Replacing Your Alternator Pulley: A Quick, Jolt-Free Guide
Your alternator produces electricity for your vehicle—power that you need for everything from turning on your dome lights to starting your car. Your alternator does this by using a rotating pulley, which is driven by either a single belt, or a serpentine belt. This pulley can rotate at speeds up to 18,000 revolutions per minute. As with anything that moves repeatedly at high speeds, your alternator pulley can get worn out in time. When that happens, you should replace it right away. With the some basic tools and one special tool, you can save some cash in repairs by doing it yourself.
Difficulty Level: Moderate
Here's what you'll need:
- Alternator pulley puller
- Socket wrench set (must include a 3/8-inch ratchet)
- Pry bar
- Replacement alternator pulley
- Vehicle owner manual
And here are the steps:
- Open the hood of your vehicle and use your wrench to disconnect the negative battery cable from the battery terminal.
- Use the appropriate wrench to loosen belt tension bolt on your alternator.
- Push the alternator assembly with the pry bar so that the belt becomes loose enough to slip over the pulley and remove.
- You should find four pulley attachment bolts—remove them with your 3/8-inch ratchet.
- Take your alternator pulley puller. You will find four holes at the of each of its legs. Line those up with the bolt holes on the pulley. Screw them in by hand until they are tight enough.
- Use your ratchet and a socket to tighten the pulley bolts.
- Turn the shaft knob on your alternator pulley puller. Keep turning until the alternator pulley slides out from the shaft.
- Install your replacement alternator pulley by following the reverse order of disassembly.
Remember not to lose any components (nuts, bolts, etc.) in the process of removing the old alternator pulley. You will need those same components in installing your replacement pulley in exactly the same way as the old one. Make sure you don't over-tighten the pulley bolts as this will damage the threads. Refer to your vehicle owner manual for specifications (such as the location of your alternator and the kind of mounting bolts needed) that may require you to deviate from these general instructions.