The last time the Washington Capitals scored more than two goals was Dec. 18, in a 5-3 victory at Pittsburgh. It was the Capitals' third straight success against the Penguins and led certain Capital Centre noncombatants to transform the ornithological nickname to Pigeons.

Pittsburgh visitsd Capital Centre tonight at 7.30 and if ever a team needed a pigeon, the home club with just 12 goals in its seven games, is it.

Pittsburgh, however, has spread its wings in the last 10 days, sweeping through its last four games in unbeaten fashion. It is unlikely to prove complacent, with haunting memories of those last three Capital conquests, as well as the more recent vision of Vancouver's last minute goal that cerated a 2-2 tie Tuesday.

Washington was similar victimized Tuesday, Detroit earning a 2-2 deadlock on Dwight Schofield's goal with two minutes to play. Max McNab, the Capital's general manager, spent the night after that one rolling around in bed unable to rationalize the loss of that extra point in the team's desperate pursuit of Pittsburgh and Los Angeles.

"It really keeps you awake at night,"McNab said yesterday. "We need a group therapist some nights. With one or two guys you can adjust, but when everybody goes stiff all at once, it's really frustrating. Maybe it will wake them up for Pittsburgh. That's a big one for us.

Coach Tim Mcvie slept somewhat better, although baffled by the Capitals' flat performance in a game in which they figured to be flying.

"The inspiration was there," McVie said. "I almost had to lock the door to keep them in there before the game. Then nothing, if I knew the answer, I wouldn't have to coach. I'd be a trouble shooter for all the other teams that run into the same problem."

McVie ran into further proablems yesterday, as he attempted to conduct a selective practice for those he felt needed the work. Arriving at the Fort Dupont rink in Southeast Washington for the 10:30 a.m. session, McVie and the players encountered locked doors.

"The people who manage the rink didn't show," McVie said. "There was a lot of traffic snarled on the way, but all these Canadians can drive in the snow. They all got through, but there wasn't much I could do, except have them run around the parking lot in the show. It was an act of God, I guess."

After Tuesday's performance, running in the snow must have been a tempting punishment, but instead McVie ordered his charges back to Capital Centre for some indoor exercise. The Centre ice was unavailable, of course, because of the Bullets' game last night.

Ron Schock, who failed on a penalty-shot attempt against goalie Bernnie Wolfe on the Penguins' last visit Nov.30 (Washington won, 6-4), is the hottest of the visitors. Schock, the Penguins' captain, has scored goals in the last three games for a season total of eight. He will be playing his 273d straight contest tonight.

Pierre Larouche, no longer the 53-goal Lucky Pierre of last season, will be along on this trip, after missing the Nov.30 visit while serving a sentence on the Hershey farm for insubordination. Larouche, who has 13 goals in 27 games, was quoted Tuesday as saying, once again, "Trade me, I'm starting to hate hockey."

"Trade" is a magic word that perks up McNab and, if Penguins general manager Baz Bastien is in attendance tonightM Larouche just might be a topic of conversation between the two. The thought of a talent like Larouche motivated by a disciplinarian like McVie is enough to make any general manager salivate.

Denis Herron will be the Pittsburgh goalie, ending a policy of alternation with Dune Wilson. Herron will be playing his second straight contest so that Wilson can face his Chicago cousins, whom he shut out earlier, on Saturday.