How to Replace an Alternator on a 2000 Chevy Blazerby Grace MclainUpdated November 07, 2017
Items you will need
3/8 inch ratchet
3/8 inch drive socket set
The alternator on the 2000 Chevy Blazer is the main source for the vehicle's charging system. The alternator regulates the voltage to the battery and controls all of the electrical components on the Blazer. The serpentine belt, which is run by the crankshaft pulley, controls the alternator itself. Every time the crankshaft pulley turns, the alternator pulley also turns.
Pull the 2000 Chevy Blazer into a safe working area and shut off the engine. Open the hood and locate the battery on the driver side front of the engine.
Remove the negative battery cable from the battery with the adjustable wrench. Turn the negative battery cable bolt counterclockwise to loosen and remove the cable.
Locate the serpentine belt tensioner directly below the alternator. The tensioner has a pulley on one end that releases the tension from the serpentine belt so that you can remove the belt from the alternator pulley.
Release the tension from the serpentine belt tensioner by turning the bolt head in the center of the tensioner counterclockwise with the 3/8 inch drive ratchet and a socket.
Remove the belt from the alternator pulley with your other hand while you release the tension off of the belt.
Unplug the electrical wiring harness that plugged in to the rear of the alternator. Unscrew the positive battery connection on the rear of the alternator with the 3/8 inch drive ratchet and a socket.
Locate the three bolts connecting the alternator to the alternator bracket. There are two bolts on the front of the alternator and one bolt in the rear of the alternator. Use the 3/8 inch drive ratchet and a socket to turn these three bolts counterclockwise to loosen and remove the bolts.
Slide the pry bar between the alternator and the bottom of the alternator bracket. Pry the alternator upward until the alternator comes out of the bracket. Remove the alternator from the engine compartment.
Slide the new alternator into the bracket and match the three bolt holes up. Screw the two front bolts and the rear bolt back into the alternator. Tighten the bolts down tight with the 3/8 inch drive ratchet and socket.
Slide the positive battery connection back on the rear of the alternator. Screw the nut over the connection and tighten the positive battery connection with the 3/8 inch drive ratchet and socket.
Plug the electrical wiring connector back into the rear of the alternator by pushing the connector into the socket on the back of the alternator.
Turn the belt tensioner counterclockwise again and slide the belt back over the alternator pulley. Release the tensioner so that the belt will tighten onto the alternator pulley.
Screw the negative battery cable back on the battery and tighten down with the adjustable wrench.
Crank the engine and let the engine run for about five minutes so that the new alternator can completely charge the system. Turn the engine off.
Make sure that the serpentine belt stays on the other pulleys while removing the belt from the alternator pulley. If the belt does come off the other pulleys, use the serpentine belt routing diagram that is on top of the fan shroud to reroute the belt around the pulleys.
Always wear safety glasses when working around the battery.
- Haynes Repair Manual; Chevrolet S-10 & GMC Sonoma Pick-ups Haynes Repair Manual for 1994 thru 2004. Includes 1995 thru 2004 S-10 Blazer & GMC Jimmy, GMC Envoy 1998 thru 2001 and 1996 thru 2001 Oldsmobile Bravada & Isuzu Hombre"; John Haynes-2005
- Tim Boyle/Getty Images News/Getty Images