Troubleshooting; Engine Does Not Start Or Is Hard To Start - Honda 1988 Z50R Service Manual

15. TROUBLESHOOTING
ENGINE DOES NOT START OR IS HARD TO START 15- 1
ENGINE LACKS POWER 15-2
POOR PERFORMANCE AT LOW AND IDLE SPEEDS 15-3
POOR PERFORMANCE AT HIGH SPEED 15-4
POOR HANDLING 15-4
WEAK OR NO SPARK 15-5
ENGINE DOES NOT START DR IS HARD TO START
CHECK
1. Check if fuel is getting to
carburetor
FUEL TO CARBURETOR
~
2. Try spark test
GOOD SPARK
3 . Test cylinder compressIon
COMPRESSION NORMAL
1
4 . Start by following normal
starting procedure
ENGINE DOES NOT START
1
5. Remove spark plug
DRY
~
6 . Start w ith choke applied
PROBABLE CAUSE
NO FUEL TO----------------- .
• (1)
No fuel in fuel tank
CARBURETOR
121 Clogged fuel lube or fuel filter
131 Clogged float valve
141 Clogged fuel tank cap breather
hole
WEAK OR NO SPARK----------
III
Faulty spark plug
121 Fouled spark plug
131 Faulty ignition control module UeM)
141
Broken or shorted spark plug wire
151
Faulty alternator
161 Broken or shorted ignition coil
(71 Faulty ignition pulse generator
lSI Poorly connected, broken or short-
ed wires
191 Faulty engine stop switch
• (1)
Slow starter cranking speed
1m
121
Valve clearance too small
131 Valve stuck open
lOW COMPRESSION ------------_
1 41 Worn cylinder and piston rings
151 Damaged cylinder head gasket
161 Seized valve
171 Improper valve timing
ENGINE STARTS BUT----------- . • (1) Air leaking past carburetor
SOON STOPS insulator
121 Improper igniton timing (ignition
control module HeM) or ignition
pulse generator faulty)
131 Fuel' air mixture too lean
WET PLUG ----------~ ••
i
1) Carburetor flooded
i21 Fuel/air mixt ure too rich
131 Air cleaner dirt y
15-1