Booster pumps have been installed on the stranded container ship Rena and further pumps will be added to accelerate the rate of oil extraction.
However, the pumping of oil from the stricken container ship will not resume until at least this morning, as bad weather continues to thwart recovery efforts.
Drew Shannon, of Svitzer Salvage, said the four salvors on board yesterday were due to come off the ship last night, when swells and wind were forecast to remain strong.
They would return this morning.
Mr Shannon said a large crack in the starboard side had widened over past days but the ship's condition had not significantly deteriorated.
Maritime New Zealand salvage unit manager Andrew Berry yesterday said pumping the oil from the Rena was taking much longer than anticipated but was progressing as fast as possible.
Maritime New Zealand had estimated the oil could be removed within 40 hours. But pumping was yesterday close to the 40-hour mark and only 90 of the 1700 tonnes that were on board had been recovered.
At the current speed, the oil removal would take about 400 hours.
Mr Berry said the removal was proceeding slower than anticipated because of the thick consistency of the oil on board.
National on-scene commander Ian Niblock said a coastal navigation warning had been issued to include the East Cape, following the discovery of the oil-covered remains of containers that washed ashore at Te Kaha and Te Araroa yesterday morning.
The New Zealand Defence Force is standing down some of its operations, as there have been no new spillages of oil or containers. It will remain on standby should the situation change.
Insurers for the vessel have promised to "meet its owner's obligations in full," according to a statement from the ship's owner, Costamare Inc.
Rena is covered by a policy which includes pollution liabilities through international maritime insurer the Swedish Club.
The statement comes as Rena's captain and navigation officer were remanded on bail until November 2 after appearing in court yesterday on charges under section 65 of the Maritime Act for "operating a vessel in a manner causing unnecessary danger or risk".
- Additional reporting APNZ
