The Federal Election Commission has filed suit against a Republican political action committee and its treasurer, prominent party fund-raiser Charles R. Black Jr., for allegedly failing to file financial reports about the committee's 1984 presidential fund raising.

The complaint, filed in U.S. District Court in Alexandria, alleges that the Alexandria-based New Republican Victory Fund and Black failed to file three reports and turned in a fourth one two months late.

Black could not be reached for comment yesterday.

The FEC has asked the court to impose fines on the defendants equal to the amount of money involved in the alleged violations, but not less than $5,000.

The suit does not say how much money is involved in the alleged violations.

Black, 38, was a senior adviser to President Reagan's 1984 reelection campaign and a political strategist for Sens. Jesse Helms (R-N.C.) and Phil Gramm (R-Tex.).

He was one of the founders, in 1975, of the National Conservative Political Action Committee and is a partner in the Alexandria-based political consulting firm of Black, Manafort, Stone & Kelly, whose clients include corporations, foreign governments and trade associations.

According to the complaint, the FEC tried to correct the alleged violations "by the informal methods of conference, conciliation and persuasion" with the fund's officials over a 30-day period. When that effort failed, the suit was filed.

The complaint states that under federal campaign laws, the treasurer of a political action committee must file quarterly reports of receipts and expenditures "in a calendar year in which a regularly scheduled general election is held."

The suit says that the committee filed one report 64 days late and did not turn in three other reports.