PREVOST H3-41 Maintenance Manual page 963

TROUBLESHOOTING, POSSIBLE DEFECTS, ELIMINATION
PROBLEM
Clutch does not close any more,
no current stream
Clutch does not close in spite of
current stream
Clutch slips when switched on
(causes the destruction of the
clutch by premature wear),
Clutch does not
immediately when switched off,
this will cause a premature wear
of the clutch), shrieking noise
Clutch does not open any more,
voltage supply is in order
Permanent grinding noise
Writer:
EL
CAUSE
Intermittent contact in the plug
Contact corroded
Connection cable defect
Insufficient voltage supply
Impurities in the working gap
(foreign matters)
Insufficient voltage supply
Friction surface polluted by small
quantities of
substances
Heat penetration in the clutch by
slipping V-belts
penetration in the bearing or
overheating of the clutch
Incorrect distance between coil
and rotor (coil not in line with the
rotor), thus the switchable torque
is reduced
Clutch worn, working gap too big
(app. 1,2 mm), friction partner
blue
open Voltage supply not completely
interrupted
Clutch worn and friction partners
welded to each other on the
friction surface
Coil not correctly centered or not
firmly screwed down
Compressor bearings
causes friction between coil and
rotor.
SOLUTION
Check plug
Clean contact
Repair cable, replace coil
Check supply voltage
Disassemble
foreign matters and assemble it
again
Check power supply
Disassemble clutch, clean friction
greasy/oily surfaces
assemble it again.
Disassemble
thus grease friction
already damaged components.
After reassembly of the clutch,
tension V-belts correctly
Disassemble clutch, check cone
for cleanness. Check the seat of
the feather key, check the seat of
the coil.
Replace clutch or component
Check
switching the coil ON/OFF and
replace it if necessary
Replace clutch
Check coil, screw it down, or
replace it if damaged. Check
clutch
damages,
disassemble
bearing and friction surfaces,
replace
components.
defect, Replace bearings. Check coil
function. Replace it if damaged.
If clutch slips, replace whole
clutch due to friction damage.
MI18-37
Page 11 / 14
clutch, remove
with alcohol and
clutch. Clean
surfaces or replace
circuit element for
for consequential
eventually
clutch, check
eventually damaged
<QF7720955 rev 7>