Foley Engines ZF 45 C Repair Manual page 34

Syptom
11. Fluid leakage at
breather
12. Fluid leakage at
joints
13. Transmission noise
becomes louder
14. Chattering
transmission noise
mainly at low engine
speed
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Repair Manual and Spare Parts List ZF 45C / 63C / 88C
Possibly cause
11.1 Excessive fluid in
transmission
12.1 Bolts are not tight
12.2 Seals on bolts have
used several times
12.3 Mating faces are
contaminated, no surface
seal applied
13.1 Fluid level too low so
that pump sucks in air.
13.2 Damage starting on
flexible coupling due to
wear or fatigue, possible
due to misalignment
between engine and
transmission.
13.3 Beginning damage of
bearings in transmission,
e.g. due to torsional
vibrations, running without
fluid, overload,
wrong alignment of
transmission excessive
engine output
13.4 Beginning damage of
gearings, e.g. due to
torsional vibrations,
running without fluid,
overload
13.5 Dirty fine filter
14.1 The engine or propeller
generate torsional
vibrations in the drive
unit which produce a
"chattering" noise in the
transmission
14.2 Misaligned propeller
shaft on output
Remedy
Pump excessive fluid out
with commercial hand pump
Tighten bolts with prescribe
torque.
Replace seals, tighten bolts
with prescribed torque
Unscrew housing half, finish
mating faces with oilstone
or finishing file, apply surface seal.
Assemble transmission, tighten bolts
with correct torque.
Top up with fluid to
marking on dipstick.
Replace flexible coupling.
Check alignment between
engine and transmission.
Disassemble transmission,
replace bearings concerned
and other faulty parts. Find
causes and remedy.
Disassemble transmission,
remove faulty parts.
Clean or replace fine filter
Mount a flexible coupling
with another stiffness
factor between engine and
transmission; a coupling
with a higher stiffness
factor might be sufficient.
Otherwise analyse the
torsional vibrations to find
out the required stiffness
for the coupling.
Mount and align propeller
shaft strictly according to
instructions issued by
shaft manufacturer.