Models 947, 948 and 960 Leak Detectors Operations and Service Manual
B-23
B.5.1.1 Removing the Wet System Forepump
To perform this procedure:
1. Disconnect the mains power supply and make sure that all pumps are off.
WARNING
Disconnect power from the 947/948/960 before performing any
maintenance procedure that requires physically disconnecting
any part of the system.
CAUTION
Models 948/960 only:
Remove, empty, and clean the cold trap
whenever power is removed. Refer to “Liquid Nitrogen Cold
Trap (Models 948/960 only)” on page 4-10.
WARNING
To avoid injury, use proper lifting techniques when moving
pumps. Your system may have pumps that require two people
to move them safely.
2. Remove the front panel.
3. Remove the left side panel.
4. Unplug the power plug of the pump from the 947/948/960.
5. Drain the oil following the instruction included in the pump manual.
6. Remove the NW25 clamp from the left manifold.
7. Remove the centering ring and O-ring, and place all connections where the oil will not
contaminate other parts.
8. Loosen the lower radiator clamp holding the tygon tubing around the bottom section of
the foreline.
9. Remove the bottom section of the foreline, and place it where oil will not contaminate
other parts.
10. Remove the NW16 clamp from the exhaust connection.
11. Remove the exhaust fitting.
12. Remove the centering ring and O-ring, and place all connections where the oil will not
contaminate other parts.
13. Working from beneath the main cabinet, remove the four nuts from the mounting bolts
that connect the pump to the bottom of the main cabinet (Figure B-10 on page B-15).
14. Remove the pump from the 947/948/960.
