Troubleshooting; Starting Difficulties - Robin EC12 Service Manual

12. TROUBLESHOOTING
For a gasoline engine to start and run satisfactorily, the following three requirements must be met:
2) Appropriate compression in the cylinder.
3) Good spark at correct time to
ignite
the mixture.
If all the three requirements are not met simultaneously, an engine
cannot
be started. There are also other
factors such as
heavy
load at starting or too long an exhaust pipe
causing
a high
back pressure,
which
contribute to hard starting.
The most common causes of engine
troubles are given below.
1)
A proper fuel-air mixture
is supplied to the combustion chamber.
12-1 STARTING DIFFICULTIES
Cause
Defects in spark plug
Defects in high-tension
cord
Defects in magneto
Other defects in electric
system
Gas l e a k through head
gasket or other pans
Defects in piston
assembly
Defects in fuel tank
system
Defects in carburetor
Remedy
1)
If contaminated, wash in gasoline,
2) If spark plug is broken or lost insulation,
3)
Adjust spark gap to.025 (.65mm)
remove foreign matters and dry.
replace plug.
If cord is burnt or damaged, replace
the
ignition coil unit.
1)
If
wire
or insulation is broken, replace
magneto.
2) If magnetism
is
weak, re-magnetize (at
the magneto maker) or replace flywheel.
1)
If switch is faulty (short circuit), replace or
2) If primary wire is grounded to the engine
repair.
body, insulate it with insulating tape.
1) If head gasket is defective, replace.
2) ff head bolts are loose, tighten.
3) If spark plug is loose, tighten.
4)
If spark plug
is
defective, replace.
1) If piston is wom,replace.
2) If cylinder is worn, rebore and use oversize
piston and piston ring.
3 ) If piston rings are worn, replace.
4)
tf piston rings are stuck,clean or replace
rings.
1)
Clean clogged tank outlet.
2)
Clean clogged fuel strainer.
3)
If incorrect fuel is poured into tank or
water is mixed,. drain tank completely and
fill
it with correct fuel.
4)
When fuel pipe i s locked
with
air,
discharge air.
'
1)
If clogged with dust,clean.
2)
If defective, replace.
Clean jets and other orifices, if'they are
clogged.
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Preventive measure
1)
Use spark plugs of specified heat range.
Do not use poor grade oil. C l e a n air
cleaner and avoid dust entry.
2) Do not hit or bend the center electrode
of the spark plug at adjusting or the
insulator may get damaged.
1
) Keep air cleaner always clean.
2)
Do not use poor grade oil.
1)
Be sure to use a fitter when adding fuel.
2)
Use mixture (gasoline 25 to 50:
1)
as
fuel.