A bill necessary to complete a new world trade agreement cleared another congressional hurdle yesterday, but its troubles are not over.

Legislation to waive penalty duties on subsidized imports, which European countries are deamnding before they will sign the trade pact, was approved by the Senate Finance Committee without a potentially crippling amendment, although senators reserved the right to amend the measure when it reaches the Senate floor shortly.

Sen. Bob Dole (R-Kan.) had proposed tacking onto the House-passed countervailing duty waiver bill an unrelated amendment to repeal controversial legislation that increases taxes on inherited wealth.

Bowing to appeals yesterday from U.S. Special Trade Representative Robert S. Strauss and Finance Committee Chairman Russell B. Long (D-La.), Dole agreed to hold onto his amendment in hopes another legislative vehicle for it will come along from the House. But if one doesn't before the waiver bill hits the Senate floor, Dole, who was supported by Sen. Malcolm Wallop (R-Wyo.), said he will probably try to amend the bill on the floor.

The Carter administration strongly opposes Dole's proposal and does not want to have to choose between swallowing it and vetoing the waiver bill, which Strauss describes as "absolutely essential" to the trade pact.

While Dole suggested the waiver bill could "stand one little amendment," Strauss said, "That would be like being a little pregnant... There's no such thing as a little amendment on my bill... We needed a clean [unamended] bill."

Dole's proposal, which reportedly has considerable support in Congress, would repeal legislation passed in 1976 but not yet implemented that has the effect of raising capital gains taxes on inherited property, estimated to cost heirs an additional $1 billion a year. Long indicated he might support Dole's proposal, although not as part of the waiver bill, and speculated there may be enough votes in Congress to override a presidential veto of it.

The waiver bill would extend the Treasury Department's authority to waive countervailing duties until Sept. 30 when it is expected the trade pact with its new subsidy penaties, will be passed last year but died in the pre-adjournment rush.

Fifteen waivers are currently in effect, covering such products as cheeses and butter cookies and involving about $35 million in lost revenues. The Treasury Department is requiring posting of bond or letters of credit pending congressional action on the waiver authority.

The administration is pushing for fast action on the waiver bill because the trade pact currently being negotiated in Geneva by nearly 100 trading nations is expected to be wrapped up shortly. In addition to lowering tariffs, the pact would reduce or eliminate a number of nontariff barriers to trade, including government subsidies of exports, procurement standards and licensing procedures.