Legislation overhauling regulation of the ocean shipping industry is delayed in the Senate because of a partisan fight over the appointment of Illinois judges.

As a result, the Ocean Shipping Reform Act, which had been scheduled for Senate action last week, is not likely to come up for a vote until at least Wednesday, and may well be delayed longer unless a quick resolution to the fight over judges is achieved.The shipping bill is backed by major ocean carriers and big U.S. importers. It would allow confidential shipper-carrier contracts and prohibit rate-making conferences from blocking independent action by their member vessel operators.

The fight over judges came to a head on the Senate floor Friday as Sen. Richard Durbin, D-Ill., engaged in a game of political hardball with Senate Majority Leader Trent Lott, R-Miss., who is a key backer of the shipping bill.

Because Senate approval of two federal district court nominees from Illinois, who have been approved by the Judiciary Committee, has been delayed, Sen. Durbin blocked action Thursday on the shipping bill.

Unless an agreement can be reached for a vote on the judges quickly, Sen. Durbin was threatening to block any further ''unanimous consent'' requests, which are crucial to Sen. Lott's ability to conduct routine business in the Senate.

Sen. Lott tested Sen. Durbin's resolve by asking unanimous consent for Senate consideration of an amendment proposed by Minority Leader Tom Daschle, D-S.D., to an education bill. Sen. Durbin objected, and Sen. Lott called for a vote to cut off debate on the education bill, effectively making it much tougher for Sen. Daschle to win his amendment. The result puts Sen. Durbin against his own party leader.

The personal and political battle between the senators, which also involves Sen. Phil Gramm, R-Texas, who has been blocking Sen. Durbin's judges, is a potentially beneficial twist for freight consolidators, who have been on the losing end of a compromise deal in the shipping legislation.

The Senate skirmishing buys time for Sen. Slade Gorton, R-Wash., to ''reach out to more Democrats'' for support for a crucial amendment to the Lott bill that would allow non-vessel-operating common carriers to offer shippers volume-discount deals known as service contracts, one lobbyist said.

The issue pits consolidators against dockworker unions that believe consolidators divert business from longshore workers, and vessel operators that face competition from middlemen.

Maritime labor is joined in its opposition to the Gorton amendment by a broad maritime industry group that backs the Lott bill as the best compromise attainable on shipping deregulation. That group includes shipping lines, ports and shippers.

Sen. Gorton says he is only trying to improve the bill. Passage of his amendment, however, might kill the Lott bill by generating labor and carrier opposition. But sources were saying last week that Sen. Gorton had only recruited up to 35 senators for his amendment in the face of vehement AFL-CIO opposition.