WELLINGTON, New Zealand (AP) _ Officials investigating the sinking of the Soviet cruise liner Mikhail Lermontov Wednesday ordered an inspection of the ship's safety and rescue gear following allegations that the lifeboats had rotted.

The 20,000-ton vessel sank in about 100 feet of water Sunday night about two hours after striking a reef in New Zealand's Cook Strait. Rescuers saved all 409 passengers, mostly Australians, and all but one of the 339 Soviet crewmen.

A 34-year-old Soviet engineer is believed to have drowned when rocks tore a 33-by-10-foot gash in the ship's hull.

The Transport Ministry, which launched a preliminary inquiry on Tuesday, said officers would carry out inspections of the vessel's life boats and other emergency equipment picked up after the sinking.

The order was given following a New Zealand naval officer's claim that the liner's lifeboats had rotted and that other safety equipment was in a poor state of repair.

Lt. Peter Batcheler, who commanded a navy patrol boat which assisted with the rescue operation, was quoted by a Wellington newspaper Tuesday as saying that the ship's safety equipment was ''dangerously faulty.''

''If it (the sinking) was out at sea they would not have got back alive with that equipment. I am quite convinced of that,'' he said.

The ship's master, Capt. Vladislav Vorobyev, stood before the inquiry again Wednesday after having refused earlier to hand over the ship's log and other relevant documents.

Capt. Steve Ponsford, head of the inquiry, questioned the Soviet skipper for more than five hours Tuesday. He said the Soviet captain answered questions ''clearly and straightforwardly'' and that no questions had gone unanswered.

Ponsford said he requested through the Soviet Embassy that Vorobyev hand over charts being used when the vessel was making its way through Cook Strait, as well as bridge and engine room logs, details of the ship's specifications and other documents.

Vorobyev has suggested that map errors and a New Zealand pilot were to blame for the accident, but New Zealand officials say the Soviet captain was at the helm at the time and there was nothing wrong with the charts.

The pilot, Capt. Don Jamison, will also appear before the inquiry, Ponsford said.

The inquiry is to establish the main reason for the sinking and recommend to Transport Minister Richard Prebble whether a full inquiry is needed. Ponsford said he hoped to complete the inquiry during the weekend and have a report to Prebble by the end of next week.

The New Zealand government has told Vorobyev and senior officers of the Mikhail Lermontov to remain here until the inquiry is complete.

Meanwhile, the Soviet Embassy, upset at continuing media criticism of the crew's handling of the evacuation, issued a statement late Tuesday saying the crew and New Zealand rescuers ''succeeded in preventing a terrible catastrophe.

''We are disappointed that certain circles appear to attempt to use this accident in order to distort the actions of Soviet crew members,'' the statement said.

Residents who assisted in the rescue dismissed reports that the crew were unhelpful during the evacuation and claims that the Soviets collected their own gear together and looked after themselves before the passengers.

Farmers Tony and David Baker and fisherman Dave Fishburn said the Soviet crewmen did ''everything humanly possible'' to assist throughout the evacuation of the ship.

''The Russians did a magnificent job evacuating the ship. No passenger was left unattended and the Russians also assisted the local boaties in handling, loading and unloading their vessels,'' they said.

Australian survivors, interviewed upon their return home, generally agreed that the Soviet crew members made extraordinary efforts to get them off the vessel amid the confusion.

The Transport Ministry's chief surveyor of ships, Jack Critchley, agreed. ''It was a brilliant exhibition of rescuing,'' he said in telephone interview with The Associated Press from Sydney, Australia.

''You had 300 odd passengers and a big percentage of them were very elderly. The only fatality was a Russian crew member. You can't say the passengers got off by themselves. I think the operation speaks for itself.''