Troubleshooting Guide; Troubleshooting And Correction - Hitachi CS 51EAP Service Manual

1. Troubleshooting and correction

Trouble
The crank shaft does
Starter
not rotate.
handle
cannot be
pulled.
The recoil starter does
not rotate.
No compression
Short-circuited due to foreign matter between the spark plug
electrodes.
No spark
Startup is
impossible.
The spark plug does
not become wet with
fuel after repeated
starting operation.
The spark plug is wet
due to excessive fuel
supplied.
Weak spark
Idling stops
although
Low compression
startup is
possible.
Good spark and
compression

TROUBLESHOOTING GUIDE

Faulty piston ring
Seized piston and cylinder
Faulty crank shaft bearings
Magneto rotor contact with
ignition coil
Broken recoil starter
Faulty starter pawl
Faulty piston ring
Worn piston
Expired oil seal service life
Worn cylinder
Defective sealing of the packing
Faulty decompression valve
Stop switch not at startup position
Dirty or faulty spark plug
Improperly connected plug cap
Disconnected or improperly
connected high voltage cord
Ground connection of high
voltage cord
Disconnected or faulty ignition
coil ass'y
Large gap between the magneto
rotor circumference and ignition
coil ass'y
No fuel in the fuel tank
Clogged fuel filter
Faulty fuel pipe
Faulty vent hole (inner cap) on
the fuel tank
Faulty carburetor ass'y
Starter handle pulled repeatedly
with choke button pulled out (set
at "startup")
Dirty or faulty spark plug
Improper air gap
Worn piston ring
Expired oil seal service life
Faulty decompression valve
Revolutions too low for idling
Poorly adjusted carburetor ass'y
Cause
-1-
Corrective action
Disassembly and parts
replacement
Inspection and replacement
Parts replacement
Cleaning or replacement
Removal of foreign matter: In
case of frequent occurrence,
disassemble and clean the
engine.
Adjust to startup position.
Cleaning or replacement
Inspection and replacement
Repair or replacement
Repair
Replacement
Adjustment
Add properly mixed fuel
(25:1 to 50:1).
Cleaning or replacement
Adjustment, replacement or
connection
Replacement
Adjustment, cleaning or
replacement
Dry the spark plug.
Remove excessive fuel.
Cleaning or replacement
Adjustment
Replacement
Cleaning or replacement
Adjustment