Possible causes
Possible causes
A.Oil pressure too low
A.Oil pressure too low
(1) Low oil level
(1) Low oil level
(2) Air sucked from suction
(2) Air sucked from suction
side.
side.
(3) Clogged oil filter
(3) Clogged oil filter
(4) Insufficient discharge of
(4) Insufficient discharge of
pump
pump
(5) Main relief valve coil
(5) Main relief valve coil
spring deteriorated
spring deteriorated
(6) Seal ring or O-ring
(6) Seal ring or O-ring
damaged or worn.
damaged or worn.
B.Flywheel damaged or in
B.Flywheel damaged or in
contact with other parts
contact with other parts
A.Improper oil is used or
A.Improper oil is used or
bubbles are foamed.
bubbles are foamed.
(1) Air sucked from suction
(1) Air sucked from suction
side.
side.
(2) Torque converter oil
(2) Torque converter oil
pressure is too low and
pressure is too low and
bubbles are foamed.
bubbles are foamed.
B.Clutch slips
B.Clutch slips
(1) Low oil pressure
(1) Low oil pressure
(2) Seal ring worn
(2) Seal ring worn
(3) Clutch piston ring worn
(3) Clutch piston ring worn
(4) Clutch disks are burned
(4) Clutch disks are burned
and plates deformed.
and plates deformed.
C. Link lever between brake
C. Link lever between brake
shift and valve spool is
shift and valve spool is
improperly positioned.
improperly positioned.
Engine power drops
Engine power drops
Checking method
Checking method
Check oil level
Check oil level
Check joints and pipe
Check joints and pipe
Disassemble and check
Disassemble and check
Disassemble and check
Disassemble and check
Check spring tension
Check spring tension
Disassemble,
Disassemble,
check
check
and
and
measure.
measure.
Drain a small quantity of oil
Drain a small quantity of oil
and check for presence of
and check for presence of
foreign matter.
foreign matter.
Check
Check
Check joints and pipes
Check joints and pipes
Measure pressure.
Measure pressure.
Measure pressure
Measure pressure
Disassemble,
Disassemble,
check
check
and
and
measure
measure
Disassemble and check
Disassemble and check
Disassemble and check,Start
Disassemble and check,Start
engine and place direction
engine and place direction
control lever in forward,
control lever in forward,
reverse and neutral respec-
reverse and neutral respec-
tively.Truck runs with the
tively.Truck runs with the
lever in neutral but not in
lever in neutral but not in
fwd.or bwd.
fwd.or bwd.
Check and measure.
Check and measure.
Check STALL rmp.Check
Check STALL rmp.Check
working sound of enginge.
working sound of enginge.
Check maximum rmp of
Check maximum rmp of
engine with gears in neutral.
engine with gears in neutral.
Remedy
Remedy
Add oil
Add oil
Retighten and replace packing
Retighten and replace packing
Clean or replace
Clean or replace
Replace
Replace
Replace
Replace
Replace
Replace
Replace
Replace
Retighten or replace
Retighten or replace
Adjust pressure
Adjust pressure
Adjust pressure
Adjust pressure
Replace
Replace
Replace
Replace
Replace
Replace
Adjust
Adjust
Adjust or repair engine
Adjust or repair engine
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-52-
-52-
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