Grundfos CR 32, CR 45, CR 64, CR 90, CRN 32 Service Manual

TORQUES

Position
Number

7a Screw for Guard ..........................................6 ft.-lbs./8 Nm

9 Coupling Screws ..................................... 63 ft.-lbs./85 Nm

26b Allen Screw for Strap ............................11 ft.-lbs./15 Nm

28 Allen Screw Motor

Stool to Pump Head ..............................46 ft.-lbs./62 Nm

28a Allen Screw for Motor

1/2" x 13 UNC, 3-40 HP ........................ 30 ft.-lbs./40 Nm

5/8" x 11 UNC, 50-60 HP ...................... 59 ft.-lbs./80 Nm

31 Allen Screw for Bottom

Stationary Bearing ...................................... 6 ft.-lbs./8 Nm

36 Staybolt Nut .......................................... 74 ft.-lbs./100 Nm

48 Split Cone Nut ......................................... 52 ft.-lbs./70 Nm

58a &

58d Allen Screw Seal Carrier ....................... 46 ft.-lbs./62 Nm

67 Allen Screw for Shaft Bearing.............23 ft.-lbs./31 Nm

113 Allen Set Screw for Shaft Seal ................. 6 ft.-lbs./8 Nm

CONTENTS

Dismantling Procedures ...................................................Page 2

When Should A Part Be Replaced ? ...............................Page 12

Reassembly Procedures ................................................. Page 13

Setting The Coupling Height ..........................................Page 21

Order of Stage Assembly - CR, CRN 32 ........................Page 23

Order of Stage Assembly - CR, CRN 45 ........................Page 24

Order of Stage Assembly - CR, CRN 64 ........................Page 25

Order of Stage Assembly - CR, CRN 90 ........................Page 26

CR, CRN 32•45•64•90

Dismantling &

Reassembly

GRUNDFOS

CR SERVICE MANUAL

4

2

Dismantling Procedures CR, CRN 32•45•64•90

1

2 3

Use an Allen wrench with an 8 mm tip
to loosen and remove the Coupling
Screws (Pos. 9) from the Coupling
Halves (Pos. 10a).

To remove the coupling halves, insert
a at/slot blade screwdriver in the
coupling gap and twist to free the rst
coupling half.

Loosen, b u t do not r em o v e ,
Coupling Guard Screws (Pos. 7a).
Remove Coupling Guards (Pos. 7)
from the Motor Stool (Pos. 1a).

In the instructions below, the numbers in parenthesis (7) indicate the position number of that part as it is shown on the Parts List and Kits diagram.

To free/remove the remaining cou­pling half, strike the upper edge of the
coupling half with a rubber mallet.

Note: If you have multiple pumps,
do not i nterchange c o u pling
components, they are a matched set.

7

Loosen, but do not remove, the
3 mm Set Sc rews (Pos. 11 3)
from the Shaft Seal (Pos. 105) .

These in structions co ver the
repair of the pump after it has
been isolated from the system.
Before removing the pump from
the system, make sure all valves
are closed. Relieve any built-up
pressure by opening the vent plug
screw. The power source should be
turned off and locked out before
starting any work. Removal of
eld wiring to the motor may be
required. Color coding or numbering
the wires will aid in reinstallation.

For shaft seal change only

on a Standard unit or a Cool Top®,

follow steps 1 to 8.

Pumps built with Back-to-Back seals,

follow steps 1 to 11.

Pumps built with Tandem/Quench

seals, follow steps 35 to 49.

5

Remove the 8 mm socket Allen Screws
(Pos. 58a) from the Seal Retainer (Pos.

58). Remove the retainer.

6

Remove the Motor-to-Pump Bolts (Pos.
28a). Lift the motor off the pump.

Motor removal is not necessary. Skip
to step 6.

15 HP and UP

3 - 10 HP

3

Dismantling Procedures CR, CRN 32•45•64•90

11

Loosen and remove the 24 mm
Staybolt Nuts (Pos.36) and Washers
(Pos. 66a). For Standard pumps, skip
to dismantling step 50. For Cool Top

units, continue with steps 12 to 20.
For Back-to-Back units, continue with

steps 21 to 34.

Pos. 105

9

Cartridge Seals

Will lift out as a complete assembly.

Loosen and remove the 8 mm hex socket
Allen Screws (Pos. 28) connecting the
motor stool to Pump Head (Pos. 2).

To remove the Motor Stool (Pos. 1a):

Loosen the allen screws connecting the
motor stool to the pump head. Leave the
motor stool attached to the motor and/or
bearing ange to protect the motor shaft
and bearing ange shaft.

10

8

Use two at/slot blade screwdrivers
to pry the seal loose. Lift the seal
(Pos. 105) completely off of the shaft
(Pos. 51). For seal change only on
Standard and Cool Top pumps, go to
the Reassembly section step 47. For
STACK® (Pos. 80) replacement, Back­to-Back Inboard Seal (Pos. 105b) and
Cool Top Connecting Pipe (Pos. 149)
removal, continue with step 10.

