TRUCK SERVICE MANUAL
To check valve opening pressure, gradually
at by-pass opening or closing to differ depending upon
close rail flow valve to increase rail pressure.
whether air pressure is increasing or decreasing.
7. Watch rail pressure gauge and fuel discharge from
aneroid line. When starting check valve opens, a significant
A. If air actuation pressure is to high, screw two piece shaft
flow increase will occur. Fig. 524
1/4 turn, remove aneroid shims, Part No. 144921, or add a
8. Check for any tendency of aneroid starting valve to
washer, Part No. 67684 as shown in assembly drawing. If air'
stick by repeatedly opening and closing of rail flow valve.
actuation pressure is too low, add shims or lengthen shaft. If
See Table 523 for starting check valve spring opening
capscrew securing shaft to bellows is removed, retorque 20 to
25 in. lbs. (2.3 to 2.8 Nm) B. The proper aneroid spring
must be employed as specified. Table 522.
Table 5-2-3: Starting Check Valve Spring Specifications
Table 5-2-2: Aneroid Bellows Spring Specifications
Lb. @ In
Code Coils In [mm]
[mm] [kg @ mm]
Factory Aneroid Settings, AR And Code
Checking Starting Check Valve
(Ref. Table 5-2-1)
1. To check aneroid starting check valve action, stop
Aneroid Assembly Number And Code
fuel pump test stand and set air regulator to 0 inches of
mercury. Disconnect aneroid fuel return line at fuel pump and
1. The 40000 series AR numbers identify the aneroid air
plug opening In gear pump inlet suction fitting.
2. Move aneroid supply line from bottom of housing to
2. The last two numbers of the AR Is the aneroid air
fuel pressure check point on shutdown valve. Plug hole In
bottom of housing.
Note: The current check valve, Part no 216737, Is not
in the field If engine is on an engine dynamometer
interchangeable with the older style check valves.
A. Air actuation pressure is set by manometer on a fuel
3. Open rail flow valve on test stand completely, open
pump test stand to the value indicated under "Bellows Air
rail flow snubber valve and hold pump throttle wide open.
Actuation Pressure" In table.
4. Start test stand at lowest possible speed setting, rail
B. The bottom screw (fuel pressure) setting is made at
pressure must be less than 10 psi (69 kPa).
engine test so that engine develops power indicated under
setting "BHP @ Speed" in Table 521. Remove air line from air
5. Observe fuel discharge from aneroid hose. There
should be only a slight dribble of fuel which Is leakage. If
valve is stuck open, free flow of fuel will occur.
Note: The above procedure can and should be employed In
the field, If engine is on an engine dynamometer
4. All aneroids shipped as service parts will be set and
ready for engine installation.
Fuel hose size - No. 5 on all engine models
Line connection points'
Standard Automotive PT (type G) and VS. See Fig.
Fig 5-2-4, F5288 Checking starting check valve,