President Carter and Israeli Foreign Minister Moshe Dayan disagreed in public again yesterday about whether the Egyptian-Israeli peace talks have run into serious problems.

Echoing the pessimism that he first expressed Tuesday, Dayan told the president, in the presence of reporters, that the chances of the delegations negotiating here being able to resolve their differences are "very doubtful."

But Carter, who said Tuesday that there was "no crisis" in the talks, continued to sound optimistic yesterday. He told reporters, "We don't have any particular problem."

Their sharply contrasting comments gave new impetus to the speculation going on since Tuesday about whether the effort to work out an Egyptian-Israeli peace treaty is in danger of deadlock.

Sources familiar with the negotiations, while generally shying away from the gloomy language used by Dayan, still say that some sharp and so far intractable differences divide the sides.

According to the sources, difficulties persist over Egypt's demand that Israel commit itself to the principle of eventual withdrawal from the West Bank and Gaza Strip - two areas whose future status, together with that of their Palestinian Inhabitants, is outside the scope of the proposed Egyptian-Israeli treaty.

However, Israel contends that, in accordance with the decision taken at the Camp David summit to treat these areas separately, their future should be decided after the current peace talks are concluded.

Another sticking point is understood to involve Israel's insistence on full diplomatic relations with Egypt after Israel begins withdrawing its forces from the Sinai peninsula. Egypt, concerned about adverse reactions elsewhere in the Arab world, reportedly wants to move more slowly.

Other reported points of dispute relate to the amount of U.S. financial support that will be extended to Israel to help pay for its withdrawal from Sinai under the terms of the Camp David agreements.

Israel is seeking aid to cover the costs of relocation of Israeli settlers in the Sinai who would be subject to eviction by the Egyptians. The United States has also agreed to help finance relocation of two Israeli military air bases from the Sinai to the Negev.

Washington Post Correspondent William Claiborne reported from Jerusalem yesterday that the Israelis also are balking at an Egyptian proposal to automatically reopen the treaty for review after five years.

Claiborne quoted Israeli government sources as saying that Prime Minister Menachem Begin has instructed his negotiators in Washington to reject the idea. Begin reportedly took the position that a peace treaty by definition should be eternal and can only be repoened y mutual consent.

It was against this background of unresolved ussues that Dayan and Carter gave their differing assessments of the negotiating progress during a luncheon at Blair House yesterday.

With reporters observing the start of the luncheon, Dayan, who was seated beside Carter, told him, "Whether you can obtain a change of position through the delegations here is very doubtful. It's not Camp David with the heads of state.

Carter replied: "I recognize that's one of the problems. I will trust your advice."

Later, though, as Carter was crossing the street to the White House, he told reporters the luncheon meeting had invalved "just routine negotiations" and added. "We don't have any particular problems."

Since Tuesday, when Dayan first spoke out publicly about difficulties, the White House has been working hard to dispel speculation about the talks being in trouble. That effort was continued yesterday by White House press secretary Jody Powell who took great pains to caution reporters against putting too gloomy an interpretaton on Dayan's remarks.

"I know of no information that would support a conclusion of a deadlock," Powell said.

Referring to what Dayan told the president at lunch, Powell said. "I think he was talking about not a specific problem with the negotiations but a general situation in which you have the delegation representing heads of government as opposed to the heads of government themselves. The process of movement back and forth, of making modifications, becomes more complicated and difficult under those circumstances."

His words seemed to support an inference that Dayan feels the negotiators here do not have sufficient flexibility in the instructions they've received from their governments and that Carter might have to draw Begin and Egyptian President Anwar Sadat directly into the talks to overcome the impasses.

However, the White House said Wednesday that Carter has not had any direct contact with Sadat or Begin in since the negotiations began here a week ago.

In his report from Jerusalem, Claiborne said Israel is preparing to send an emissary to Washington to obrief its delegation on what kind of access Israel wants to crude oil pumped from fields in the Sinai after Egypt resumes control of the area.

George Sherman, official spokesman for the peace talks, confirmed a report in yesterday's Washington Post that Egypt has agreed in principle to sell Israel Sinai oil as part of the peace settlement.

However, Claiborne quoted Israeli officials as saying a dispute still exists over whether Israel will get preferential treatment in the purchase of oil because of its heavy investment in developing the fields. The Sinai currently supplies approximately 15 percent of Israel's oil needs.

At the United Nations, Egypt, in a conciliatory gesture toward Arab states opposing peace with Israel, joined yesterday in sponsoring a resolution seeking an arms embargo against Israel. If such a resolution reaches the Security Council for asction, it is certain to be vetoed by the United States.