Chapter Vi Troubles & Troubleshooting; Engine Does Not Start - FAW Jiefang Automotive 485 Operation & Maintenance Manual

Chapter VI Troubles & Troubleshooting
Trouble causes
1. Low starting speed
(1) Battery runs low, or connecting terminals
are loosened.
(2) Starting motor's carbon brush contacts
poorly with commutator.
(3) Starting motor's gearwheel cannot nest the
gear ring of flywheel.
2. Abnormal fuel system
(1) No fuel oil in the fuel tank, or valve of the
tank not open.
(2) Air in fuel system; water in diesel oil; oil
leaks at joints.
(3) Fuel passage clogged.
(4) Fuel-transfer pump does not supply fuel.
(5) Fuel injector injects no or little fuel; too-low
pressure and poor atomization; fuel injector
pressure-adjusting
injection-hole is clogged.
(6) Fuel-injection pump fuel-discharge valve
leaks fuel; spring is broken; plunger couple is
worn off.
3. Insufficient compression pressure
(1) Valve clearance too big
(2) Valve leaks
(3) Cylinder cover gasket leaks
(4) Piston ring worn off, stuck; opening
overlapped
4. Other causes
(1) Air temperature too low; oil viscosity too
big
(2) Water in combustion chamber or cylinder
I. Engine does not start
spring is broken;
Remedial methods
(1) Recharge it: tighten the terminals; repair
wire-post if necessary.
(2) Repair or replace the carbon brush.
(3) Turn the flywheel to another position. If
necessary, inspect the installation of starting
motor, and eliminate the non-parallelism
between the axes of starting motor and gear
ring.
(1) Fill it; or open the valve.
(2) Remove the air; change the oil; tighten
the joints.
(3) Clean the passage, replace element of
diesel oil filter, and clean fuel-in pipe of
fuel-transfer pump.
(4) Inspect if any air leakage on fuel-in pipe.
Inspect and repair fuel-transfer pump.
(5) Dismantle the fuel injector and adjust it
on its tester, and inspect if fuel-injection
pump starting has more concentricity.
(6) Grinding it: repair or replace parts.
(1) Adjust it as per requirement
(2) Grind the valve
(3) Replace the cylinder cover gasket, and
tighten the bolts on cylinder cover.
(4) Replace it, clean it, adjust it
(1) Put some water into the cooling system.
Start after pre-heating. Use engine-oil with
brand specified.
(2) Inspect, repair or replace it
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