Fuel Pressure Regulator

If fuel pressure gauge is already attached, go to next step. If not, disconnect banjo coupling at inlet to fuel injection manifold. Connect fuel pressure gauge at this point, using existing seals. Ensure pressure gauge hangs vertically.
Connect Pressure Gauge (83 93 514 ), with "Y" connection, to vacuum port of fuel pressure regulator. Hang pressure gauge vertically. Connect cooling system pressure tester to "Y" connection.
Turn ignition off. Remove fuse No. 30 on 900 models. Remove fuses No. 14 and No. 22 from 9000 models. Connect a jumper lead between fuse No. 27, 28, or 29 and slot of fuse No. 30 for 900 models. Connect the jumper between fuse No. 22 and slot of fuse No. 14 on 9000 models. This will provide current to fuel pump. Turn ignition on.
Fuel pressure should increase to approximately 36 psi (2.5 kg/cm² ). Using a cooling system pressure tester, increase system pressure as specified in APPLIED PRESSURE REGULATOR SPECIFICATIONS table, and compare fuel pressure to specification.
Remove cooling system pressure tester. Install vacuum pump to "Y" connection. Fuel pressure should be approximately 36 psi (2.5 kg/cm² ). Use vacuum pump to reduce system pressures as specified in APPLIED VACUUM REGULATOR SPECIFICATIONS table, and compare fuel pressure to specification. Disconnect vacuum pump.
Turn ignition on to operate fuel pump. Verify fuel pressure of 36 psi (2.5 kg/cm² ). Turn ignition off. Pressure should drop 1.4-2.8 psi (.1-.2 kg/cm² ), and then hold steady for at least 10 minutes.

If pressure drops more than specified, check for leakage in pressure regulator and fuel pump non-return valve.

APPLIED PRESSURE REGULATOR SPECIFICATIONS

Applied Pressure psi (kg/cm² )	Fuel Pressure psi (kg/cm² )
0 (0)	36.3 (2.5)
2.9 (.2)	39.2 (2.7)
5.8 (.4)	42.1 (2.9)
8.6 (.6)	44.9 (3.1)

APPLIED VACUUM REGULATOR SPECIFICATIONS

Applied Vacuum In. Hg	Fuel Pressure psi (kg/cm² )
0	36.3 (2.5)
5	33.4 (2.3)
11	30.5 (2.1)
16	27.5 (1.9)