15 HP and UP

3 - 10 HP

Dismantling Procedures CR, CRN 32•45•64•90

4

14

To remove the upper sleeve, diagonally
grip the Staybolts (Pos. 26). Using
your thumbs, press against the
sleeve to release the sleeve from the
middle pump head. If it does not move
freely, light blows with a rubber mallet
might be required. Once loose, lift the
sleeve off.

Cool-Top®

Remove the upper most Pump Head
(Pos. 2b), Upper Sleeve (Pos. 55a)
and middle Pump Head (Pos. 2c) as a
complete assembly if it has not leaked,
then skip to step 16. If the assembly
has leaked follow steps 13 to 15.

Remove the upper most pump head.
This may require light upward blows
with rubber mallet to the underside
of the pump head.

13

12

17

Loosen and
remove the

8 mm hex socket

Retainer Screws

(Pos. 58d).

Remove

the Connecting

Pipe Retainer

(Pos. 58c).

Lift off the middle pump head. Lift off the Spacing ring (Pos. 116).

16

15

Remove t he O -ri ngs (Pos. 109a
and 109b). For reassembly of the
connecting pipe go to the Reassembly
section st ep 18. To co ntinue
disassembly, proceed to step 50.

Remove the Connecting Pipe (Pos.

149).

Place the connecting pipe into one
of the pump heads. Use 00SV2128
and a rubber mallet to drive out the
Retainer Ring (Pos. 47h) and Bushings
(Pos. 47g).

18

19

20

Dismantling Procedures CR, CRN 32•45•64•90

23

To remove the

Inboard Shaft

Seal (Pos. 105b)

loosen, but do

not remove, the

two 3mm

Set screws

(Pos. 113a) in
the Seal Driver
( Pos. 112). Lift

the seal driver

off of the shaft.

Back-to-Back Seal

Remove the upper most Pump Head
(Pos. 2b). This may require light
upward blows with rubber mallet to
the underside of the pump head.

To remove the Upper Sleeve (Pos.
55a), diagonally grip the Staybolts
(Pos. 26). Use your thumbs to press
against the sleeve to release the sleeve
from the middle pump head. If it does
not move freely, light blows with
a rubber mallet might be required.
Once loose, lift the sleeve off.

22

21

Remove the Spring (Pos. 108b), Spring/O-ring Cup (Pos. 106b), O-ring (Pos. 107b), Seal Driver (Pos. 111b), and Rotating Seal Face (Pos. 104b).

24

Remove the Retaining Washer (Pos.
59a).

Remove the lower most Pump Head
(Pos. 2), Spacing Ring (Pos. 116) and
middle Pump Head (Pos. 2c) with
Connecting Pipe (Pos. 149) as an
assembly. Light upward blows with
rubber mallet to the underside of
the lower most pump head might be
required.

25

26

27

5

Use specialty

tool, 00SV7902,

to loosen and

remove the

threaded Seal

Retainer

(Pos. 148).

Remove the connecting pipe.

Dismantling Procedures CR, CRN 32•45•64•90

Back-to-Back Seal (continued)

Use your finger to reach through
the center of the seal, then pull the
Stationary Seal from the connecting
pipe.

Remove the middle pump head and spacing ring.

29

28

Use an 8 mm Allen wrench to loosen and remove the Retainer Screw (Pos. 58d). Then,
remove the Connecting Pipe Retainer (Pos. 58c).

30

6

Use 00SV2128 and a rubber mallet to
drive out the Retainer Ring (Pos. 47h)
and Bushings (Pos. 47g).

31

Flip the pump head over and remove
the four Stack Compression Spacers
(Pos. 60). For reassembly of the
inboard seal, skip to the Reassembly
Secti on st ep 25. To co ntin ue
disassembly, proceed to dismantling
step 51.

32

Remove the O-rings (Pos. 109a and
109b).

33

34

To free/remov e the remainin g
coupling half, strike the upper edge
of the coupling half with a rubber
mallet. Note: If you have multiple
pumps, do not interchange coupling
components, they are a matched set.

Dismantling Procedures CR, CRN 32•45•64•90

37

Us e an Al len w ren c h wi t h
an 8 mm tip to loosen and
remove the Coupling Screws (Pos. 9)
from the Coupling Halves (Pos. 10a).

Tandem Seal

Loosen the top

Coupling Guard

Screw (Pos. 7a),

but do not fully

remove. Loosen

and fully remove

the lower screw.

Ti lt an d slid e

th e C ou pl in g

Guards (Pos. 7)

off of the system

fl us h pip in g.

Remove system  ush piping.

36

35

To remove the coupling halves, insert
a  at/slot blade screwdriver in the
coupling gap and twist to free the
 rst coupling half.

38

Loosen, but do not remove, the
3 mm Set Screws (Pos. 113) from
the Tandem Shaft Seal (Pos. 105c).

41

39

40

7

L oo s en a n d r em o ve t h e
8 mm hex socket All en Screws
(Pos. 58b) holding the seal housing.

