C.E. Niehoff & Co. C621 Instructions

C621

Drive End (DE) or

Anti-drive End (ADE) Stator

Replacement Instructions

C621 alternator has a special

CAUTION

splice connecting the Y leads
between the ADE and DE stators
which must be handled carefully
for the stators to function prop­ erly after replacement.

The steps in this instruction sheet
replace the corresponding steps
in the CEN 600 Series Service
Manual SM6.

Before replacing stator, verify

NOTICE

that the correct replacement
stator is used. See additional
instructions provided with
stator.

If replacing DE stator, only DE

NOTICE

stator should be removed.
If replacing ADE stator, both
stators should be removed.

Section E in CEN 600 Series Service Manual
SM6:

14. Remove ADE and DE Stators
(See Figure E-7)

a. Ensure scribe marks are visible on DE and

ADE edges of shell where tabs are missing
on DE and ADE stators.

b. Remove long nuts securing through-studs.

Remove through-studs.

c. Cut the middle of interconnect splice holding Y

leads to separate the stator connections.

d. Arrange CEN A10–132 field coil/stator tool.

e. Press DE stator out of shell.

Do not damage phase
leads when removing
stators from shell.

f. If replacing ADE stator, rearrange tool and

press ADE stator from shell.

CAUTION

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Interconnect splice

First press out
DE stator
from shell

Then press out
ADE stator
from shell

Figure E–7 Removing Stators

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Section F in CEN 600 Series Service Manual
SM6:

If replacing ADE stator or both

NOTICE

stators, start with step 2a.
If replacing DE stator only, start
with step 2d.

2. Install new ADE Stator or both new ADE/
DE Stators

CAUTION

when inserting stators in shell.

a. Set new ADE stator (longer phase leads face

down) on ADE edge of shell. Align scribe mark
on shell where tab is missing on ADE stator.
Arrange CEN A10–136 stator insertion tool on
stator. See Figure F–1a.

b. Press new ADE stator into position using a

spray lubricant if necessary. Make sure the
stator stops on the ledge inside the shell.
See Figure F–1a.

c. From the anti-drive end, insert 6 insertion

studs provided with CEN A10-136 stator inser­ tion tool into new ADE stator. See Figure F–1b.

Do not damage phase leads

A10–136
stator
insertion
tool

ADE stator

Ledge inside shell

Original
scribe
mark
on shell

Missing
tab on
ADE stator

Figure F–1a ADE Stator Assembly

Stator
insertion
studs (6)

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Figure F–1b Stator Insertion Studs

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d. Turn shell so drive end is up. To properly

position DE stator inside shell (see Figure F–1c):

1) Coil longer ADE stator leads inside ADE stator.

2) Align scribe mark on shell with missing tab
on DE stator. Align 6 insertion studs with
holes in DE stator.

3) Arrange CEN A10–136 stator insertion tool
on DE stator.

e. Press DE stator i n place. Insertion studs shou ld

enter holes in DE stator. Make sure DE stator
stops on ledge inside shell. See Figure F–1c.
Remove 6 insertion studs.

Do not use insertion
studs in place of through­ studs in fi nal assembly.

f. On DE stator, remove stator wedges from open-

ings where A DE stator leads and field coil lead s
will pass between DE stator windings. See Fig­ ure F–1c for locations of DE stator phase leads
and ADE stator phase leads as arranged in
stator windings.

g. Insert ADE stator phase leads between openings

in DE stator.

Do not damage phase
leads when threading
leads through openings.

h. Insert through-studs from anti-drive end.

See Figure F–1d.

i. Use locknuts to secure through-studs on drive

end of shell. See Figure F–1d. Hex flat on screw­ head must be parallel to winding. Use a suitable
adhesive such as Loctite
Follow manufacturer’s instructions. Torque nuts
on drive end to 4.5 Nm/40 lb. in.

CAUTION

CAUTION

®

222 on threads.

Scribe mark on DE of shell

Scribe mark on
ADE of shell

Phase Lead and Field Coil Lead Orientation—C621

A10–136
stator
insertion
tool

DE stator

Insertion
studs (6)–
not for fi nal
assembly

Ledge inside shell

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Figure F–1c DE Stator Assembly

Long nuts

Through-stud

Figure F–1d Through-stud Assembly

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j. Reconnect stators with interconnect splice:

1) Slide new sleeve over end of DE or ADE lead.

2) Crimp new connector socket on the DE
stator Y lead. Crimp new connector pin on
the ADE stator Y lead. Securely mate the
connectors.

3) Apply hi-temp solder over mated connection.

4) Completely cover mated connection with
Dow Corning
equivalent—wait until coating has hardened
to ensure waterproofness.

5) Position new sleeve over sealed connection.

6) Position spliced Y leads against wall of shell
so that field coil can fit into space between
stators wit hout damagi ng interconnect splice
or Y leads.

®

SE 9186L RTV coating or

Return to CEN 600 Series Service Manual SM6

to fi nish C621 alternator assembly

Connector
socket

Sleeve

Connector pin

Interconnect
splice

Figure F–1e Interconnect Splice Assembly

If you have questions about your a lternator or any of these instruct ions, or if you need to locate a Factory Authorized Service Dealer, please contact us at:

C. E. Niehoff & Co.• 2021 Lee Street • Evanston, IL 60202 USA

Page 4 of 4

TEL: [phone] USA and Canada • TEL: [phone] outside USA and Canada • FAX: [phone]

E-mail us at [e-mail]

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