C.E. Niehoff & Co. N1240-2-3, N1243-2-6 Instructions

N1240-2/3 and N1243-2 Alt. with N3218 Regulator

N1243-6 Alt. with N3271 Regulator

Installation Instructions

This symbol is used to indicate

CAUTION

presence of hazards that can cause
minor property damage.

Install alternator as shown in Figure 1:

Slip bushing located in rear mounting

CAUTION

foot must be securely tightened against
alternator mounting bracket on engine.
Failure to do so can result in broken
mounting feet or broken upper mounting

bracket.

M20x1.5 Nut

torque to 163 Nm/120 lb.ft.

Belleville washer

M12x1.75 Mounting bolt –

torque to 61 Nm/45 lb. ft.

Hardened washer







1. Units are shipped with pulley, belleville washer, and
nut. Check torque on locknut for 163 Nm/ 120 lb. ft.

2. Use hardened washers between aluminum surfaces
and bolt heads and nuts. Torque mounting bolts to
88 Nm/65 lb. ft.

3. All cabling, wiring or conduit must be supported
within 305 mm/12 in. of termination on alternator.

4. Choose wire gauge for B+ and B– cables capable of
handling maximum alternator output with minimum
voltage drop.

Regulator IGN terminal;

torque to 4.5 Nm/40 lb. in.

B+ terminal

(on reverse side of control unit)

M12x1.75 Bolt –

torque to 32 Nm/24 lb. ft.

Vehicle harness

connection











M12/0.50 in.

mounting bolt

(full length)

Hardened

washer

Alternator

mounting

bracket

on engine







Bracket

on engine







Slip bushing must be tightened against
bracket — see “CAUTION” above

B– terminal

M10x1.5 Bolt –

torque to 15 Nm/11 lb. ft.

M12/0.50 in. Locknut –

torque to

88 Nm/65 lb. ft.

Hardened washer

Figure 1 - Alternator Installation Details

C. E. Niehoff & Co. • 2021 Lee Street • Evanston, IL 60202 Tech Services Hotline [phone]

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