Replacing The Grinder System - Grundfos SEG Serie Montage- Und Betriebsanleitung

• Cable entry
Make sure that the cable entry is watertight and
that the cables are not sharply bent and/or
pinched.
See section 10.6 Service
• Pump parts
Check the impeller, pump housing, etc. for
possible wear. Replace defective parts.
See section 10.6 Service
• Ball bearings
Check the shaft for noisy or heavy operation (turn
the shaft by hand). Replace defective ball
bearings.
A general overhaul of the pump is usually
required in case of defective ball bearings or poor
motor function. This work must be carried out by
Grundfos or a service workshop authorised by
Grundfos.
• Grinder system/parts
In case of frequent choke-ups, check the grinder
system for visible wear. When worn, the edges of
the grinding parts are round and worn.
Compare with a new grinder system.

10.2 Replacing the grinder system

Warning
Before starting work on the pump,
make sure that the fuses have been
removed or the mains switch has been
switched off. Make sure that the power
supply cannot be accidentally switched
on.
All rotating parts must have stopped
moving.
Warning
Beware of the sharp edges on the
impeller, grinder head and grinder ring.
During service the painted surface may
Caution
be damaged. Remember to restore the
painted surface by applying new paint.
For position numbers, see page 592.
kits.
kits.
Dismantling
1. Loosen screw (pos. 188a) in one of the pump
feet.
2. Loosen grinder ring (pos. 44) and open the
bayonet socket by knocking/turning the grinder
ring 15 to 20 ° clockwise. See fig. 11.
Fig. 11 Removing the grinder ring
3. Carefully prise grinder ring (pos. 44) out of the
pump housing with a screwdriver.
Make sure that the grinder ring does not get
stuck against the grinder head!
4. Insert a punch into the hole in the pump housing
to hold the impeller.
5. Remove screw (pos. 188a) in the shaft end and
lock ring (pos. 66).
6. Remove grinder head (pos. 45).
Adjusting the impeller clearance
See fig. 12.
1. Gently tighten adjusting nut (pos. 68) (spanner
size 24) until impeller (pos. 49) cannot rotate any
more.
2. Loosen the adjusting nut by 1/4 turn.
Fig. 12 Adjusting the impeller clearance
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