The work likely will cost around $4.6 million and include replacing the gasoline engines with diesel ones on the army's dozen in-service Scorpions, Philippine army spokesman Col. Antonio Parlade said.
Six more Scorpions, mothballed because of the scarcity of spare gasoline engine parts, also will get diesel engines to bring the vehicles back into service, he said.
A project management team was formed last week, "so it will be 18 (upgraded tanks) for the same budget," he said. "These are important, especially in our (operations) in central Mindanao" against insurgents, Parlade said.
The eight-ton FV101 Scorpion, an armored reconnaissance vehicle or light tank, was manufactured by Alvis in the United Kingdom. It was introduced into service with the British army in 1973 and served until 1994. More than 3,000 were produced.
The original engine for the Scorpion was the Jaguar J60 4.2 liter gasoline engine, which was replaced in later models by a Cummins or Perkins diesel engine.
Maximum speed is about 50 mph and a Scorpion can accelerate from zero to 30 mph in 16 seconds. The maximum speed on water, with the flotation screen deployed, is just under 4 mph.
The Scorpion 90, or Scorpion 2 version -- some of which the Philippines purchased -- was armed with the long-barreled Cockerill Mk3 M-A1 90mm gun and designed for the export market.
The Philippine army's light armor division also maintains V-150S and Simba armored infantry fighting vehicles.
The Simba wheeled armored personnel carrier was designed by GKN Sangkey, now part of BAE Systems Land and Armaments. The Philippine army ordered 150 Simbas, of which the majority were assembled in the Philippines from kits provided by GKN.
Over the years the Philippines also bought around 150 of the V-150S 4X4 light amphibious armored cars made since the 1960s by the Terra-Space division of the Cadillac Gage company in the United States.
In December 2006 the first Philippines upgraded marine corps V-150 rolled out of the Cummins Philippines plant south of Manila. The upgrade included replacement of the engines with Cummins 6CTA 8.3 turbocharged diesels for greater power and commonality with the V-150S 6X6 variant, called the LAV-300, operated by the marines.
Old V-150 engines rendered surplus by the upgrade were refurbished and used to revive derelict armored vehicles, including Chaimites, built by Portuguese company Bravia and purchased by the Philippines in the 1970s.
The Portuguese army is gradually phasing out its Chaimites in favor of the Austrian Pandur II 8X8 armored personnel carrier.