3500 4x4 Pickup L6-359 5.9L DSL Turbo (1996)
Injection Timing: Technical Service Bulletins
Engine - Hard Starting Diagnosis
NO: 18-06-98
GROUP: Vehicle Performance
DATE: Feb. 27, 1998
SUBJECT:
Hard Starting Diagnosis
MODELS:
1994 - 1998 (BRIBE) Ram Truck
NOTE:
THIS INFORMATION APPLIES TO THE 5.9L CUMMINS MECHANICALLY INJECTED 12 VALVE DIESEL
DISCUSSION:
Hard or no start complaints can be caused by many conditions. The following points will help in diagnosing hard start concerns.
1.
Low fuel pressure or air entering the fuel system.
This can cause a low rpm miss/instability, white smoke, hard starting, or low power. Basic fuel system diagnostics should be followed. Technical
Service Bulletin 14-07-96 should be referenced when diagnosing fuel concerns.
2.
Loss of fuel system prime.
A leak in the return portion of the fuel system can allow air to enter the injection pump eventually. An area to inspect is the 5/16 inch rubber hose
that connects to a steel line on the back of the injection pump. Replace the line if leaking is found or suspected.
3.
Incorrect starting procedures.
In ambient temperatures below 15 C (60 F), the throttle should be partially repressed after engaging the starter. If the engine will not start, full
throttle should be applied. Hard starting in temperatures above 15 C (60 F) can be affected by too low an idle speed. Lower idle speeds increase
the need to depress the throttle to start the engine.
NOTE:
DO NOT EXCEED A MAXIMUM CRANKING TIME OF 30 SECONDS AT A TIME WHEN HARD STARTING IS EXPERIENCED.
4.
Injection pump timing.
Retarded (late) injection pump timing affects starting and excessive white smoke in ambient temperatures of -6 C (20 F) or below. See the chart for
a list of all injection pump timing specifications.
