Just 18 months ago, Jimmy Carter told a Louisville audience of his concern over the "devastating loss of respect for our nation" that results from the appointment of a president's political pals to ambassadorships.

It is an insult to the United States, he told an applauding audience, when the U.S. ambassador is "a fat, bloated, ignorant, rich, major contributor to a presidential campaign who can't even speak the language of the country in which he serves."

Carter promised that if elected, he would increase the percentage of ambassadors chosen from the career Foreign Service.

Yesterday President Carter chose one of his former fellow governors, John C. West of South Carolina, to be ambassador to Saudi Arabia. It was the latest of several ambassadorial appointments that seem inconsistent with Carter's campaign pronouncements.

Of 37 ambassadors selected by Carter, 17 are non-career people.

However, this percentage is almost certain to decline as appointments are made to the many smaller embassies as yet unfilled, and Carter officials stress that their non-career choices are not bloated, not inexpert, not political cronies of the President.

"Obviously not," White House press secretary Jody Powell replied when asked if Carter had changed his mind about ambassadorial appointments. "You ought to check the numbeer of them who already know the language and the country to which they're assigned."

"The relevant comparison is to the number of career appointments in the past," Powell said.

In the Nixon administration, 32 per cent of ambassadorial appointments were non-career people, according to the American Foreign Service Association (AFSA).

President Ford's choices were 38 per cent non-career.

AFSA, which has long advocated giving more ambassadorships to career people, was delighted by Carter's campaign promises.

Now, AFSA President Patricia Woodring refers ruefully to Carter's criticism in his book "Why Not the Best" of "the disgraceful and counterp-productive policy of appointing unqualified persons to major diplomatic posts as political payoffs."

Carter wrote: "This must be stopped immediately."

"Our inclination is to be discouraged at this point," Woodring said. But AFSA has not abandoned hope that the appointments yet to come will please it more. Nor is it opposing all Carter's non-career choices.

"We recognize the importance and even the desirability of having expertise come in from outside," Woodring said. "But they must be qualified."

Only five of the 17 non-career choices are opposed as unqualified by AFSA, including one that has not been officially announced yet, Sally Shelton, 32, as ambassador to El Salvador.

Shelton has drawn opposition because of her youth and apparent lack of foreign affairs experience. She is a legislative assistant to Sen. Lloyd M. Bentsen Jr. (D-Tex).

Two of Carter's wealthy Georgia supporters, Anne Cox Chambers and Philip Alston, and two early Carter supporters in Ohio, Marvin Werner and Milton Wolf, have also brought serious objectives from AFSA.

Chambers, who owns Atlanta's newspapers, has been named to Belgium, Alston to Australian, Warner to Switzerland and Wolf to Austria.

Although AFSA believes ambassadors should have foreign affairs experience, it has not objected publicly to appointments like that if Wisconsin Gov. Patrick Lucey to Mexico because he has performed public service that makes up in part for his lack of diplomatic background, Woodring said.

Her organization has been making its objections known to the White House, Woodring said. "We have been told that the President was upset with us at one point," she added. "At least that means he's reading our material."

National Security Council spokesman Jerrold Schechter said that Carter's non-career appointments include blacks and women to a greater degress than those of his predecessors. In addition, he said, Carter was seeking people who represented aspects and regions of the United States, not just political associates.

Carter established a review commission to recommend candidates to him. According to Schechter, the President gets a list of from six to ten names for each embassy from the commission. The lists are roughly half career and half non-career.

After Carter and Secretary of State Cryrus R. Vance confer, the choice is narrowed down to a couple of names from which the President makes his final choice.

Of the review commission's 20 members, four have foreign affairs experience. AFSA has been critical of the commission for the not including any career ambassador.

West, 54, was a neighboring governor when Carter was in the Georgia governor's mansion. He headed a South Carolina trade mission to Saudi Arabia in 1976 after leaving office, but is not widely experienced in foreign affairs.

Woodring said it has not been West's appointment.