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Home >> GMC >> 1987 >> Forward Control 6.2 J, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 32 (Engine Controls - Remove/Install/Overhaul) >> Fuel System (Diesel) >> Purging Fuel System
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Purging Fuel System

WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 1994 GMC Vandura Special, 1994 GMC Vandura, 1994 GMC Rally Camper Special, 1994 GMC Rally, and 1994 GMC Forward Control. However, it is still accessible from the selected car via links, so may be relevant.
  1. Park vehicle on a level surface. Place drain pan under drain hose to collect fuel. Open drain valve 3-4 turns. With fuel tank cap installed, use air nozzle and apply 3-5 psi (.21-.35 kg/cm2 ) through fuel return hose at injection pump.
  2. Contaminated fuel will be forced out of tank via filter drain hose. Continue to drain fuel until clear fuel is observed. Entire fuel tank may have to be drained. Close drain valve. Install fuel return hose.
NOTE: If vehicle is equipped with dual tanks, perform purging procedure on each tank.