Chevrolet 1980 Light Duty Truck Service Manual page 412

6A-8 ENGINE M ECHA NICAL
Condition
Engine Will Not Crank
Engine Cranks Slowly -
Will Not Start
(M inim um Engine
Cranking Speed -
100 RPM)
Engine Cranks Normally -
Will Not Start
Possible Cause
Loose or Corroded
Battery Cables
Discharged Batteries
Starter Inoperative
Battery Cable
Connections Loose or
Corroded
Batteries Undercharged
Wrong Engine Oil
Incorrect Starting
Procedure
Incorrect or
Contam inated Fuel
No Fuel to Nozzles
No Fuel to
Injection Pump
Plugged Fuel Return
System
Fig. 6A-2--Diesel Diagnosis
Correction
Check connections at battery, engine
block and starter solenoid.
Check generator o u tp u t as described in
Section 6D.
Refer to Starter Diagnosis as described
in Section 6D .
Check connections at battery , engine
block and starter.
Check charging system as described in
Section 6D.
Drain and refill with recom m ended oil.
Use recom m ended starting procedure.
Flush fuel system and install correct fuel.
Loosen injection line at a nozzle. Do not
disconnect. Use care to direct fuel away
from sources o f ignition. Wipe connection
to be sure it is dry. Crank 5 seconds. Fuel
should flow from injection line. Tighten
connection. If fuel does not flow, check
fuel solenoid operation as follows:
Connect a 1 2 volt test lam p from wire
at injection pum p solenoid to ground.
Turn ignition to " ON" . Lamp should
light.
If lamp does not light, check wiring to
solenoid.
Remove line at inlet to injection pum p
fuel filter. Connect hose from line to
metal container. Crank engine. If no
fuel is discharged, test the fuel supply
pum p.
If the pum p is OK, check the injection
pum p fuel filter and, if plugged, replace
it.
Disconnect fuel return line at injection
pum p. Connect a hose from the return line
to a metal container. Connect a second
hose to the injection pum p connection;
route it to the m etal container. Crank
the engine; if engine starts and runs,
correct restriction in fuel return system .
LIG H T T R U C K S ER V IC E M AN UAL