Labor Secretary Ray Marshall endorsed the idea of automatic increases in the minimum wage yesterday and said the Taft-Hartley Act, which he described as a "bad thing for labor," should be streamlined.

In both cases, he aligned himself generally with major legislative goals of organized labor for this year, although he did not commit himself to the specifics of either idea.

On the minimum wage, Marshall said he sees "a lot of merit" in tying automatic future increases in the wage floor to some index of wage levels in general, rather than having Congress change the minimum by statue every fews years as it does now.

The current minimum is $2.30 an hour for most workers. The AFL-CIO supports a $3 minimum with indexing for future increases. A bill-now before Congress, which was attacked Tuesday by a spokesman for the U.S. Chamber of Commerce as a threat to econcomic recovery, would set the minimum at 55 per cent of average manufacturing wages this year and 60 per cent thereafter. This would work out to $2.85 this year and an estimated $3.04 next year.

At a breakfast question-and-answer session with reporters, Marshall said the minimum wage has been lagging increasingly behind living costs in recent years.

Indexing would help keep the minimum wage abreast of living costs, he added, and avoid "legislative conflict" everytime an increase is needed.

The minimum wage was last changed in 1974 when it was raised from $1.60 to $2.30 in a series of steps. An estimated 10 million workers, more than 10 per cent of the work force, now earn less than $3 an hour.

Marshall said it was time for a "major look" at the Taft-Hartley Act, which was passed in 1947 over objections by labor that it curtailed many rights that unions had won during the 1930s. He "some streamlining" of the act.

The law outlawed secondary boycotts and jurisdictional strikes, permitted states to enact right-to-work laws outlawing union shops and imposed othe restrictions on union activity. "I think, on balance, you'd have to say it's been a bad thing for labor," said Marshall, especially in organizing and negotiating contracts in the South, among agricultural workers and in low-paid trades.

Marshall indicated he favored efforts to curb delays in union representation elections and contract negotiations but said he wasn't sure how much could be done through administrative action rather than legislation.

While "there does seem to be some need for change," he said, "I don't know if I'd call it drastic." But then he said that he doesn't consider repeal of Section 14(b), which permits right-to-work laws now in effect in 20 states, to be a "major" change - a point disputed by conservative groups that are already mounting a massive campaign to save 14(b).

Rep. Frank Thompson (D-N.J.) has introudced legislation in the House to modify Taft-Hartley and a bill incorporating the AFL-CIO's stand on the issue, including repeat of 14(b) is expected to be introduced shortly in the Senate.

Asked about the Labor Department's probe of the Teamsters' pension fund, Marshall said Court action is still possible, especially if Teamsters President Frank Fitzsimmons and three other trustees don't resign as scheduled under an agreement to overhaul management of the fund that was announced Sunday.The government's target date for the resignations is April 30.

Marshall said he refused to testify at a congressional hearing on the government's probe of the pension fund earlier this week because he received legal advice from Attorney General Griffin B. Bell and others that any testimony that became public might jeopardize the government's case in court.

Marshall said Fitzsimmons agreed to resign because "I think we persuaded him it was in his best interest to step down." This was at odds with a statement issued yesterday by Fitzsimmons who said he intended as long as October to resign. Said Marshall: "We told them (the trustees) we'd go to court; we had a strong case."