Replacing The Mechanical Seal Mchzs; Disassembling The Pump; Disassembling The Bearing Housing On The Drive Side; Disassembly Of The Ball Bearing - Johnson Pump MCHZ Instruction Manual

MCHZ
7.3.2
7.3.3
7.3.4
7.3.5
7.3.6
MCHZ/EN (0912) 4.2

Replacing the mechanical seal MCHZS

If only a mechanical seal has to be replaced the pump will have to be disassembled first.
Then the relevant bearing housing will have to be removed. For this see paragraph 7.3.4
and paragraph 7.3.8. Then see paragraph 7.3.6 for disassembly of the mechanical seal.

Disassembling the pump

1 Uncouple the inlet and outlet pipes. Make sure that they are sufficiently supported.
2 Slacken the foundation bolts and remove the pump from the pipe work.

Disassembling the bearing housing on the drive side

1 Uncouple the coupling halve from the pump shaft (0570) and remove the key (0200).
2 Only for MCHZS: Slacken the balance pipe (0670).
3 Place the pump vertically in a support, with the shaft end up.
4 Remove the rubber V-ring and the bearing cover (0110).
5 Slide the inner rubber V-ring over the shaft and slacken the inner bearing cover
(0110). This is now free from the pump shaft.
6 Remove the outer external circlip (0220) and the filling ring (0100) from the pump
shaft.
7 Slacken the bolts (0290) and pull the bearing housing (0010) vertically from the
pump section. The bearing will be pulled from the pump shaft.
8 Remove the lower external circlip (0220) and the filling ring (0100) from the pump
shaft.
9 Remove the bearing cover and the rubber V-ring from the pump shaft.
10 Only for MCHZ: Disassemble the gland (0130) and the packing rings (0150).

Disassembly of the ball bearing

1 Remove both internal circlips (0230) from the bearing bracket.
2 Using a suitable bush which rests on the outer ring, press the bearing out of the
bearing bracket.

Disassembling the mechanical seal MCHZS

1 Remove the seal cover (0050) from the pump shaft and remove the static ring from
the mechanical seal.
2 Slide the rotating ring for the mechanical seal (0130) off the pump shaft.
If the reason for disassembly was to replace the mechanical seal, the new mechanical
seal can now be fitted. See from paragraph 7.4.5 for this.
Disassembly and assembly 29