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 cylin er 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 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).