It is nice to claim that the Washington Capitals are improved. Fans who have watched the club through five losing seasons require some convincing, however, and they were given none last night.

Many among the 8,125 Capital Centre spectators showed their skepticism with boos as the Capitals dropped a 3-1 exhibition decision to the Hartford Whalers.

Rookies Bengt Gustafsson and Mike Gartner, playing here for the first time, found themselves subjected to verbal abuse instead of an open-arms welcome. They were targeted for criticism during a full minute early in the third period when Washington had a two-man advantage and they were unfortunate enough to send the puck out across the Hartford blue line.

In other days, there would have been no crowd reaction. This time the fans let all concerned know that they were weary of waiting for better things.

Matters deteriorated after that manpower edge failed to alter a 1-1 tie. Dave Keon, the 39-year-old center who figured in all three Hartford goals, shattered the deadlock with a back-hander from the slot, after some sloppy play by the Capital defense.

While the Capitals were rocked back on their heels, the Whalers swept past them. A Keon setup sent Jim Warner behind the defense and, after he pulled goalie Gary Inness to one side, he fed Bill Bennett for an easy score.

Victimized on all three Hartford goals was Pierre Bouchard, who had raised eyebrows in the first period by three times permitting Whalers to skate around him. Wayne Stephenson, the starting goalie, foiled each sortie in a 30 1/2 minute, eight-save shutout performance, but there must now be some concern about the 31-year-old Bouchard's mobility.

Faceoffs are another potential problem. Keon won a bundle in the last two minutes, after Coach Danny Belisle yanked Inness for a sixth skater in a vain bid to give the folks a lift before they passed the ticket windows on their way to fresh air.

"Who Unscrewed the Caps? 6-1-1" read a large sign at one end of the rink. It was written in positive vein, but the author might have been searching for another reply by game's end, with the exhibition record now 6-2-1 and the rising fear extant that possibly the Caps are still unsettled by home cooking.

One bright spot was the work of the original Cap, Yvon Labre, although he was not celebrating. Labre was sandwiched by Alan Hangsleben and Jordy Douglas and needed to be helped to the dressing room. Unlike the Capitals image, he was not seriously hurt.