On a sweltering summer day in 1947, a brown-skinned man of medium height, sweating in a wool suit and sweater, pulled open the door of a San Francisco taxicab and told the surprised driver, in heavily accented English, "Take me to Notre Dame."

What followed was a classic breakdown in communication. The man, whose destination was the University of Notre Dame in South Bend, Ind., had neither the command of English nor the knowledge of American geography to keep the cabbie from dropping him off at a Catholic girls' school in Oakland called Notre Dame Academy.

In the ensuing 30 years, Vincente Blaz' command of English has improved. Enough, in fact, that two months ago, the U.S. Marine Corps promoted Col. Vincente Blaz to brigadier general and assigned him the task of rebuilding the badly battered image of the corps.

Blaz is a native of Guam and the first nonwhite to reach the rank of general in the Marines. He will not lead troops through hostile territory as director of Marine information but will face the equally difficult task of adapting the tools of a language he did not speak for the first third of his life to the vast public relations needs of the Marines.

Until recently, Blaz said last week, the Marines "never had to account ot the public, because our causes are so noble . . . We make the bets, and our lives are on the line. Not dollars, our lives."

Then came the Vietnam era, he said, and a precipitous and unprecedented drop in the prestige of all the military services.

When the war ended, the Marines' public relation problems were only beginning: the Ku Klux Klan controversy at Camp Pendleton; the case of a mentally handicapped 19-year-old recruit beaten fatally during boot camp, other revelations of mistreatment of recruits.

Blaz calls the incidents "aberrations" and argues that what the Marines need is not a radical change in their way of doing things, but a new attitude about the relation of the corps to society at large.

"The Marine Corps' mode of operation has withstood the test of time," he said. "It has served us well."

Internally, though, Blaz says, the Marines must open themselves to public scrutiny, to look at the corps as a corporation, with its generals as directors, the public as stockholders, and the media as daily auditors.

Blaz is a man well suited for the job of being the major link to the media and the public for the service with the reputation as the fiercest of the branches of America's military force.

"I'm a product of public relations," he said, starting with the aftermath of World War II, when a goodwill effort by several U.S. Catholic organizations provided him the opportunity he had been seeking to leave his native Guam.

When the 9th Marine Division liberated Guam in some of the bloodiest fighting of the war, blaz was a teenager living in a Japanese concentration camp.

Even today, he does not speak easily of that time.

"As a boy, I have stood behind barbed wire," he said. "After I got out, nothing looked the same again."

Blaz said he spent six months in the camp and saw two residents of his village beheaded by the Japanese.

"There was a pervasive genes of personal insecurity," he said. "That probably is more damaging to your feeling of well-being than hunger . . ."

The Japanese would "have a person dig his own grave, knowing that as soon as he finished, they're going to cut his head off," he said.

After the Americans liberated Guam, Blaz asked an American private how he could get to the United States.

What the private told him, he said, was that "the first thing you have to do is learn to speak English. He taught me a few words and told me, of all things, to listen to the radio, and talk as they do."

The future general took the advice of the private, and within a year, armed with a scholarship to Notre Dame and boat fare paid by the Rotary Club, set off on the 22-day boat trip from Guam to San Francisco.

When his cab driver let him off at the girl's school in Oakland, he said, he pulled his passport from his pocket, thrust it at a nun, and said "I think my papers are in order."

The nuns put him on a train, he said, and told him to get off in four days in South Bend.

Blaz spoke only broken English when he got ot Notre Dame, but with the help of the radio and the "Toward More Picturesque Speech" section of Reader's Digest he mastered the language.

Not surprisingly, Blaz is unusually fond of the Marine Corps, even for a general.

People would be amazed at the range, the spectrum, of the things we do," he said, citing a Christmas-time Toys for Tots program the Marines run."What is not known, generally speaking, is the compassionate Marine, the gentle Marine."