Table 4-2. Unit Troubleshooting - Continued
TEST OR INSPECTION
ENGINE - Continued
ENGINE CRANKS BUT WILL NOT START
Step 1. Air in fuel system.
Prime the system by blocking or disconnecting the supply line from the fuel pump, the apply
fuel under pressure (60-80 psi) to the inlet of the secondary fuel filter. Purge the system of air
by allowing fuel to flow freely from the fuel return line until a solid stream without air bubbles is
Step 2. Check for choked fuel filter.
Replace fuel filter (see para 4-130).
Step 3. Check for blocked or broken fuel line.
Replace (see para 4-130 and 4-167).
Step 4. Remove fuel tank fill cap. If engine runs smoothly, tank vent is blocked.
ENGINE HAS DIFFICULTY IN STARTING
Step 1. Check battery and starting motor connections.
Clean and tighten connections.
Step 2. Check engine oil level.
Fill engine with correct lubricating oil (see Chapter 3, Lubrication Instructions).
Step 3. Check starter motor current draw.
Repair motor as required (notify Direct Support).
ENGINE STARTS BUT STOPS OR RUNS ERRATICALLY
Step 1. Check for fuel leaks.
a. Tighten/remake connections.
b. Replace fuel lines (see para 4-130 and 4-167).
Step 2. Check for crimped or blocked fuel lines.
Replace fuel lines (see para 4-130 and 4-167).