A congressional and city task force, trying to make statehood for the District of Columbia more palatable to Congress, yesterday proposed amending the city-approved constitution to eliminate guaranteed rights to abortion and unorthodox sexual behavior between consenting adults as well as guarantees of government-sponsored jobs and loans for all District residents.

A separate constitutional amendment passed by Congress in 1978 -- to give District residents two senators and a congressman but not the full sovereignty of statehood -- meanwhile will die in August.

Ratification of the amendment requires approval of two-thirds of the states by Aug. 22, but only 16 states of the 38 necessary have approved the D.C. voting rights amendment, and there are not enough legislatures left in session to make it possible to meet the deadline.

District voters approved the constitution of the proposed state of New Columbia in November 1982, as drafted by a D.C. statehood convention, despite concerns among many public officials that it was too controversial to get through Congress.

The task force, which has worked for about a year on proposed amendments to the constitution, included Charles I. Cassell, the president of the District's statehood convention who had supported the constitution as drafted, as well as representatives of the offices of Mayor Marion Barry, D.C. Del. Walter E. Fauntroy, Sen. Edward M. Kennedy (D-Mass.), the Statehood Party, and the D.C. City Council.

Fauntroy and Kennedy have introduced companion statehood bills.

Fauntroy, announcing the proposed changes, said he would hold hearings on them this month and plans to get a test vote in the House on the statehood bill at the end of this year or early next year.

There is little likelihood that the Republican-dominated Senate will approve statehood during this Congress for the overwhelmingly Democratic District, statehood supporters acknowledge. They pin more hopes on getting a Democratic majority elected to the Senate in 1986 and then putting statehood to a vote.

But many supporters, including Fauntroy, have said that statehood would have little if any chance of passage unless the constitution was amended, because it is viewed as too radical.

"My goal . . . is to have a document whereby statehood is the issue and not the document," Fauntroy said at a press conference.

Some controversial elements remain in the constitution as proposed by the task force, including homosexual rights.

But the revisions would change several provisions, most in the bill of rights section, that promised to draw intense opposition: A guarantee of a job for all District residents, which has been the subject of some of the harshest criticism, was stricken. A clause making the city government the lender of last resort for anyone wanting a loan was replaced with creation of a financial institution to facilitate loans to those who cannot get them through private sources. The right of all public employes to strike was modified to give this right to nonessential employes only, largely because of concerns if police officers and firefighters were included. A far-reaching prohibition against unreasonable searches and seizures was modified. Another provision was amended to allow for preventive detention of persons charged with serious crimes. Prohibition of grand jury "fishing expeditions" was eliminated.

A privacy section which included language intended to provide a constitutional right to abortion as well as to "noncommercial private, consensual sexual behavior of adults" was replaced with a simple clause stating that privacy shall not be infringed.

A detailed antidiscrimination section was simplified to guarantee equal protection regardless of race, color, religion, creed, citizenship, national origin, sex, sexual orientation, poverty, parentage, disability or age.

The D.C. voting rights amendment, as an amendment to the U.S. Constitution, required a two-thirds majority vote in both houses of Congress and approval of two-thirds of the states.

The statehood bill, including the constitution, would require a majority of both houses and with the revisions would have to be put to a final vote by District residents.