Dawson EMV-220 METRIC, Инструкция оператора/Перечень запасных частей

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7.4.2 Drain line being pressurised – check that the line is not connected to a
supply line e.g. the pressure line from a breaker circuit.
7.4.3 Long drain hose or the hose bore too small – either of these can
contribute to an increase in back pressure.
7.4.4 Extremely cold weather – if the base machine hydraulic oil is of an
inappropriate viscosity grade for the ambient temperature it may well be
too thick. This will cause an increase in back pressure in the drain hose.
7.4.5 Faulty Blow-Off Valve on the motor casing – check that this has a
minimum crack pressure of 6 bar and a maximum of 7 bar. Replace if
unsure using a new calibrated valve and a new sealing ring.
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have little or know leakage.
The drive motor case seal has been blown, typically because the drain line
pressure has been exceeded – see also section 7.4.
The unit will need to be removed from the job site and repaired in a suitably
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oils.
Once in the workshop drain the oil from the gearbox and inspect the oil for
signs of debris. If only the seal has blown out without any damage to the motor
casting then it may be possible to repair the motor with an authorised Volvo
(VOAC) distributor, change the gear oil and rebuild the unit.
If however, the motor casting has also been damaged in the area of the seal
housing it will be necessary to completely inspect the inside of the gearbox.
Remove the gearbox lid and inspect the gear teeth and inspect all bearings.
Check the gears for any signs of damage. Remove all bearing covers from the
gearbox sides and inspect the outer races for signs of grooves or any other
contamination or damage – look at the rollers in each bearing. The bearings
and all running faces should be in perfect condition, if not they will need to be
replaced. Consult with the manufacturer at this stage or one of their approved
distributors – it is strongly recommended that the unit be repaired by the
manufacturer in order to ensure correct procedures and materials are used for
an effective repair
7.5
OIL BLOWING OUT
OF THE GEARBOX
BREATHER VALVE & THE
GEAR BOX IS FULL OF
OIL