42

Use two  at / slot blade screwdrivers
to pry the seal loose. Lift the seal (Pos.
105c) completely off of the shaft
(Pos. 51).

43

Regardless of the motor HP size
on Tandem Seal equipped pumps,
the motor must be removed to
chan ge the seals. Remove the
motor to pump bolts (Pos. 28a). Lift
motor off of motor stool (Pos. 1a).

Loosen and rem ove the 8 mm
hex socket Allen Screws (Pos. 28)
connecting the motor stool to Pump
Head (Pos. 2).

Dismantling Procedures CR, CRN 32•45•64•90

Tandem Seal (continued)

Remove the Tandem Seal Housing
O-ring (Pos. 109c).

44

48

8

45

Loosen, but do not remove, the
3 m m Set S c rews ( Pos. 1 1 3)
from the Shaft Seal (Pos. 105) .

46

Use two at/slot blade screwdrivers
to pry the seal loose. Lift the seal
completely off the shaft. For seal
change only, go to the Reassembly
se ctio n, step 47. To conti nue
disassembly, proceed to step 48.

Pos. 105

47

Cartridge Seals

Will lift out as a complete assembly.

49

Loosen and remove the 24 mm
Staybolt Nuts (Pos. 36) and Washers
(Pos. 66a).

Dismantling Procedures CR, CRN 32•45•64•90

50

Remove Pump Head (Pos. 2) (this may
require light tapping with a rubber
mallet to the underside of the pump
head to loosen). Once pump head is
loose, lift off of pump.

51

To remove Outer

Sleeve (Pos. 55),

grip staybolts

diagonally. Using

your thumbs,

press against

sleeve to release

the sleeve

from the pump

housing. Lift off

sleeve.

Lift the impeller STACK® (Pos. 80) off
the suction/discharge base (Pos. 6).
For Stack Replacement instructions,
go to Reassembly Section, step

15. To continue disassembly,
proceed with steps 54 to 66.

52

Loos e n the cham be r s tr a ps ,
remove 6 mm hex socket Allen
Screw (Pos. 26b), Washer (Pos. 26c),
and Chamber Straps (Pos. 26a).

54

53

Fi t a ssemb ly/di sas sem bly to ol
(00SV0003) to Stack. The tool consists
of different size spacing plates. Select
the plate which ts securely to the
Stack Interface (Pos. 44). Place holding
pin into the disassembly hole.

Remove the Upper Chamber (Pos. 3).

55

Loosen Split Cone Nut (Pos. 48) approximately two to three full turns with split cone
nut wrench (00SV0004). Flip tool over and give a sharp blow directly down against the
split cone nut. This will loosen the Split Cone (Pos. 49b) and allow the Impeller (Pos.
49a) to be lifted off the shaft. Lift off Chambers (Pos. 4 & 4a). Repeat this process until
all impellers are removed from Shaft (Pos. 51).

56

57

Remove Base Interface (Pos. 44).

9

Dismantling Procedures CR, CRN 32•45•64•90

58

To remo ve the s haft fro m the
assembly/disassembly tool, remove
the holding pin from the shaft and
lift shaft out of tool.

After inspecting the parts, if further
disassembly is required, proceed to
the next steps.

59

Remove bearing from shaft. Remove
6 mm hex socket Allen Screw (Pos. 67),
locking washers (Pos. 66b), washer
(Pos. 66), and journal bearing (Pos. 47b).
Loosening the allen screw may require
use of the holding pin as a countering
device so the shaft does not spin.

Depending on wear, the Neck Ring (Pos. 45),
Retainer (Pos. 65), and Holder (Pos. 45a)
may need to be removed. Using a at bar,
pry these components out of the chambers
and base interface as a complete assembly.

If wear or damage is minor, the neck
ring may be replace d u sing a screw­driver to twist and pry out the retainer.

Lift out the Neck Ring (Pos. 45).

60

To r e mo v e t h e C ha mb e r
Bearing (Pos. 47), Bearing Sleeve
(Pos. 47c), and Bearing Lock Ring
(Pos. 47d), place chamber upward
using the p unch ( 00SV 0015).
Dri ve the bearing downw ard.

61

62

If the Impeller Wear Ring (Pos. 49c) is
worn and the split cone nut/impeller
hub threads are not damaged, the
wear ring ma y be removed using
th e a pp ro pr ia te s up po rt t oo l,

• CR, CRN32 00SV0043

• CR, CRN45 00SV0044

• CR, CRN64 00SV0045

• CR, CRN90 00SV0046

al ong w ith t he w ear ring pul ler
(00SV0239) used to pry off the wear
ring. If the threads of the impeller hub are
damaged, a new impeller will be required.

10

Punch

Dismantling Procedures CR, CRN 32•45•64•90

Using a small screwdriver, remove
Sleeve O-rings (Pos. 37) from the pump
head and the suction/discharge base.

