Overhauling of the regulator
Regulators older than 266 09 should be replaced or refurbished as they may overload the pump. In the case of GM diaphragm pumps, they can even damage them. In the case of newer regulators, after about 150,000 km, the regulator valve wears out and starts to leak. As a result, the injection system is not able to maintain the correct pressure of 50 bar at idle.
Overhaul consists in replacing the plastic parts with brass ones and replacing the valve seat and the needle with the ball. After overhaul, the regulator works like new and can withstand a similar milage as the new regulator. The housing of the regulator is again galvanized and new O-rings are placed on the regulator.