System (Line) Pressure Test

NOTE: Connect and bleed pressure gauge and valve in same manner as for Control Pressure Test. Keep fuel pump relay bridged. Be sure electrical plugs are connected to control pressure regulator and auxiliary air regulator.

Ensure electric fuel pump activates when ignition switch is turned ON and that fuel filter is clean.
CLOSE valve (Fig. 3 ). Start engine and run at idle.
System (line) pressure should be 64-74 psi (4.5-5.2 kg/cm² ). If not within specifications, clean, check and adjust fuel distributor pressure regulator (relief) valve.

Fig 1: Components of Pressure Regulator Valve
Courtesy of NOT AVAILABLE
System pressure may be adjusted by adding to or removing shims from valve. See Fig 1. Pressure will be changed 1 psi (.06 kg/cm² ) by a 0.004" (0.1 mm) shim or 4 psi (.3 kg/cm² ) by a 0.020" (0.5 mm) shim.
If system pressure is low, check for leaks between fuel pump and control pressure regulator. Also check for defective fuel pump.