To remove the Bottom Bearing (Pos. 6g), loosen and remove the securing 5 mm Allen
Screw (Pos. 31) and Washer (Pos . 3 2) from the Suction/D ischarge Base
(Pos. 6). Using the bearing puller (00SV0002) and allen screw (00ID6595), insert
the bearing puller along with the allen screw at an angle until it passes through
the bearing. Once the bearing puller is under the bearing's lower edge, begin
turning the allen screw until the bearing has been pryed out of the housing.

63

64

26

Remove the four Stack Compression
Spacers (Pos. 60).

65

THE PUMP IS

NOW COMPLETELY

DISASSEMBLED.

11

Dismantling Procedures CR, CRN 32•45•64•90

When Should A Part Be Replaced?

Part Position(s) Minimum Operating Condition

Pump Head 2 Excessive pitting of these castings could cause leaks. Rusted
castings should have all seating areas cleaned to ensure proper
seating of O-rings.
Suction/Discharge 6
Base

Chambers 3, 4a, 4 Same as for impellers.

O-rings 37, 38, 38a, 100 Should be soft and pliable with no visible scars. Since they
are easily damaged and fairly inexpensive, it is recommended
they be replaced whenever the pump is disassembled.

Neck Ring 45 Should be free of visible wear on the inside edges.
Inside diameter for:
CR, CRN 32 = 66.2 mm
CR, CRN 45 = 73.9 mm
CR, CRN 64 = 86.3 mm
CR, CRN 90 = 93.8 mm

Bearing Ring 47a The diameter size difference between the Bearing Ring (Pos. 47a)
and the Bearing (47-47c) xed inside the intermediate
chambers should be no greater than 0.4 mm.

Bushing and Bearings 6g, 47, 47b, 47c The diameter size difference between the Bearing Ring
(Pos. 47a) and the Bearing (Pos. 47-47c) xed inside the intermediate
chambers should be no greater than 0.4 mm.

Impellers 49 (a, d, e & i) Should be free from physical markings except for the guide
vane welds. Any additional identations may result from:

(1) Cavitation - the implosion of vapor "bubbles" within the
impeller stack. Make sure the Net Positive Suction Head
Available for the pump meets the minimum Net Positive
Suction Head Required for the pump when runnning at the
required ow.

(2) Improper coupling height - If the coupling is not set to the
proper height (see step 54 & 57 of the Reassembly procedures) the
impellers are not suspended as they should be, but instead
they rub against the chambers, either above or below, causing
contact wear.

(3) Worn groove to Impeller Wear Ring (Pos. 49c) from system
sediments. Wear rings should be replaced, or impeller complete if
threaded area for split cone nut is damaged.

Shaft 51 Should show no signs of gouging or wear throughout its total
length. Use emery tool to remove shaft seal set screw marks.

Stack Compression Spacer 60 Should always be replaced.

Shaft Seal
Cartridge Complete 105 (a, b & c) Should seal without leakage

Refer to the Parts List and Kits section for a list of material numbers and spare part kits.

12

After pressing on a new Wear Ring
(Pos. 49c), or if using a new Impeller
(Pos. 49d, e, or i), place the complete impeller
over the shaft and seat into the interface
assembly. Slide the Split Cone (Pos. 49b)
down the shaft and into the recessed
area of the impeller hub. Use the split
cone nut tool (00SV0004) in the inverted
direction and rmly drive split cone into the
impeller. While performing this function,
care must be taken to avoid damaging
the threaded hub area of the impeller.

Fit the shaft into the assembly/
disassembly fixture (00SV0003).
Make sure the holding pin is inserted
into the assembly hole. Refer to
the diagrams on pages 22-26 for
the appropriate staging sequence.

Before reusing the Shaft (Pos. 51), use an
emery tool to smooth away shaft seal set
screw marks and make sure the main shaft
area is not worn. If the Journal Bearing (Pos.
47b) was removed, replace the journal bear­ing. Add the Clamping Washer (Pos. 66), and
two Locking Washers (Pos. 66b). Loosely
thread the 6mm Allen Screw (Pos. 67) onto
the shaft. To ensure journal bearing and
clamp washer alignment, slide the Bottom
Bearing (Pos. 6g) over these items. Place the
holding pin through the shaft to prevent
it from spinning while the allen screw is
tightened to a torque of 23 ft.-lbs./31Nm.
Remove the hold pin and the bottom
bearing 6g after torque value is achieved.

Fit the Base Interface Assembly
(Pos. 44 or 44a) onto the assembly/
disassembly fixture. Be sure to
use the appropriate spacing plate
that fits snugly t o th e bottom
of the base interface. Using the
incorrect spacing plate can lead to
rotation and end play* problems.

* End play is shaft travel (up and down) through
the chambers.

To reinstall the Neck Ring (Pos. 45),
the Neck Ring Retainer (Pos. 65), or
complete Neck Ring Assembly (Pos.
45a), place these components into
the Chamber (Pos. 4 or 4a) or Base
Interface (Pos. 44). Position the
appropriate neck ring punch

•CR, CRN 32 00SV0025

•CR, CRN 45 00SV0027

•CR, CRN 64 00SV0028

•CR, CRN 90 00SV0029

onto the components to be inserted
into the chamber or base interface.
Using a rubber mallet, drive these
components rmly in place.

