To this chapter contents
1. GENERAL INFORMATION
Troubles Diagnosis
A. Engine hard to start or can not be started
Check and adjustment Fault condition Probable causes
Cylinder compression
pressure normal
Loosen carburetor drain bolt to
check if there is gasoline inside
the carburetor
Fuel supplied tom
carburetor sufficient
No fuel is supplied to
carburetor
Remove spark plug, install it
into spark plug cap, and perform
a spark test against engine
round.
Perform cylinder compression
pressure test.
Check if sparks Weak sparks, no spark at
all
Low compression
pressure or no pressure
Re-start by following the starting
procedures
No ignition
There are some signs of
ignition; nut engine can
Remove the spark plug again
and check it.
Remove carburetor after 30
minutes and connect a hose
onto fuel rich circuit. Then blow
the hose with air
Dry spark plug Wet spark plug
Blowing in normal Blowing clogged
No fuel in fuel tank
Check if the pipes, fuel tank to carburetor
and intake vacuum, are clogged.
Float valve clogged
Lines in fuel tank evaporation system
clogged
Malfunction of fuel pump
Loosen or damaged fuel pump vacuum
hose
Fuel filter clogged
Malfunction of spark plug
Spark plug foul
Malfunction of CDI set
Malfunction of AC generator
Ignition coil is in open or short circuit
Ignition coil leads open or short circuit
Malfunction of main switch
Piston ring seized
Malfunction of cylinder valves
Worn cylinder and piston ring
Cylinder gasket leak
Sand hole in compression parts
Malfunction of throttle valve operation
Air sucked into intake manifold
Incorrect ignition timing
Fuel level in carburetor too high
Malfunction of throttle valve operation
Throttle valve opening too wide
Malfunction of automatic by- starter
1-12
To Next Page
Loading...
