Steaming 98-degree heat, a savage thunderstorm that forced a 95-minute delay and the absence of many advertised stars made the Liberty Bell Classic less than a ringing success when it opened as a much-advertised "Alternative Olympics" today at Franklin Field.

Still, a crowd of 3,181 turned up for a few sprint trials and competition in the men's decathlon and women's pentathlon. The fans responded with enthusiasm to whatever they were given to cheer.

Principally, they reveled in the brilliant efforts of Marlene Harmon, a 17-year-old California schoolgirl who finished second in the pentathlon, and Lee Palles, a 24-year-old accountant out of Mississippi State who took the first-day lead in the decathlon.

Harmon, blond pigtails flying, won the 800 meters, the concluding event, in 2:10.17 to edge teammate Linda Waltman and post the third-highest score ever by a U.S. pentathlete, 4,346 points. She achieve personal bests today in the 100-meter hurdles the high jump and the 800.

The pentathlon winner, as expected, was Canadian veteran Diane Konihowski, who rolled up 4,640 points. Her victory was tarnished, however, by the withdrawal of West Germany's Cornelia Sulek, who suffered a back injury in the fourth event, the long jump and could not run the 800. She trailed Konihowski at that time by only three points. American Marilyn King dropped out after one event with an Achilles tendon injury.

"The shot put is holding me back, but when I get it, I'll get up with everyone else," said Harmon, who finished last in that event while dropping 286 points to Konihowski.

Harmon, 5 feet 10 and 127 pounds, will take her time making up the shot gap, since she sprained her back attempting a four-hours-a-day shot program in March. She has four years to practice and mention of the 1984 Olympics in Los Angeles brought a bright smile. "Oh, yeah, I'll be ready then. It's going to be a blast."

Konihowski tried to be a gracious winner, but mention of the Olympics prompted her to say, "I'd just love to be there. I think everyone would. It's in the back of my mind, but I can't stew over it."

The storm struck just as the women completed the long jump, giving them extra time to rest for the 800. The men were competing in the high jump, eventually won by Palles at 7 feet.

Guido Kratschmer of West Germany, the world record holder in the decathlon, was affected by the heat and cleared only 6-2 1/2. Kratschmer was fourth after the five events with only 4.104 points. He recorded a first-day total of 4,460 en route to his record of 8,649 in June.

Palles, 6-4 and 205, led with 4,272, followed by German Jens Schulze, 4,136, and U.S. champons Bob Coffman, 4,135. Palles was pleased but not supremely confident.

"I'm really a first-day man," Palles said. "I just haven't improved enough to get 4,000 points the second day. I expect Kratschmer to come on like a storm and Schultzie's hot. So is Bob. I don't want to say it's inconceivable for me to win. I'd like to be in there."

Two struggling West Germans, Jurgen Hingsen and Wolfgang Muders, withdrew after three events. With other West Germans missing, notably sprinter Annegret Richter and 400-meter star Harald Schmid, there were some snide comments about the Germans' commitment to the meet. But Americans Tony Darden and Willie Smith were no-shows, too, so blame for the disappointment had to be shared.

"You want to have the best field you can to run against, so not having the Germans hurts," said 400-meter qualifier Herman Frazier. "But we beat them in a relay five or six days ago, and we'll meet them again."

The sprint fields were filled with names like Banana Jarju, Fabian Whymns, and Fadi Alla Ali Mudawi, but 100 meter qualifier Harvey Glance said that was not necessarily bad. "It's a chance for them to compete against world-class people. A lot of them wouldn't have qualified for the Olympics."

Besides the pentathlon, the lone title decided today was in the 10-kilo-meter walk, won by American Dan O'Connor. The only foreign entrant, Italy's Alessandro Pezzatini, dropped out.

The decathlon concludes Thursday, starting at noon, with individual weight events beginning at 2 p.m. and the running finals starting at 5:30. White House counsel Lloyd Cutler, considered by many athletes the architect of the Olympic boycott, will be present.