To reinstall the Chamber Bearing Ring
(Pos. 47), or Bearing Sleeve (Pos. 47c),
and Bearing Lock Ring (Pos. 47d or 47e),
place the chamber in a downward
position. Depending on the type of
Chamber used (Pos. 3,4a, or 4), place
the appropriate components (Pos.
47 or 47c) and (Pos. 47d or 47e) onto
the chamber. Position the reduced
diameter end of the punch through
the components. Use a rubber mallet
to drive in place.

Reassembly Procedures CR, CRN 32•45•64•90

1

2

6

7

4

5

Place Gardolube (00SV9995) or
equivalent FDA approved non-toxic
lubricant on the threaded area of the
hub. Thread the Split Cone Nut
(Pos. 48) onto the impeller. Using
the split cone nut tool (00SV0004),
Adapter (00SV0403), and Torque
Wrench (00SV0269 ), torque the
split cone nut to 52 ft.-lbs./70 Nm.

3

13

Punch

Refer to the diagrams on pages

22-26 for the appropriate staging

sequence for your particular

model pump. Once the last

chamber has been installed,

continue with step 9.

Hook the Chamber Straps (Pos. 26a)
through the Base Interface (Pos. 44).
Position top end of straps into relieved
area of the Top Chamber (Pos. 3).
Place the Washer (Pos. 26c) and Allen
Screws (Pos. 26b) loosely threaded
into the straps. Allen screws must
be pre-lubricated with Gardolube.
Torque evenly to 11 ft.-lbs./15 Nm.

Remove the holding pin from the

assembly/dis mantl ing fixture.

Lift the STACK® (Pos. 80) out of

the xture. Lay the stack on a at

surface and check the rotation and

end play*. Movement should be

free and without binding.

* End play is shaft travel (up and down)
through the chambers.

10

8

9

14

Reassembly Procedures CR, CRN 32•45•64•90

Place the Was her (Pos. 32) an d
the 5 mm Allen Screw (Pos. 31)
into the suction/discharge base.
Torque the screw to 6ft.-lbs/8Nm.

To install the Bottom Bearing (Pos.
6g) into the Suction/Discharge Base
(Pos. 6), place the bearing into the
hole provided in the base. Ensure
the recessed area of the bearing
is located where the hole for the
allen screw is machined in the base.

Use the bearing punch (00SV0015
or 00SV0212) and a rubber mallet
to drive the bearing into place.

13

11

12

16

15

Place the STACK®
into the suction/
discharge base. Rotate
the straps so they center
between the Staybolts
(Pos. 26) or line u p
with the suction and
discharge ports of the
base. Recheck the shaft
end play (shaft travel up
and down) and the shaft
rotati on. Mov ement
should be free without
bindin g. If bi ndin g
occurs stop, remove
the stack and che ck
clearance between the
bottom shaft bearing,
be ar in g c la mp in g
washer and the bearing
in the base.

Place S leeve (Pos. 55) into t he
su ctio n/dis charg e ba se. P ress
sleev e f irm l y i nt o t he base.

Place the Sleeve O-ring of EPDM or
FKM (Pos. 37) into the recessed groove
in the Pump Head (Pos. 2, 2b, & 2c)
and the suction/discharge base for
standard units. Specialty O-rings in
FXM or FFKM (Pos. 37a) are used in
the lower hot section of the pump in
Cool Top equipped pumps. Lubricate
the O-rings with Rocol (00RM2924)
or Dow Corning 111. Never use oil or
grease as this will attack the O-rings.

14

Replace the four PTFE Stack Compression Spacers (Pos. 60) in the pump head which will seat against the stack. Lubricate the inner bore
of the pump head or all pump heads for Cool Top or Back-to-Back seal equipped pumps. For all models except Back-to-Back units: Lower
the pump head over the Staybolts (Pos. 26). Use a rubber mallet to  rmly seat the pump head in place. Make sure the Priming Vent Plug
(Pos. 18) is inline/over the discharge port of the suction/discharge base.

For Standard and Tandem equipped seal pumps, skip to reassembly step 46.
For Cool Top units, continue with Reassembly steps 18 to 25.
For Back-to-Back units, skip to Reassembly steps 26 to 46 .

17

Reassembly Procedures CR, CRN 32•45•64•90

15

Cool-Top®

Use 00SV2128 and a rubber mallet
to drive in three new Bushings
(Pos. 47g) and the Retainer Ring (Pos.
47h) into the Connecting Pipe (Pos. 149).

Replace the O-rings (Pos. 109a &
109b). Do not roll the O-ring into place;
stretch and release them into the
grooves. Then lubricate the O-rings
with Rocol or Dow Corning 111.

