Table 5-2. Direct Support Troubleshooting - Continued
TEST OR INSPECTION
ENGINE - Continued
HARD TO START/STALLS AT IDLE SPEED/DOES NOT RUN SMOOTHLY - Continued
Step 2. Check for misfiring cylinders. Start engine. Hold injector follower down with a screwdriver to
prevent operation of injector. If cylinder has been firing properly, cylinder will miss with a
noticeable change in sound and engine operation. If cylinder has been misfiring, there will be
no noticeable change. Check all cylinders and tag misfiring injectors.
Remove tagged injectors (see para 6-43).
Test and repair injectors (see para 6-43).
Step 3. Repeat check for misfiring cylinder(s).
If cylinder(s) still misfire, perform engine tune-up.
Step 4. Check engine compression. lf minimum compression is not 450 psi (3101 kPa) at 600 rpm,
500 ft above sea level, remove air box covers (see para 6-11.). Variation between cylinders
must not exceed 25 psi (172 kPa). Inspect compression rings through ports of cylinder liners.
Replace damaged or broken compression rings (see para 6-33).
FAILS TO DEVELOP FULL POWER
Step 1. Perform engine tune-up.
Step 2. Check exhaust manifold for leaks.
Tighten loose connections (see para 5-24).
Replace damaged exhaust manifold gaskets (see para 5-24).
Replace damaged exhaust manifolds (see para 5-24).
Step 3. Check if cylinder liner ports are clogged. Remove air box covers (see para 6-11).
Check and clean cylinder ports if clogged (see para 6-32).
Step 4. Inspect turbocharger for free movement.
Replace or repair defective turbocharger (see para 5-23).
Step 5. Check operation of electronic engine control.
Repair or replace electronic engine control (see para 5-28 and 6-28).