The Washington Bullets returned home yesterday from a five-day West Coast road trip with a three-game losing streak, a new starting guard and the possibility of changes involving three other players.

The winless stretch matches the team's longest of the season and comes on the heels of a period in which the Bullets were playing best basketball.

But the combination of a grueling trvel schedule and erratic guard placut Washington's Central Division lead to a half-game over the Cleveland Cavaliers and reduced its season record to 17 12.

Coach Dick Motta made his second major personnel change of the season Tuesday night against Los Angeles when he benched Kelving Grevey and finally gave veteran Phil Chenier his first start of the year, a move Motta described as permanent. Chenier responded with 18 points, making nine of 15 shots in Washington's 120-115 defeat.

For much of the game, Motta also used Larry Wright in place of Tom Henderson as the playmaker guard, a switch that reflects Motta's uneasiness over Henderson's inconsistent play.

Although it is unlikely Motta will bench Henderson, he now has decided to use Wright more frequently as long as the second-year man from Grambling continues to perform steadily coming off the bench.

Also in line for more minutes is rookie Greg Ballard, who returned home to the West Coast and responded with impressive outings against Portland Los Angeles. In the Laker game he ahd 10 points and guarded Adrian Dantley (who finished with 36) as effectively as any Bullet while playing 18 minutes, one minute less than his season-high against Portland.

Although Chenier's promotion was not unexpected - Motta had said for weeks it was coming - it still caused Grevey some unhappiness.

Motta had said Monday he would not bench Grevey after a one-for-eight shooting night against Seattle Sunday. "I don't like to make changes off a bad game," he said.

But he changed his mind Tuesday afternoon and went with Chenier, who had started the second half against Seattle.

"I think we had a better matchup against the Lakers' Lou Hudson with Phil," said Motta. "And I just thought it was time for him to start."

Motta also was hoping that by starting Chenier, he would receive more consistent performances from his star guard. It was apparent Chenier wasn't adapting well to reserve duty and was anxious to start again.

And, as one team source said, "They aren't playing Phil his large salary ($300,000 a year) to sit on the bench. He's supposed to start."

Grevey, however, had been a major factor in the Bullets' surge to the head of the Central Divison. The club won 11 of the first 14 games he started, during which he averaged 14 points. He started 17 games in all.

"I knew this was coming but I didn't think I was doing that poorly," said Grevey. "One game shouldn't affect everything else I've done.

"I just hope I don't become a forgotten man. I've earned my playing minutes and I don't want to lose them now."

Chenier said he welcomed the start, which ended a comeback from a preseason back injury and then difficulties adjusting to changes he said Motta had made in the offense.

"It makes a difference starting," he explained. "There is a lot of pride involved being on the starting team. It's a lot easier getting involved in the game when you are there from the beginning."

Chenier admitted he got very discouraged about sitting on the bench and finally talked to Motta about his status before the Bullets played Golden State a week ago.

"I felt like I was ready and I felt good but I was still coming off the bench," he said. "But he told me I would start eventually and to just be patient."

Ironically, Grevey had his mouth cut in the game against the Warriors and Chenier wound up playing his season-high in minutes. He responded with 25 points and t was evident from Motta's postgame comments that Grevey soon would be a sub.

At the other guard spot, Motta had hoped Henderson, who came over last year in a trade with Atlanta, would profit from a full trainig camp and become the consistent, steady play maker he feels the team needs to fully exploit its fron-court strength.

But HendersoN, a gifted athlete with fine quickness and strength, has been erratic. On the west coast trip, for example, he began with 16 points and six assists in 34 minutes against Denver, then didn't have a point or an assist in 20 minutes against Portland. He came back with a team-high 24 points and four assists the next night against Seattle, but he had just two points and one assist in a season-low 18 minutes against Los Angeles.

In the Laker game, he played only three minutes of the third quarter, committing two quick turnovers, before being yanked for the rest of the night Wright came in and finished with 17 points and had nine assists in 31 minutes. For the trip, Wright made 20 of 32 shots and had 20 assists.

Motta also would like Henderson to play betterdefense NBA sources say Henderson's defense is not as good as last season and opponents are trying to to work on him. The Bullets' leaky backcourt defense has hurt them all season.