
Replace Alternator
How to Replace an Alternator
An alternator is an important
electrical component. It produces and electrical current when a magnetic field around
a conductor changes (spins). Typically, a rotating magnet, called the armature,
turns within a stationary set of conductors wound in coils on an iron core, called
the stator. The field cuts across the stationary conductors, generating an electro
magnetic field and producing an alternating current (AC). To regulate the amount
of power produced, the electrical flow is regulated by a voltage regulator. This
eliminates overcharging of the battery
and burning up electrical components. In general, the alternator is responsible
for recharging the car’s battery and running electrical components when the engine
is running.
Without an operational alternator, the car’s battery will slowly drain
until the car will no longer start. If your battery light comes on or the alternator
gauge drops below 12 volts with the
engine running, chances are
the alternator is going bad. However, if the alternator shows a charge higher than
approximately 14 volts, chances are the regulator isn’t doing its job which can
result in an overcharged battery, electrical component damage, and burnt wires.
There are safety devices in place in the event of a short circuit. A wire, called
a fusible link, functions as a heavy duty
fuse. If a short circuit occurs,
the fusible link will burn up, protecting the
electrical system. The
fusible link is a wire that most people over look.
What often happens is the battery
will test good and the alternator will produce power; however, the battery will
continue to drain and go dead due to the lack of amperage delivered to the battery.
When the fusible link is completely severed, the connection between the battery
and the alternator is lost. Thus, the battery can not be charged and will slowly
die. Common symptoms include dim lights, slow wipers, slow blower motor. Basically,
anything related to the electrical system will be affected. Before replacing an
alternator be sure to test the
alternator to make sure it is the problem other than the battery.
Park your car on level ground with the engine off and the emergency brake on.
Always raise a car according to the manufacturers recommended instructions and secure
with jack stands if needed. Also we will be dealing with a small amount of grease
so be sure to wear protective clothing, eyewear and gloves.
Tools and Supplies to Complete this Job
1. Wrench set
2. Sockets and ratchet set
3. Screwdriver set. (to disconnect wiring clips on some vehicles)
4. Shop towels
5. Replacement alternator
6. Volt meter (optional)
Directions
Step 1 - Park the vehicle in work area and allow it to cool.
Step 2 - Disconnect the negative battery
cable.
Step 3 - Locate the serpentine belt automatic tension pulley.
Step 4 - Using a wrench, turn the
belt tension pulley
to create slack in the belt and simply slide the belt off the pulley.
Step 5 - On the rear of the alternator, you will find wiring. Carefully unplug
or unbolt the wiring from the rear of the alternator. (note: don't worry if you
cannot see or access the wiring, you will be able to disconnect the wiring later
in the removal).
Step 6 - Loosen and remove all mounting bolts securing the alternator to the
mounting bracket.
Step 7 - Once all bolts are removed, slide the alternator out and away from the
mounting bracket.
Step 8 - Match the old alternator to the replacement unit especially the wiring
plugs or connectors.
If further assistance is needed, our certified car repair technicians are ready
to answer your car questions. Also, gain manufacturer
specific instructions and information by clicking -
Auto Repair Manual
Related Car Repair Information