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68
Twin Disc, Incorporated
Troubleshooting
Marine Transmission Service Manual #1020667
Table 8. Troubleshooting Chart
Symptom
Cau se
Remedy
1.
Low main oil pressure
1-1
Partially clogged oil
strainer
1-1
Remove and clean oil
strainer.
1-2
Stuck pressure regulation
piston.
1-2
Disassemble the valve
and clean the piston.
1-3
Broken piston rings on
clutch shaft(s).
1-3
Remove the collector
and inspect piston rings.
1-4
Damaged or worn oil
pump assembly.
1-4
Replace damaged or
worn oil pump assembly
(pump is not ser viceable)
1-5
Incorrect linkage
adjustment to control
valve assembly.
1-5
Adjust linkage so that
control valve stem is
indexed properly by
detent.
1-6
Clogged or plugged
orifice in orifice plate of
control valve assembly.
1-6
Remove orifice plate
cover. Clean parts.
1-7
Shimming required
between regulator springs
and rate-of-rise piston.
1-7
Shim as required.
1-8
Engine idle speed too
low.
1-8
Raise engine speed.
2.
No oil pressure, or
erratic low pressure at
control valve tap.
2-1
Oil pump suction strainer
plugged.
2-1
Remove and clean
strainer.
2-2
Oil level low.
2-2
Check oil le vel and
correct.
2-3
Air leak on suction side of
pump.
2-3
Correct cause of air leak.
2-4
Pump dri ve on reverse
clutch shaft broken.
2-4
Disassemble and repair
as required.
2-5
Regulating valve stuck in
open position
2-6
Remove, disassemble,
clean and repair the
regulating valve.
2-6
Oil pump defective
2-7
Replace oil pump.
2-7
Leaking heat exchanger
has caused oil to be lost
over board.
2-7
Replace heat exchanger
Symptom
Cau se
Remedy
1.
Low main oil pressure
1-1
Partially clogged oil
strainer
1-1
Remove and clean oil
strainer.
1-2
Stuck pressure regulation
piston.
1-2
Disassemble the valve
and clean the piston.
1-3
Broken piston rings on
clutch shaft(s).
1-3
Remove the collector
and inspect piston rings.
1-4
Damaged or worn oil
pump assembly.
1-4
Replace damaged or
worn oil pump assembly
(pump is not ser viceable)
1-5
Incorrect linkage
adjustment to control
valve assembly.
1-5
Adjust linkage so that
control valve stem is
indexed properly by
detent.
1-6
Clogged or plugged
orifice in orifice plate of
control valve assembly.
1-6
Remove orifice plate
cover. Clean parts.
1-7
Shimming required
between regulator springs
and rate-of-rise piston.
1-7
Shim as required.
1-8
Engine idle speed too
low.
1-8
Raise engine speed.
2.
No oil pressure, or
erratic low pressure at
control valve tap.
2-1
Oil pump suction strainer
plugged.
2-1
Remove and clean
strainer.
2-2
Oil level low.
2-2
Check oil le vel and
correct.
2-3
Air leak on suction side of
pump.
2-3
Correct cause of air leak.
2-4
Pump dri ve on reverse
clutch shaft broken.
2-4
Disassemble and repair
as required.
2-5
Regulating valve stuck in
open position
2-6
Remove, disassemble,
clean and repair the
regulating valve.
2-6
Oil pump defective
2-7
Replace oil pump.
2-7
Leaking heat exchanger
has caused oil to be lost
over board.
2-7
Replace heat exchanger
Symptom
Cau se
Remedy
1.
Low main oil pressure
1-1
Partially clogged oil
strainer
1-1
Remove and clean oil
strainer.
1-2
Stuck pressure regulation
piston.
1-2
Disassemble the valve
and clean the piston.
1-3
Broken piston rings on
clutch shaft(s).
1-3
Remove the collector
and inspect piston rings.
1-4
Damaged or worn oil
pump assembly.
1-4
Replace damaged or
worn oil pump assembly
(pump is not ser viceable)
1-5
Incorrect linkage
adjustment to control
valve assembly.
1-5
Adjust linkage so that
control valve stem is
indexed properly by
detent.
1-6
Clogged or plugged
orifice in orifice plate of
control valve assembly.
1-6
Remove orifice plate
cover. Clean parts.
1-7
Shimming required
between regulator springs
and rate-of-rise piston.
1-7
Shim as required.
1-8
Engine idle speed too
low.
1-8
Raise engine speed.
2.
No oil pressure, or
erratic low pressure at
control valve tap.
2-1
Oil pump suction strainer
plugged.
2-1
Remove and clean
strainer.
2-2
Oil level low.
2-2
Check oil le vel and
correct.
2-3
Air leak on suction side of
pump.
2-3
Correct cause of air leak.
2-4
Pump dri ve on reverse
clutch shaft broken.
2-4
Disassemble and repair
as required.
2-5
Regulating valve stuck in
open position
2-6
Remove, disassemble,
clean and repair the
regulating valve.
2-6
Oil pump defective
2-7
Replace oil pump.
2-7
Leaking heat exchanger
has caused oil to be lost
over board.
2-7
Replace heat exchanger
Summary of Contents for MG-5170DC
Page 3: ...Document Number 1020667 July 2002 Marine Transmission Service Manual ...
Page 4: ......
Page 108: ...108 Twin Disc Incorporated Disassembly Marine Transmission Service Manual 1020667 ...
Page 114: ...114 Twin Disc Incorporated Cleaning and Inspection Marine Transmission Service Manual 1020667 ...
Page 166: ...166 Twin Disc Incorporated Assembly Marine Transmission Service Manual 1020667 ...
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Page 206: ...206 Twin Disc Incorporated Special Tools Marine Transmission Service Manual 1020667 Notes ...
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Page 208: ...208 Twin Disc Incorporated Special Tools Marine Transmission Service Manual 1020667 Notes ...
Page 224: ...224 Twin Disc Incorporated Illustrations Marine Transmission Service Manual 1020667 Notes ...
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Page 226: ...226 Twin Disc Incorporated Illustrations Marine Transmission Service Manual 1020667 Notes ...
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Page 228: ...228 Twin Disc Incorporated Illustrations Marine Transmission Service Manual 1020667 Notes ...
Page 230: ...230 Twin Disc Incorporated Engineering Drawings Marine Transmission Service Manual 1020667 ...
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Page 247: ...CAUTION ...
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