Frustrated that their advice on transit matters often is ignored, members of the D.C. Council came within two votes yesterday of blocking the appointments of the city's representatives on the Metro board of directors.

The debate over the appointments for 1978 had overtones of election-year politics, with the council's two announced mayoral candidates - Marion Barry and Sterling Tucker - trading verbal punches.

Barry (D-at large) wanted to know why the city's representatives do not always follow instructions from the council on how to vote at Metro meetings. He cited last year's increase in the rush-hour bus fare from 40 cents to 50 cents, which a council majority opposed.

Tucker, the council chairman, who resigned last week as a Metro director, said the city's representatives at Metro must be free to use their best judgments in negotiating with suburban directors on regional issues.

Council member David A. Clarke (D-one) complained of Metro's possible scuttling of plans for a subway in the Columbia Heights area of Northwest Washington. He also objected to "this idiotic train-bus interface (transfer) system," which he said is alienating riders.

Most council complaints dealth with last year's bus fare increase, which was adopted with the approval of the city's two alternate directors of Metro, council member Jerry A. Moore Jr. (R-at large) and D.C. transportation director Douglas N. Schneider Jr. Alternate directors may vote at Metro only if the city's principal directors are absent.

Yesteray's debate was triggered by Tucker's resignation from the Metro board, and his nomination of Moore to succeed him as a principal director. Tucker also nominated the council's chairman pro tem, Willie J. Hardy (D-seven), to fill Moore's slot as alternate.

The other nominations were for the reappointment of Mayor Walter E. Washington as principal director and Schneider as alternate.

After an hour of debate, Hilda H. Mason (Statehood-at large) sought to table - and possible kill the nominations. The vote was 7 to 5 against, with Mason joined by Barry, Douglas E. Moore (D-at large), Wilhelmina Rolark (D-eight) and John A. Wilson (D-two). The nominations were then approved by a vote of 10 to 2.

In other matters yesterday, the council:

Extended rent control, on an emergency basis, for 90 days to give Congress time to review the recent three-year extension of the city's basic rent control law.

Approved, on an emergency basis, a resolution initiated by Barry, barring the spending of any D.C. government funds for conventions or meetings in any of the 15 states, including Virginia, that have not ratified the Equal Rights Amendment.

Voted the council's own symbolic, but not legally effective, ratification of the Equal Rights Amendment.

Voted the council's own symbolic, but not legally effective, ratification of the Equal Rights Amendment.

In a related matter, the major announced that he had vetoed - on technical grounds - a council-passed bill that would restrict the conversion of apartment buildings into cooperatives. Washington invited the council to pass a correct bill promptly, and said his veto should not have any harmful effect on the housing market.

Similar legislation has been enacted that restricts the conversion of apartment buildings into condominiums. That bill was not affected by the new veto.