Gasboy XU2A - Manual (Page 18)

Pump Maintenance
Page 18 MDE-4320 Gasboy UHF Pump, Blackmer® XU2A Rebuild Kit Installation Manual • June 2004
section of this manual.
1 Drain the pump and system as required.
2 Starting on the inboard (driven) end of the pump, clean the pump shaft thoroughly, making
sure he shaft is free of nicks and burrs. This will prevent damage to the mechanical seal when
the inboard head assembly is removed.
3 Remove the inboard bearing cover capscrews (28) and slide the inboard bearing cover (27A)
and gasket (26) off the shaft. Discard the gasket. The dirt shield will come off with the bearing
cover. Inspect dirt shield and replace as required.
4 Remove the outboard bearing cover capscrews (28) and bering cover gasket (26). Discard the
bearing cover gasket.
5 Remove the head capscrews (21) and carefully pry the head (20) away from the cylinder (12).
6 Slide the head off the shaft. The head O-ring (72), bearing (24), and mechanical seal (153) will
come off with the head assembly. Remove and discard the head O-ring.
a. Pull the bearing (24) from the housing in the head.
b. To remove the mechanical seal, use two screw drivers against the backside of the seal
jacket to gently push the seal from the head (see
Figure 3:Mechanical Seal Removal ). Use
care when placing the screw drivers to prevent damage to the seal faces. Remove and
discard the seal O-rings.
Figure 3: Mechanical Seal Removal
7 Pull the rotor and shaft (13) from the cylinder. While one hand is pulling the shaft, the other
hand should be cupped underneath the rotor to prevent the vanes (14) and pushrod (77) from
falling out. Carefully set the rotor and shaft aside for future vane replacement and reassembly.
8 Remove the remaining components from the outboard side of the pump as instructed in steps 7
and 8 above.
Pump Assembly
Before reassembling the pump, inspect all component parts for wear or damage and replace as
required. Wash out the bearing/seal races of the head and remove any burrs or nicks from the