GIGLIO ISLAND, Italy — Using a vast system of steel cables and pulleys, maritime engineers Monday gingerly winched the massive hull of the Costa Concordia off the Italian reef the cruise ship had struck in January 2012.

But progress in pulling the heavily listing luxury liner to an upright position was going much slower than expected. Delays meant the delicate operation — originally scheduled from dawn to dusk Monday — was not expected to be completed before Tuesday morning.

“Things are going like they should, but on a timetable that is dragging out,” Franco Gabrielli, head of Italy’s Civil Protection Agency, said Monday evening.

Never before has such an enormous cruise ship been righted. Salvage workers struggled to overcome obstacle after obstacle as they slowly inched toward their goal of raising the crippled ship 65 degrees to the upright position.

An early morning storm delayed the salvage command barge from getting into place for several hours. Later, some of the cables dragging the ship’s hull upright went slack, forcing engineers to climb the hull to fix them.

The Concordia itself didn’t budge for the first three hours after the operation began, engineer Sergio Girotto told reporters.

The initial operation to lift the ship moved it just 3 degrees toward vertical. After 10 hours, the crippled ship had edged upward by just under 13 degrees, a fraction of what had been expected.

Still, the top engineers were staying positive.

“Even if it’s 15 to 18 hours, we’re OK with that. We are happy with the way things are going,” Girotto said.

After some 6,000 tons of force were applied — using a complex system of pulleys and counterweights — Girotto said “we saw the detachment” of the ship’s hull from the reef thanks to undersea cameras.

At the waterline, a few feet of slime-covered ship that had been underwater slowly became visible.

Thirty-two people died on Jan. 13, 2012, when the Concordia slammed into a reef and toppled half-submerged on its side after coming too close to Giglio Island. The reef sliced a 70-meter-long (230-foot) gash into what is now the exposed side off the hull, letting seawater rush in.

The resulting tilt was so drastic that many lifeboats couldn’t be launched. Dozens of the 4,200 passengers and crew were plucked to safety by helicopters or jumped into the sea and swam to shore. The bodies of many of the dead were retrieved inside the ship.

Girotto said the cameras Monday did not immediately reveal any sign of the two bodies that were never recovered.

Costa Crociere S.p.A., the Italian unit of Miami-based Carnival Corp., is picking up the tab for the operation, which it estimates so far at 600 million euros, or $800 million. Much of that will be passed onto its insurers.

Kevin Rebello, whose brother Russel was a waiter on the ship and was never found, said he was in constant touch with the project managers as he monitored news reports.

“I haven’t slept since yesterday,” he told The Associated Press in an interview in Rome. “It’s taken 20 months. If it takes another 20 hours, for me it’s worth the wait.”

Rebello plans to travel to Giglio Island on Tuesday, even though he knows there’s no certainty his brother’s remains will be found. His hope is that someday he can bring his brother home to Mumbai “to give him a decent burial.

“That’s what me, my family, his wife and all of us are hoping for,” he said.

The Concordia’s captain is on trial for alleged manslaughter, causing a shipwreck and abandoning the ship during the chaotic and delayed evacuation. Capt. Francesco Schettino claims the reef wasn’t on the nautical charts for the liner’s weeklong Mediterranean cruise.