19

18

Lower and seat the Retainer (Pos. 58c) for the connecting pipe. Lubricate the threads
of the 8 mm hex socket Retaining Screws (Pos. 58d) with Gardolube (00SV9995) or
Thread-Eze (96611372). Install and diagonally torque the screws to 46ft.-lbs./62Nm.

21

16

Reassembly Procedures CR, CRN 32•45•64•90

O-rings of EPDM or FKM should have already been installed into the pump heads as
noted in Reassembly, step 14. If they were not, install them now. Then, lower the middle
pump head and carefully press it over the connecting pipe O-ring and seat it on the
spacing ring. Install the upper sleeve, and  rmly press it in place. Put the uppermost
pump head in place, making sure it is  rmly seated. Skip to reassembly step 46.

24

If the upper most Pu mp Head
(Pos. 2b), upper Sleeve (Pos. 55a)
and middle Pump Head (Pos. 2c)
did not leak and were removed as
a complete assembly, then lower it
back in place as a complete assembly
and skip to reassembly step 46. If
the assembly leaked and was fully
dismantled, continue with step 24.

23

Place the Spacing Ring (Pos. 116) onto
the pump head.

22

20

Slide the completed connecting
pi pe assem bly d own o ver th e
shaft and  rmly seat it into the
lowermost Pump Head (Pos. 2).

Reassembly Procedures CR, CRN 32•45•64•90

27

Back-to-Back Seal

Use 00SV2128 and a rubber mallet
to drive in three new Bushings (Pos.
47g) and the Retainer Ring (Pos.47h)
into the Connecting Pipe (Pos. 149).

Replace the O-rings (Pos. 109a &
109b). Do not roll the O-ring into
place; stretch and release them into
the grooves. Then lubricate the
O-rings with Rocol or Dow Corning

111. Once loose, lift the sleeve off.

26

25

17

Assemble the stationary seal by placing the O-ring (Pos. 102) over the Retainer (Pos. 103a). Place the O-ring (Pos. 102a) into the retainer
recess. Lubricate/spray a 5% solution of soapy water onto the O-ring resting in the retainer recess. Align edges of the Stationary Seal
(Pos. 103) with the retainer and  rmly press the stationary seal into O-ring. Stationary seal components can be seen in the diagram on
the next page.

31

Lower the Retainer (Pos. 58c) over the
connecting pipe. Lubricate the threads
of the 8mm hex socket Retaining Screws
(Pos. 58d) with Gardolube (00SV9995)
or Thread-Eze (96611372). Install and
diagonally torque to 46ft.-lbs./62Nm.

28

29

30

Place the Spacing Ring (Pos. 116) onto
the pump head.

Place the complete connecting pipe
assembly into the lowermost Pump
Head (Pos. 2), making sure it is fully
seated.

Lo wer the mid dle Pu mp H ead
(Pos. 2 c) o ve r a nd p as t t he
connecting pipe threads and upper
O-rin g. The pu mp h ead shoul d
rest on top of the spacing ring.

COMPONENTS OF
STATIONARY SEAL

Pos. 103
Upper Seal
Ring

Pos. 102a
O-Ring

Pos. 103a
Retainer
For Upper
Seal Ring

Pos. 102
O-Ring

"N" PUMPS AN D MODEL B

Side View

Side View

Use special tool 00SV7902 to tighten
the nut.

Reassembly Procedures CR, CRN 32•45•64•90

Back-to-Back Seal (continued)

Lu bric ate the inn er surface of
the connecting pipe with Rocol,
Dow Corning 1 11, or soapy
water. Lubricate the threads with
Gardolube or an equivalent FDA
app roved non-tox ic l ubricant .

32

Press the stationary seal assembly
i nt o t h e co nn e ct in g p i pe .
Clean the polished seal face
su rfac e wi th a n al coh ol w ipe.

34

18

Loosely thread the Securing Nut
(Pos. 148) onto the connecting pipe.

36

The order of assembly

for the rotating portion

of the seal can be seen

on the next page.

To prevent leakage,

it is critical to position

the rotating seal

face correctly.

37

When reusing an existing shaft, rst
clean any set screw marks off the shaft
with a light grit emery cloth before
proceeding with the next step. Then,
lift the complete assembly (lowermost
pump head, spacing ring, middle pump
head, and complete stationary seal) by
the lowermost pump head. Make sure
the Priming Vent Plug (Pos. 18) on the
lowermost pump head is inline/over the
discharge port of the suction/discharge
base. Carefully lower the assembly down
the shaft and staybolts. Firmly seat the
assembly in place onto the sleeve.

38

Lower and press the completed
s ta ti on a ry s e al a ss em bl y
i n to t he c on ne ct i ng p ip e .

33

Place the Retaining Washer (Pos. 59a)
onto the seal.

35

Pos. 112
Seal Driver with set
screws, Pos. 113

Pos. 108
Spring

Pos. 106
Cup for O-ring and
Spring

Pos. 107
O-Ring

Pos. 111
Floating Seal Driver

Pos. 104
Rotating Seal Face

(The tapered face should point
upward through the driver 111
and press against the O-ring

107).

