C2020IE - Pump 888 - Rollo - Rev. 1 June 2002 Page 6 of 8
3.7 Repairs
The following diagnostic table indicates the main anomalies which may be encountered, the probable causes and
possible solutions.
The anomalies shown are:
the pump fails to deliver lubricant;
irregular pressure;
irregular flow rate;
the lubricant does not arrive at the points to be lubricated.
In case of doubts and/or problems which cannot be resolved do not attempt to disassemble parts of the machine but
contact the Engineering Department of DROPSA S.p.A..
DIAGNOSTIC TABLE
INDICATION
CAUSE
REMEDY
The pump fails to
deliver lubricant
The tank is empty
The tank for grease has been
filled from the top and not by
using the appropriate side
connection
The pump element piston is
seized or the piston return
spring is broken
The pump is unable to operate
as the grease consistency
exceeds NLGI 2 (max.
recommended consistency).
The pump does not operate
because it has been running
with the tank empty creating
an air bubble within the pump
itself.
Refill the tank with clean lubricant, following the procedure in the section on
Maintenance.
Warning: if the tank has emptied without the electrical contact having signalled
the minimum level, check the minimum level contact.
Remove the connector cap for the supplementary pump element to purge the air
by running the pump until grease exits free from air bubbles. Replace cap B and
continue running the pump until grease exits between the threads and the cap
body, then fully tighten the cap.
Replace the pump element.
Remove the tank from the pump, remove the unsuitable grease and wash the
tank and filter with petrol.
Disassemble the pump and wash with petrol. Reassemble and refill the tank
(using the side connector equipped with a filter) with suitable grease and run the
pump, ensuring that the grease exits free from air bubbles. If necessary remove
the air vent cap B (See fig. on page 6) and purge as in the previous point.
Irregular pressure
Pressure regulating valve (by-
pass) dirty.
Disassemble the parts shown in diagram A (see fig. on page 6) and wash them
with petrol. Also clean the valve seating. Check the condition of the components
and replace where necessary.
Before reassembling the valve, check that sealing ring 18818 is not damaged.
Irregular flow rate
The flow is irregular due to
dirt in the system.
Remove the pump element from the pump body and completely disassemble it.
Check and clean all the pieces and reassemble.
Hold the pump element in wooden jaws to protect the lapped finish.
The lubricant does
not arrive at the
points to be
lubricated.
The lubricant has saponified in
the tubing and in the dosers.
Detach the feed tubing to determine that this is the problem.; where necessary,
use a high pressure (500 – 600 bar) hydraulic pump to purge the bearings of
saponified grease; the same operation must be carried out on all the connecting
tubing in the affected zone, then purge the dosers and, to finish, disconnect the
input tube to the dosers and, with the pump running, ensure that lubricant exits
from the tubing; where it does not, purge the tubing between the doser and the
pump and between the master doser and the secondary dosers. At the end of the
operation, check the working pressure of the system and set the maximum
pressure valve to 150 bar.
3.8
Dangers present in use
The verification of conformity with the essential safety requirements and regulations of the Machine Directive is
effected by means of the compilation of a check list which has been pre-prepared and is contained in the
technical