Delco Remy 31SI Installation Instructions

The 31SI Alternators have Remote Sense Technology that is highly recommended for improved Battery Monitoring
and Charging Performance.
Remote Sense Technology senses the voltage level at the batteries or similar location where battery system voltage can be
read and adjusts alternator output accordingly. A direct connection from the alternator's remote sense terminal to the
batteries provides highly accurate voltage readings and optimizes state of charge.

Typical Alternator Battery Charge

Circuit without a Remote Sense
line is only 14.0 volts, with normal voltage
drops in the circuit.
Alternator Battery Charge Circuit
with a Remote Sense line is 14.5
Volts. Voltage is always adjusted to
specific battery requirements.
If the Remote Sense Line is not connected to the Remote Sense Terminal, the alternator will regulate at a voltage above the
external sense setting to compensate for the voltage drop between the alternator output terminal and the batteries.
WARNING!!!!ALWAYS USE PROPER EYE PROTECTION WHEN PERFORMING ANY MECHANICAL REPAIRS TO A
VEHICLE – INCLUDING, BUT NOT LIMITED TO, ANY INSTALLATION AND OR REPAIRS TO THE DELCO REMY
ALTERNATORS. FAILURE TO USE PROPER EYE PROTECTION CAN LEAD TO SERIOUS AND PERMANENT EYE
DAMAGE.
Only perform the mechanical functions that you are properly qualified to perform. A professional installation specialist should
handle mechanical repairs that are beyond your technical capabilities.

DANGER!!!

To avoid injury or damage, always disconnect the negative cable at the battery before removing or replacing the
alternator. The alternator output terminal is always live ("hot"). If the battery is not disconnected, a tool accidentally touching
this terminal and ground can quickly get hot enough to burn skin or damage to the tools and surrounding parts.
FOLLOW ENGINE OR VEHICLE MANUFACTURER'S INSTRUCTIONS FOR REMOVING THE OLD ALTERNATOR
FROM THE ENGINE AND INSTALLING THE NEW ALTERNATOR.
PULLEY INSTRUCTIONS: Use pulley from old alternator if this alternator does not have a pulley or pulley supplied is
different from the one on alternator being replaced. NOTICE! When changing the pulley, keep the alternator in the
horizontal position and do not apply any pressure to end of the shaft. Internal damage will occur if the shaft is
pushed back and turned. If there were spacers, when the fan and pulley were
removed, make sure all spacers are replaced when installing fan and pulley on this
alternator. Hold the shaft by placing an 8.01 mm (5/16") hex wrench in the hexagonal
hole in the shaft while removing or installing the pulley. Tighten the pulley nut to
95-108 Nm (70-80 lb ft).
BELT TENSIONING INSTRUCTIONS: Improper belt tension can cause premature
alternator failure. If the belt must be tightened manually, place a wood block
between the alternator and pry bar (See illustration). Pry as close to the center of
the unit as possible. Use a torque wrench to tighten mounting bolts to specified
torque. Follow vehicle or engine manufacturer's specifications carefully for belt
tension and mounting bolts torque. DO NOT OVER TIGHTEN BELT!
INSTALLATION INSTRUCTIONS (See illustration, page 2):

Disconnect the negative (-) cable at the batteries.

Identify and tag all leads when removing the old Alternator and install them on the same terminals of the new 31SI
Alternator.
NOTICE - Only licensed Remy Inc. product and component parts should be used, and the use of other parts or modifications not approved by Remy Inc.
will void all applicable warranties. The failure to carefully follow these Installation Instructions, set forth above, will void all applicable warranties.
Delco Remy Ⓡ is a registered trademark of General Motors Corporation, licensed to Remy Inc., Pendleton, IN 46064.
© 2008 Remy Inc.

31SI ALTERNATOR INSTALLATION INSTRUCTIONS

1 10513666
INSTRUCTION SHEET
10513666
12SE08 C/P16954 REV 1
14.5 Alternator Volts
- .2 Voltage Drop
- .3 Voltage Drop
14.0 Volts Sensed
at Alternator
+.5 Voltage Adjustment
with sense Line
14.5 Charge Voltage