Motive Power Industry BLUR 150, Service Manual

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(4) Trouble of cold start
General trouble location: 1. Water in fuel; 2. Fuel pump; 3. Engine temperature sensor; 4. Nozzle; 5.
Ignition coils; 6. Air throttle and & idle air bypass; 7. Engine mechanism.
Procedure for general diagnoses:
No. Operating Procedure
Detection
Results
Subsequent Steps
Yes Next step
1
Connect a fuel pressure gauge before the fuel inlet of the
nozzle; start the engine to check the fuel pressure at 300kPa
or so.
No Repair the fuel system.
Yes Next step
2
Disconnect the ignition cable and connect a spark tester;
start the engine and check any high-voltage flash
(blue/white).
No Repair the ignition system.
Yes
Correct circuits or replace
any sensor.
3
Press the engine temperature sensor connector and start the
engine; check if the engine successfully started. (Or
install
a series-connected resistor (2500 Ω ) in lieu of the engine
temperature sensor at the engine temperature sensor
connector.
Observe if the engine is successfully started.)
No Next step
Yes
Clean the air throttle and
the idle air bypass.
4
Slightly pull the throttle to check if the engine is easily
started.
No Next step
Yes
Replace the defective
nozzle.
5
Disassemble the nozzle and check any leakage or jam in
the nozzle with a nozzle cleaner & analyzer.
No Next step
Yes Change fuel.
6
Check fuel and observe any trouble attributed to fuel just
added.
No Next step
Yes
Eliminate any mechanical
trouble of the engine.
7
Check pressure of the engine cylinder and find any
possibility of pressure insufficient.
No Next step
Yes Diagnosis assist
8
Connect an EMS adapter and press the power switch to
check voltages at Pins
1#, 19#, and 29#
; check grounding
at Pins
8#
﹐
35
#
and
36#.
No Repair the relevant circuits.
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