LOWER COMPONENTS OF

SEAL ASSEMBLY

COMPONENTS OF ROTATING SEAL

Reassembly Procedures CR, CRN 32•45•64•90

Back-to-Back Seal (continued)

39

With the tapered edge facing upward,
lower the Rotating Seal Face (Pos. 104)
down onto the stationary seal face.

40

Lower the Floating Seal Driver
(Pos. 111) until it fully engages
the rotating seal face. Ensure
the tape r of the r otating s eal
p ro t ru d es th ro ug h d ri v er.

Lower and seat the upper Sleeve
(Pos. 55a) into the middle pump head.

44

43

45

Lower and rmly seat the uppermost
Pump Head (Pos. 2 b) onto the
upper sleeve. Proceed to step 46.

19

41

Lubricate the inner surface of the
O-ring (Pos. 107) with Rocol, Dow
Corning 111, or soapy water. Slide the
O-ring down the shaft until it contacts
both the driver and the protruding
su rfac e of r otatin g sea l fa ce.

42

Lower the

Cup (Pos. 106)

over the O-ring.

Lower the

Spring

(Pos. 108) until

it ts over the

cup.

Lower the Driver

(Pos. 112) with

set screws
(Pos. 113).

Driving tabs

should pass and

engage each

other. With the

shaft and the

seal drivers

pushed down as

far as possible,

tighten the

3mm Set Screws

(Pos. 113) to

10ft.-lbs./13Nm.

Lub ricate the t hrea ds o f the
8 mm hex socket Retaining Screws
(P os. 58d ) with Gard olub e or
Thread-Eze. Install and diagonally
to rq ue t o 4 6f t.- lb s. /6 2N m .

Reassembly Procedures CR, CRN 32•45•64•90

When reusing an existing shaft,
and if the shaft has not already
been cleaned, fi rst clean away any
set screw marks off of the shaft
with a light grit emery cloth before
proceeding with the next step.

47

Evenly tighten and then torque
the th ree 3 mm set screws to
6 ft.-lbs./8Nm.

20

Pushing against the drive collar,
slide the tandem seal assembly
do wn the shaft u nti l it sto ps
aga inst the lowe r shaf t seal.

Evenly tighten and then torque the
three 3 mm set screws to 6 ft.-lbs./8Nm.

Lubricate the inner surface of the
lower O-ring of the Shaft Seal (Pos. 105)
with Rocol, Dow Corning 111, or soapy
water. Slide the seal down the shaft by
pushing against the the drive collar of
the seal. Seat the seal fi rmly in place.
For Tandem Seal equipped pumps only,
continue with step 49. All other
pump types: Standard, Cool Top, and
Back-to- Back units, skip to step 55.

48

Apply Rocol or

Dow Corning

111 to the

groove in the

housing of the

Tandem Seal

(Pos. 105c).

Place the

O-ring

(Pos. 109) into

the groove of

the tandem

seal housing.

46

Slide the Washers (Pos.66a) over
the Staybolts (Pos. 26). Lubricate
the threads of the staybolts with
Gardolube (00SV9995) or Thread-Eze
(96611372). Thread the Staybolt
Nuts (Pos. 36) onto the staybolts.
Diagonally torque the staybolt nuts to
74ft.-lbs/100Nm.

49

Tandem Seal

50

Tandem Seal

51

Tandem Seal

Tandem Seal

52

53

Tandem Seal

54

Tandem Seal

Lift the shaft upward and place the
Adjust Fork/Spacing Tool, 985924,
between the housing and seal driver
ring.

Tandem Seal continues with step 58.

The motor, motor stool, and/or bearing  ange
will be assembled as a complete unit. Place
the entire assembly onto the pump head.
Lubricate the threads on the 8 mm hex socket
Retaining Screws (Pos. 28) with Gardolube or
Thread-Eze. Install and diagonally torque to
46ft.-lbs./62Nm. If the motor was removed
during disassembly, reattach the motor.
Lubricate the threads of the Motor Bolts (Pos.
28a) and then tighten the bolts diagonally to:

30 ft.- lbs./41 Nm for 1/2" x 13 UNC, 3-40 HP
59 ft.- lbs./80 Nm for 5/8" x 11 UNC, 50-60 HP

To install the Couplin g Halves
(Pos. 10a), position the coupling
half relief area flushed with the
top of the shaft as shown in the
diagram. Lubricate the threads on
the 8 mm hex socket Coupling Screws
(Pos. 9) with Gardolube or Thread-Eze.
Loosely thread the screws in place.

Reassembly Procedures CR, CRN 32•45•64•90

Push the shaft downward (for Back-to­Back units, continue downward pressure
as the inboard seal spring tension may lift
the shaft). Evenly tighten, then torque the
three 3 mm set screws to 6 ft.-lbs./8Nm.

