Troubleshooting; Engine Does Not Start Or Is Hard To Start - Honda MB5 1982 Shop Manual

~HONDA
~
MBS
•.
14. TROUBLESHOOTING
ENGINE DOES NOT START OR IS HARD TO START
ENGINE LACKS POWER
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POOR PERFORMANCE AT LOW AND IDLE SPEEDS
POOR PERFORMANCE AT HIGH SPEED
POOR HANDLING
ENGINE DOES NOT START OR IS HARD TO START
CHECK
1. Check if fuel is reaching carburetor
REACHING CARBURETOR
I
2. Remove spark plug and try spark
test
SPARK JUMPS
j
3. Test cylinder compression by
operating kick pedal
COMPRESSION IS NORMAL
4.
sl
by
follow;ng nonn•l
starting procedure
ENGINE DOES NOT FIRE
+
5. Remove spark plug
DRY
j
6.
Restart with choke applied
Date of Issue: Ju ly, 1981
© HONDA MOTOR CO., LTD.
PROBABLE CAUSE
NOT REACH IN G - - - - - - - - • ( 1 ) No fuel in fuel tank
CARBURETOR (2) Glogged fuel pipe from tank to
carburetor
(3)
Clogged float valve in carbu-
retor
(4)
Breather hole in fuel tank cap
clogged
SPARKS ARE WEAK OR D 0 - - - - - ( 1 ) Faulty spark plug
NOT JUMP AT ALL
(2)
Fouled spark plug
(3)
Foulty CDI unit
(4)
Broken or shorted high
tension cord
(5)
Broken or shorted ignition coil
(6) Faulty ignition switch
LOSS OF COMPRESSION-----•(1) Piston rings stuck in ring lands
(2)
Flaw in casting
(3)
Compression leak past crankcase
(4)
Faulty or clogged reed valve
(5)
Worn cylinder and piston rings
(6)
Blown cylinder head gasket
ENGINE FIRES B U T - - - - - - - ( 1 ) Excessively open choke
STOPS SOON
(2)
Choke stuck closed
(3)
Air leaking past manifold
(4)
Ignition timing out of proper
adjustment
WET - - - - - - - - - - - - (1) Carburetor flooded
159
(2)
Carburetor choke excessively
closed
(3)
Throttle valve excessively
opened
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