2012 Buick Lacrosse Serpentine Belt Diagram (2024)

FAQs

How do you find a serpentine belt routing diagram? ›

Vehicle manufacturers produce serpentine belt diagrams that are designed to aid with this task. Some vehicles have the serpentine belt diagram located on a decal somewhere in the engine compartment.

A: Commonly a belt routing diagram sticker is on the underside of the hood or in the engine compartment. If there is no diagram, make a sketch of the belt and pulleys before removing the belt.

To replace the Serpentine Belt on this vehicle will require the use of a special tool: Hydraulic Belt Tensioner Compressor.

Turn off the engine and remove the serpentine belt. Shake and spin each pulley to check if there is excessive play or noise. Any play or back-and-forth movement indicates a bad pulley bearing.

This industry standard number, frequently denoted as the “PK” number, is printed next to the manufacturer's part number on almost every serpentine belt produced, and can be seen in the examples below. WHAT IS A “PK” NUMBER? A “PK” number is a worldwide standard metric belt measurement printed on most serpentine belts.

There are two ways to align pulleys: Traditional and laser. Traditional alignment methods are quick but often inaccurate. With these methods, mechanical tools such as straightedges, tape measures, wire, string, feeler gauges, spirit levels and calibrated cones are used.

If the belt is already out of place, locate the driver's manual or the under-the-hood placard, where you'll find a sketch of the routing.

Check if the belt runs centrally on the pulleys. Any sideward movement or slippage can indicate misalignment. Straightedge or String Line: Place a straightedge or taut string along the faces of the pulleys to see if they line up perfectly. Any deviation from a straight line suggests angular or parallel misalignment.

To do this, the belt has to be twisted 90 degrees. Twist it one way, and drive it from the appropriate side, and it'll go one way; twist it the other way, so you can drive it from t'other side, and it will go in the opposite direction.

Serpentine belt and its purpose

The serpentine belt is a single, continuous belt that drives multiple components like the alternator, power steering pump, water pump, and of course, the air conditioning compressor.

How do I know which serpentine belt to buy? ›

You can find the correct size of serpentine belt for your car in the owner's manual or by using an online belt sizing tool. If you are unsure about the size of the serpentine belt you need, it is best to consult a mechanic or an auto parts store.

Common symptoms of a malfunctioning idler pulley include corrosion on the pulley's surface, chattering and squealing noises, and slow spinning. Recommended idler pulley brands include Replacement, Gates, and Dayco.

You can replace only the pulley, or you can buy a new tensioner with a new pulley attached, or you can buy a kit with a new belt, tensioner/pulley, and idler pulley if there is one, and do it all.

Most vehicles nowadays usually have a belt routing sticker located somewhere in the engine compartment, making it even easier.

If the belt is already out of place, locate the driver's manual or the under-the-hood placard, where you'll find a sketch of the routing.

The tensioner pulley is responsible for keeping the belt tense while making sure it stays aligned the entire time you're driving. While the location of the tensioner pulley can vary depending on the vehicle, you can usually find it at the end of the tensioner, which is typically connected to the accessory drive belt.