17
LI 4431.00 (IT-EN)
Operating and maintenance instructions
EN
6.4 Exhaust filters replacement
Very dirty exhaust filters may cause a considerable pump temperature increase and in
extreme cases oil lubricant spontaneous ignition.
Maximum allowed pressure in the tank is 0,6 bar measured at the maximum capacity
(when the pump is working with the inlet open to atmospheric pressure).
If a pressure gauge has been fitted to the tank, check the exhaust filter blockage with
the pump warm.
To replace the filter, remove the cover (pos. B2) by unscrewing its screws (pos. B1).
Unscrew the screw (pos. B4), remove the washers (pos. B5-B6) and then the fixing
cartridge disk (pos. B7).
Replace all the exhaust filters (pos. B) and their O Rings (pos. B8). Reassemble the fixing
cartridge disk, the washers and tighten the screws.
Reassemble the discharge cover. If necessary, replace the gasket (pos. B3).
6.5 Float valve
If the float valve doesn’t operate well, you may notice:
- the oil carry out from the discharge port
- pump performance loss.
The reasons could be as follows:
- oil recovery line is blocked or the float valve mechanism got blocked due to dirties or
sludges.
- oil recovery line doesn’t close perfectly due to dirties or because the seal is worn.
In this case, the float valve must be disassembled, cleaned and then its good operation
must be checked.
Remove the cover Fig. 9 (pos. B2) unscrewing its screws (pos. B1). Remove the float
valve (pos. Z) from its housing after having unscrewed its grub-screw (pos. Z1). Clean the
float valve and its internal reduction fitting, with compressed air by blowing the opposite
direction with respect to the normal oil flow. Fit the float valve in its housing. Check the
float valve good operation before closing the cover (pos. B2).
- Switch the pump on without having any oil deposit and check if it achieves the limit
pressure.
- Fill with oil until the valve
opens. Wait until it closes,
while checking if the pump
keeps its ultimate pressure
constant.
If not, the float valve must
be replaced completely.
Fig.10
Z
Z1