TM 5-3740-218-13&P
Table 4-2. Unit Troubleshooting
Malfunction
Test or Inspection
Corrective Action
ENGINE AND PUMP ASSEMBLY
1. ENGINE FAILS TO START.
Step 1.
Check for partially discharged battery.
Replace (para 4-31).
Step 2.
Check electrical system wiring.
Check electrical system for tight connections and frayed or
defective wiring. Tighten loose connectors. If wiring is
defective, replace as required (para 4-37).
Step 3.
Check for defective key switchbox.
Check fuse and replace if blown.
Check for disconnected wires behind key switchbox.
Check oil level switch:
Check continuity between oil level switch yellow and green
leads. If there is continuity, oil level switch is faulty. Replace
engine (para 4-19).
If no continuity between yellow and green leads, check
ignition system.
Check that battery cables are securely connected and free of
corrosion. Tighten or clean cables (para 1-16) or replace
cables (para 4-31).
Step 4.
Test ignition system.
Test spark plug:
Remove spark plug, attach it to spark plug cap, and ground
side electrode against cylinder head cover. Turn on engine
switch, pull recoil starter, and check to see if sparks jump
across electrodes.
If no spark, set gap on new spark plug to 0.039 in. Attach
spark plug cap to new spark plug and recheck. If spark is
present, install new spark plug.
If no spark is present, disconnect wire A2 from engine switch
and check for spark. If spark is present, replace engine
switch.
If still no sparks, replace engine (para 4-19).
