"I came here to listen," Andrew Young said about his much-heralded diplomatic mission to Africa as new U.N. ambassador. So far, it had been difficult to find anyone who will talk.

The turn of events in Africa since Young left the United States on Tuesday has been so significant that his 10-day journey appears to be increasingly anticlimatic.

Young expected to confer with 25 African presidents during stops in Zanzibar and Nigeria to hold talks on the increasingly troublesome Rhodesian issue and a new U.S. role in Africa.

But a coup in Ethiopia, the bitter collapse of the East African community - of which host-country Tanzania is a member - and the annoucement by the Rhodesian government of its plan to implement majority rule without international backing have all stolen the show.

Only five presidents have shown up on Zanzibar - down by one because of the Ethiopian coup - for the celebrations of the merger of the political parties of the island and mainland Tanzania that brought Young to East Africa. This morning, Young told the almost two dozen reporters clustered about him. "I plan to just hang around the (hotel) door and grab as many presidents as possible as they come in."

The statement reflects to some degree Young's low-key, unpretentious diplomatic style. Observers here are beginning to wonder however, whether it also reflects a lack of interest by Africans in new U.S. involvement in the problems of the continent.

At least 200 Zanzibari dancers, singer and musicians and a guard of honor greeted delegations arriving today. Young was received yesterday only by a junior foreign ministry official. The Tanzanian government has scheduled something specially for him.

It is still not certain when or where Young and Tanzanian President Julius Wyerere will meet.

Young had so much free time in his first 24 hours on the island that his only major activity was a game of tennis at the local 'people's club' wih his aides.

When he was approached by two Tanzanian officials in the hotel today who asked if he needed help, Young responded, "Do you know where I can find (Zambian) President Kaunda?"

Later in the day, Young had his first contact with African leaders at an evening banquet, where Tanzanian President Nyerere spoke. Young met Kaunda there, but only informally.

U.S. officials even admitted they had to push the Bwawani hotel, the island's only Western-style tacility, to get rooms for Young and his four aides.

The new ambassador, who was sworn in only last Sunday, tried to strike an optimistic note during a briefing with reporters today, explaining that he had no specific intentions, but just wanted to be available for talks during his tour.

He said he wanted to hear what the so-called front-line presidents - the five chiefs of state involved in the Rhodesian settlement effort - had to say "in their quieter moments" to assess the difference between what they preached in public and what their speific policy is.

From his experience in the civil rights movement, Young said he remembered how American blacks shouted "freedom now" but in private outlined priorities and moderate transitional steps toward full civil rights.

He said he expected the same was true of the demand by the presidents of Tanzania, Mozambique, Botswana, Zambia and Angola for immediate majority rule in Rhodesia.

Young refused to accept that the settlement effort launched by former Secretary of State Henry A. Kissinger has collapsed. Young said he hoped he could find points of flexibility that might lead to renewed peace talks.

The former Georgia congressman said the problem centered around the fact that Rhodesian whites, Asians and persons of mixed race felt the British settlement proposals, an alternative to the original Kissinger plan, did not provide enough long-term security.

Since the British proposals have been accepted as a basis for renewed negotiations by the Rhodesian nationalists, the problem was to find a means of reassuring whites of their future under a black government.

But Young made the statement just hours before Rhodesian Prime Minister Ian Smith announced the steps his government would take to implement majority rule without international backing under the two year outline of the original Kissinger plan and excluding the militant black nationalists involved in previous negotiations.

Young admitted: "I can always see hope where there is none."