Deadlocked 8 to 8, the Senate Foreign Relations Committee yesterday refused to recommend that the Senate block President Carter's proposed sales of warplanes to Egypt, Israel and Saudi Arabia.

TThis was a victory for the president, whose aides had expected as recently as last week to lose decisively in the committee.

But yesterday's votewas not conclusive, because planes sales opponents convinced the committee that despite its inability to agree, the full Senate should be given a chance to consider the issue. Senate leaders then scheduled an all-day debate for Monday, with a vote expected late in the afternoon.

Democratic and Republican leaders in the Senate say their headcounts show a majority will support Carter in Monday's vote. Opponents of the sales, including members of the Senate and representatives of jewish groups who have lobbied against the transactions, predicted a close vote.

The Conference of Presidents of Major Jewish Organizations in New York reacted to yesterday's committee vote by sending telegrams to all members of Congress urging rejection of all three sales. The embassy of Israel in Washington issued a statement saying it too opposed the "package deal."

Opponents of the sale who a fortnight ago argued forcefully against the concept of a "package" - in which sales to the three Mideast countries all depend on each other - yesterday avidly adopted that concept.

They argued that the Senate should consider the sales together to avoid embarrassing any of the three countries with a floor debate on the merits of its particular sale. Some opponents of the sale have now decided that the "all-or-nothing" choice offers the best opportunity to defeat the package, since it implies equal treatment of all three countries.

The Senate may get the all-or-nothing choice, although Majority Leader Robert C. Byrd (D-W.Va) will try to avoid that with a vote on a motion to indefinitely postpone further consideration of all efforts to block the sales after an all-day debate. Informed sources disclosed Byrd's tactic yesterday.

A vote to postpone would have the practical effect of allowing the sales to go ahead.

Under the arms sales act, a proposed transfer can be blocked by a concurrent resolution of the House and Senate within 30 days of notification of the sale from the executive branch. The 30-day period will expire before the Memorial Day recess.

President Carter late yesterday called a meeting of senior administration officials to urge them to do all they could to win over Senate votes by Monday. Cabinet officers including Cyrus R. Vance, the secretary of state, and Harold Brown, the secretary of defence, will be visiting undecided senators or talking to them by phone during the next three days.

The administration expects supporters of Israel to work intensively to win votes during the same three days.

There were hints of the intense pressure senators have felt on the issue during yesterday's meeting of the Foreign Relations Committee. At one point Sen. Charles H. Percy (R-ILL) said he thought the Senate should have the same "opportunity" to weigh the plane sales issue that committee members had had - a line that drew hearty laughter from his colleagues.

Percy said a report in yesterday's New York Times mistakenly listing him as one of two undecided committee members had elicted a vast number of phone calls yesterday morning. In a written statement later, Percy thanked several Jewish leaders byname for helping him understand the issues.

Percy voted in favor of the plane sales, contrary to the wishes of many of those he had been hearing from.

Informed sources said Sen. Muriel Humphrey (D-Minn.) had been heavily pressured Wednesday night and Thursday morning to change her vote after it became known that she also planned to support President Carter and the sales. The lobbying continued until just befor yesterday's vote. Her Minnesota colleague, Wendell R. Anderson (D), summoned her from the committee-room dais yesterday morning to urge her to vote against the sales.

Humprey reportedly wavered at the last minute, but ended up voting for the sales. Besides Humphrey and Percy, the senators supporting the sales were CommiCommittee Chairman John J. Sparkman (D-Ala.) George McGovern (D-S.D.), John Glenn (D-Ohio), James B. Pearson (R-Kan.), Robert Griffin (R-Mich.) and Howard H. Baker Jr. (R-Tenn.).

Those voting against all three sales were Frank Church (D-Idaho), Claiborne Pell (D-R.I.), Joseph R. Biden (D-Del.), Dick Clark (D-Iowa), Dick Stone (D-Fla.), Paul Sarbanes (D-Md.), Clifford Case (R-N.J.), and Jacob K. Javits (R-N.Y.).

Strong sentiments against the sale were expressed by several members. Sarbanes noted that President Carter's latest compromise - adding 20 more F.15s to the 15 F15s and 75 F16s offered to Israel in the package - would raise the total value of the three sales to about $6 billion.

Sarbanes called this a striking figure in light of President Carter's rhetoric decrying America's role as arms merchant to the world.

Stone said opponents of the sale did not want to "rebuff the Saudis" or deny them American defense aid, but rather to hold off these sales now to encourage the Mideast peace process.

Perhaps the administration's most effective argument in favor of the sale has been that the United States had to help the "moderate" Saudis at this time to demonstrate support for a regime whose oil and financial resources could be critical to America.

The general argument that the U.S. must show support for moderate Arabs as well as Israel has attracted one senator known in years past for his staunch support of Israel - Abraham A. Ribicoff (D-Conn.). Ribicoff will speak in favor of the package Monday.

Proponents and opponents of the sales think this is important, because senators who would like to vote for the sales but fear the anger of Jewish constituents can point to Ribicoff's position as a justification for their own.

Some officials of pro-Israeli organizations here bitterly attack Ribicoff in private, accusing him of "selling out" to Carter or seeking an ambassadorship when his Senate term ends in1981.