Pl ace a s econ d ad jus tin g fork
on top of the seal collar. Install
the Coupling Halves (Pos. 10a).
Lub rica te the thre ads on the
8 mm hex socket Coupling Screws
(Pos. 9) with Gardolube or Thread-Eze.
Loosely thread the screws in place.

Torque the 8 mm hex socket coupling
screws to 63 ft.-lbs./85Nm. This step
is the same for all pump types (in the
photo a tandem seal version is shown).

61

Li ft t he s ha ft an d i nse rt th e
adjusting fork under the seal collar.

Lo we r an d se at th e Ret ai ner
(Pos. 58). Lubricate the threads of
the 8 mm hex sock et Re taini ng
Screws (Pos . 58a) w ith Gardolube
or Thread-Eze. Install and diagonally
torque the screws to 46ft.-lbs./62Nm.

62

Make sure the gaps on both sides of
the coupling are even. Applies to all

pump types.

Attach the motor and motor stool separately
to the pump head. Lubricate the threads
on the 8 mm hex socket Retaining Screws
(Pos. 2 8) with G ardolube or T hread­Eze. Install and diagonally torque to
46f t.-lb s./62N m. P lace the moto r
ont o t he mo to r s to ol , lub ri ca te
the t hr ea ds of t he M ot or B ol ts
(Pos. 28a) and tighten the bolts diagonally to
30 ft.-lbs./41Nm.

58

Placement of the
Motor Stool (Pos. 1a)
differs depending on

model size.

15 HP

and up

3 - 10 HP

and Up

Tandem Seal Only

59

Standard, Cool Top®, &

Back-to-Back Seal Units

60

21

Standard, Cool Top®, & Back-to-Back Seal Units

56

57

55

ALL PUMP TYPES

Reassembly Procedures CR, CRN 32•45•64•90

For storage, place the adjusting fork around
one of the seal holder allen screws. Check
rotation by turning the coupling by hand. If
the shaft is tight or will not rotate, disassemble
and begin the assembly procedure again.

22

Remove the adjusting forks

Fit Coupling Guard (Pos. 7) over screws
(Pos. 7a). Torque to 6 ft.-lbs./8Nm.

Remove the adjusting fork.

For storage, place the adjusting
forks around two of the seal
retaining screws. Check rotation
by turning the coupling by hand.
If the shaft is tight or will not
rotate, disassemble and begin
the assembly procedure again.

Instal l s y s tem p ip ing to
th e ta ndem seal ho usi ng.

Fit the coupling guard and
scr ews. To rque s crew s t o
6 ft.-lbs./8Nm.

Tandem Seal

66

6867

69

63

64

65

Standard, Cool Top®, & Back-to-Back Seal Units

THE PUMP IS

NOW COMPLETELY

REASSEMBLED.

Return the pump to the system and install it following the Installation and Operation instructions.
If the unit was not removed from the system, open the isolation valves in the system piping to fully
vent the pump. Con rm proper electrical connections before restoring power supply.

Legend

CR, CRN 32

Order of Stage Assembly

Reassembly Procedures CR, CRN 32•45•64•90

23

Low NPSH
Combination
Replacement

Start for Low NPSH
order *

Low NPSH
Combination
Replacement

*Low NPSH units start with 2-1 and continue
to the 14 stage.

NOTE: Refer to Parts List for ALL position
descriptions.

Legend

CR, CRN 45

Order of Stage Assembly

Reassembly Procedures CR, CRN 32•45•64•90

24

Low NPSH
Combination
Replacement

Start for Low NPSH
order *

Low NPSH
Combination
Replacement

*Low NPSH units start with 2-1 and continue
to the 10 stage.

NOTE: Refer to Parts List for ALL position
descriptions.

Legend

CR, CRN 64

Order of Stage Assembly

Reassembly Procedures CR, CRN 32•45•64•90

25

Low NPSH
Combination
Replacement

Start for Low NPSH
order *

Low NPSH
Combination
Replacement

*Low NPSH units start with 2-1 and continue
to the 7-1 stage.

NOTE: Refer to Parts List for ALL position
descriptions.

Legend

CR, CRN 90

Order of Stage Assembly

L-CR-SM-010 Rev. 04/10

PRINTED IN USA

Being responsible is our foundation

Thinking ahead makes it possible

Innovation is the essence

GRUNDFOS Pumps Corporation

17100 W. 118th Terrace
Olathe, Kansas 66062
Phone: [phone]
Fax: [phone]

www.grundfos.com

GRUNDFOS Canada, Inc.

2941 Brighton Road
Oakville, Ontario L6H 6C9 Canada
Phone: [phone]
Fax: [phone]

Bombas GRUNDFOS de Mexico S.A. de C.V.

Boulevard TLC No. 15
Parque Industrial Stiva Aeropuerto
Apodaca, N.L. Mexico 66600
Phone: [phone]
Fax: [phone]

26

Low NPSH
Combination
Replacement

Start for Low NPSH
order *

Low NPSH
Combination
Replacement

*Low NPSH units start with 2-1 and continue
to the 6 stage.

NOTE: Refer to Parts List for ALL position
descriptions.