TRUCK SERVICE MANUAL
FUEL SYSTEM
Check 2 - Fuel Pressure Regulator
Correction
Clean and/or replace regulator as required to maintain
pressure at 120 psi [827 kPa] .
Cause
Change plumbing to the right size and length.
Regulator sticking. (Indicated fuel pressure erratic.)
Correction
Regulator not plumbed into the fuel circuit per conversion
instructions.
Change gear pump as required. (For gear pump delivery
specifications and gear pump checking procedure see
Check 3 - Gear Pump
Complaint No. 6.)
Cause
ST-790 TEST STAND HYDRAULIC SYSTEM LEGEND
1. Air Regulator and Filter
20.
Pressure Regulator
Pressure regulator is operating properly but pressure in
2. Filter Drain
21.
Dampening Valve
excess of 120 psi [827 kPa] cannot be obtained with an
3. Air Valve
22.
Fuel Pressure Gauge
NHRS injector installed.
4. Hydraulic Reservoir
23.
Injector Seat Assembly
5. Air Pressure Gauge
24.
Restrictor Orifice
6. Hydraulic Oil Level Gauge
25.
Check Ball
7. Sight Glass
26.
Spring
8. Hydraulic Lock Up Valve
27.
Solenoid Valve
9. Hydraulic Loading Cylinder
28.
Vials
10, Piston
29.
O-Ring (Goshen Part No.
GRG-27-12)
11.
Piston Rod
(Parker Part No. 2-114)(Lincar Part
12.
Piston Return Spring
No. 11-114)
13.
Cylinder Breather
30. .035 Orifice
14.
Bleed Plug
31. Secondary Check Valve
15.
Fuel Tank
32. Filter Drain Cock
16.
Fuel Strainer
17.
Gear Pump
18.
Fuel Filter (Part No. 105204)
19.
Injector Inlet Connector
A. Air In.
B. Hydraulic Fluid
C. Fuel From Tank To Pump
D. Fuel From Pump To Filter Inlet (Stratoflex #213 M.H.P. #4 21"
Length)
E. Fuel From Injector Inlet To Pressure Regulator (Stratoflex #213
M.l.P.
'4 21 Length)
F. Fuel From Pressure Regulator To Pressure Gauge (3/16 X 18"
Copper Tubing)
G. By-Pass Fuel From Pressure Regulator (3/16 I.D. X 3/8 O.D. X 9
1/2" Long
Clear Vinyl Tubing)
H. Metered Fuel To Vials (3/16 I1.D. X 3/8 O.D. X 46" Long Clear
Vinyl Tubing)
I. By-Pass Fuel From Solenoid Valve (3/16 I.D. X 3/8 O.D. X 7" Long
Clear
Vinyl Tubing)
J. Drain Fuel (5/16 I.D. X 1/2 0.D. X 14" Long Clear Vinyl Tubing)
K. Injector Return Fuel (5/16 I.D. X 1/2 O.D. X 22" Long Clear Vinyl
Fig. 6-1-121, Test stand hydraulic system
Tubing)
L. Fuel From Filter Outlet To Injector Inlet Connector (Stratoflex -213
M.II.P.
04 37 1/2" Length)
M. Fuel From Solenoid To Vial (1/8 X 2 1/4" Long Copper Tubing)
X. Original Plumbing (Omit)
484
