Yanmar 3YM30, Service Manual

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3.
Tr
ou
bleshooting
56
TROUBLE AND TROUBLESHOOTING
Cause and Ef
fect
Countermeasure
(V-1) Replace plunger and barrel as a unit.
(V-2) Replace.
(V-3) Disassemble and repair or replace.
(V-4) Lap valves.
(V-5) Bleed air.
(V-6) Replace. (VI-1) Adjust.
(VI-2) Tighten firmly.
(VI-3) Replace.
(VI-4) Bleed air. (VII-1) Lap valves.
(VII-2) Adjust .
(VII-3) (VII-4) (VII-5) Replace.
(VII-6) Disassemble and
repair or replace.
(VII-7) Tighten tightening
nuts uniformly.
(VII-8) Replace. (VII-1) Replace.
(VII-2) Adjust .
(VII-3) Move governor handle to acceleration position.
(VII-4) Check and repair.
(VII-5) Clean.
Countermeasure
TROUBLE WITH STARTING
Chart 7
(I-1) Tighten.
(I-2) Repair using sandpaper or replace.
(I-3) Replace.
(I-4) Repair using sandpaper and
then grease.
(I-5) Adjust.
(I-6) Adjust.
(I-7) Replace. (III-1) Prime well.
(III-2) Adjust.
(III-3) Clean out matter causing clogging.
(III-4) Add fuel to fuel tank.
(III-5) Open cock.
(III-6) Clean.
(III-7) Disassemble and repair or replace.
(III-8) Drain water from fuel system
and prime. (IV-1) Lap.
(IV-2) Lap.
(IV-3) Replace.
(IV-4) Clean or replace.
(IV-5) Adjust.
(1) Loose battery engage
magnet terminal
(2) Faulty connection
in starting switch
(3) Cut battery engage
magnet coil
(4) Rough cap movement
(5) Edges of gear
teeth misshapen
(5) Cut starter coil
(6) Worn commutator
(7) Slippage of starter clutch
(9) Insufficient battery charge
(8) Excessive resistance
between battery and starter
(6) Faulty positioning of
pinion and ring gears
(7) Seizure of
starter metal
(V) Faulty fuel injection pump
(3) Plunger sticks
(4) Oil leakage from exhaust valve
(5) Air inside pump
(6) Damaged exhaust valve spring
(1) Worn plunger
(2) Damaged
plunger spring
STARTING
TROUBLE
(I) Pinion gears do not mesh
(II-1) Tighten.
(II-2) Repair using sandpaper.
(II-3) Replace.
(II-4) Repair using sandpaper
(Type 500 600).
(II-5) Replace.
(II-6) Undercut and repair or replace.
(II-7) Replace.
(II-8) Replace with thicker or shorter wire.
(II-9) Charge.
(1) Loose battery
starter terminal
(2) Faulty connection in
engage magnet switch
(4) Commutator
rough and dirty
(3) Worn brushes
(II) Ring gears do not mesh
(1) Imperfect priming of fuel oil system
(2) Injection cut off due to faulty governor
(5) Fuel oil tank cock closed
(6) Clogging in fuel oil pipe
(8) Water in fuel oil tank
(7) Damaged fuel oil supply pump
(4) Insufficient fuel oil in tank
(3) Clogging of fuel inlet filter
(III) Fuel oil not injected
(1) Faulty valve seat
(2) Sticking of valve needle
(3) Worn valve needle
(4) Clogged outlet
(5) Low injection pressure
(IV) Faulty fuel injection valve
(VI) Faulty fuel injection system
(1) Fuel injection pump
timing irregular
(2) Loose high pressure fuel pipe
(3) Damaged high pressure fuel pipe
(2) No tappet clearance
(3) Faulty gasket packing
(4) Upper part of cylinder liner worn
(7) Insufficient tightening of head bolts
(8) Damaged valve spring
(5) Worn piston ring
(6) Piston ring sticks
(1) Air leakage from suction/exhaust valves
(4) Air in high pressure fuel pipe
(VII) Leakage of pressurized air
(5) Clogging of suction/exhaust pipes
(4) Faulty engine starter
(3) Governor handle is in stop position
(2) Faulty installation of
governor ring and lever
(1) Incorrect thickness
of gasket packing
(VIII) Miscellaneous