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i) Measure the resistance between each three of the connectors, which were disconnected in the above
process.
ii) In case the average of the phase-to phase resistance measured is 65mΩ±5mΩ, and the deviation is 10mΩ
or more, replace the generator.
iii) Connect the cables of the generator after inspection or replacement.
(4) Inspection of the ignitor
Generally, spark ignition is more difficult in a combustion chamber of an engine, where fuel mixture is
compressed, than under atmospheric pressure. The discharge distance (the spark plug gap) is 0.4 – 0.5mm
in the engine, which is equivalent to the discharge distance of 5-6mm under atmospheric pressure. So make
a spark plug for spark check under atmospheric pressure as shown below, whose discharge distance is more
than 5mm.
①
How to make a special spark plug for spark check
i)
Get CM-6 ready. It doesn’t have to be a new one but a used one.
ii)
Cut off a part of the spark plug body as shown in the picture.
②
Detach the both plug caps and remove the spark plugs.
③
Attach the special spark plug mentioned in
①
to the plug cap.
④
Turn on the starter and check if there is a spark between the center electrode and the spark plug body,
which is cut short as shown in Fig. 6. Replace the ignitor if there is no spark.
。
Note: The spark check inspection should be done to both ignitors, right and left.
WARNING
Inspect the ignitors in well ventilated room away from any source of fire to avoid fire accidents.
7.
INSPECTION AFTER EVERY 100 HOURS OF OPERATING TIME
The engine needs to be dismounted and disassembled for maintenance. Contact us if you need us to inspect it.
(1) Disassembling the engine for inspection and replacement
①
Inspection and maintenance of the cylinder blocks
i) Remove the spark plug and the four cap screws M4 x 15 from the cylinder block and detach it from the
engine. Replace the gasket whenever you detach the cylinder block.
ii) Wash the cylinder block with gasoline.
Summary of Contents for GT120THU
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