The Ford Fiesta model cars have a alternator that is responsible for supplying power to the vehicle's electrical system and for keeping the battery fully charged. The alternator on the 1977 to 1981 model Fiestas has an adjustment bracket on top of the alternator that keeps the alternator belt tensioned at all times. Replace the alternator immediately if the alternator begins to malfunction or it stops working. Once the alternator quits working, the battery will go dead and the entire electrical system will stop working.
Drive the Ford Fiesta to a safe working environment. Push the parking brake in and open the bonnet.
Secure the hood in place with the lock rod. Then, remove the battery cable from the negative post of the battery with an adjustable wrench. Pull the negative battery cable back out of the way of the negative battery post. Then, close the bonnet.
Loosen all of the lug nuts from the driver side front wheel with the lug wrench.
Slide the floor jack under the front of the Ford Fiesta and jack the front end up from a safe jacking point. Once the Fiesta is high enough, place the safety stand under the driver side frame rail near the front wheel compartment. Slowly lower the car onto the top of the stand. Leave the floor jack in the up position under the frame rail.
Remove the lug nuts from the wheel. Then, pull the wheel off and place it on the ground flat so that it does not roll.
Remove the plastic cover in the rear of the wheel compartment by unscrewing the small bolts with the ratchet and a socket. Pull the cover out and place it on the ground. The alternator and the adjustment bracket can now be accessed.
Loosen the locknut on the front of the alternator adjustment bracket with the ratchet and a socket. Then, turn the adjustment bolt at the end of the bracket counterclockwise to loosen the drive belt around the alternator pulley. Pull the belt out of the alternator pulley and let it hang down.
Remove the positive battery connection from the back of the alternator by unscrewing the locking nut with a ratchet and a socket. Then, pull the wire off of the stud and away from the alternator.
Unplug the wiring harness connector from the back of the alternator by pressing inward on the plastic clips near the front of the plug. Pull out on the plug at the same time and the plug will come out of the back of the alternator.
Loosen and remove the alternator mounting bolts with the ratchet and a socket. There are three pivot bolts that connect the alternator to the alternator bracket. One pivot bolt is at the top of the alternator and the other two pivot bolts are located on the bottom of the alternator. All three pivot bolts can be accessed and removed from the bottom of the wheel compartment.
Wiggle the alternator back and forth with your hands until the alternator is loose inside of the alternator bracket. Then, pull the alternator out of the bracket and out through the wheel compartment.
Slide the new alternator through the wheel compartment and into the alternator bracket.
Reverse the same steps above to hook the alternator back up and install the drive belt back across the alternator pulley When finished installing the new alternator, reinstall the plastic cover and the wheel. Tighten the lug nuts onto the wheel with the lug wrench. Jack the front end of the Ford Fiesta back up and remove the stand. Lower the Fiesta back to the ground and remove the floor jack.
Open the bonnet back up and put the negative battery cable back onto the battery and tighten with the ratchet and socket. Crank the engine and let it run for approximately one minute so that the new alternator can fully charge the battery. Then, turn the engine off and close the bonnet.
If the alternator is tight inside of the alternator bracket after all of the pivot bolts have been removed, use a small pry bar to pry the alternator free from the bracket.
Use extreme caution when working under the front of the Ford Fiesta when it is on the safety stand.