4
Maintenance
22
Pump P-960
User Manual 18-1172-73 Edition AA
4.5
Replacing the connection part O-rings
Liquid appearing between the connection part and the pump assembly,
irregular flow, or unstable pressure might indicate that an O-ring in the
connection part is damaged.
4.5.1
Required spare parts and tools
•
O-ring kit (see Ordering information for code no.)
4.5.2
Replacing an O-ring
To replace an O-ring:
1
Remove the connection part according
to section 4.4.2 Removing the
connection part.
2
Remove the faulty O-ring carefully to
avoid making scratches on the
connection part.
3
Fit the new O-ring in position.
4
Reinstall the connection part
according to section 4.4.3 Installing
the connection part.
4.6
Cleaning and replacing the check valves
Faulty operation of the check valves is usually indicated by irregular
flow, very low flow, or unstable pressure traces. Probable causes are air,
dirt, or a damage in a check valve preventing it from closing to seal and
hold the pressure. Liquid appearing at a banjo fitting might indicate
that a check valve O-ring is damaged.
First try to clean the check valves in-place by pumping 100% ethanol
for approximately 10 min. If this does not correct the problem, follow
the instructions to remove and then clean the valves. If necessary, a
check valve or O-rings might need to be replaced.
4.6.1
Required spare parts and tools
•
Check valve (there are four different check valves. See Ordering
information for code nos.)
•
O-ring kit (see Ordering information for code no.)
•
Hex wrench, 4 mm
•
Screwdriver, flat-headed, width 5.0–5.5 mm
O-ring (x7)
18117273aa.book Page 22 Thursday, July 3, 2003 5:13 PM