterday that, "We feel there is a considerable overemphasis on the maximum energy savings."

Sen. Conroy then asked Bower, "Wouldn't the Chessie system lose freight if this bill went into effect?"

"We would not lose freight," Bower replied. Then, after a pause, he added, "We would be put at a competitive disadvantage."

Allied with the railroads in opposition to the bill was the American Automobile Association.

An association official quoted a study from the Bureau of Motor Carriers that "the heavier the truck, the more passenger car occupants killed in the event of a collision."

The committee is expected to vote on the legislation late next week.