# What do numbers on serpentine belt mean?

## What do numbers on serpentine belt mean?

Most v-ribbed belts, commonly referred to as serpentine belts, contain two different part numbers. EXAMPLE: 6PK1003 » 6 – This indicates the number of ribs on the belt; therefore, this is a 6-rib belt. » PK – The “P” indicates a metric designation, and the “K” indicates the belt is automotive per SAE J1459.

### How do you read the serpentine belt numbers?

Read the number that follows the letter. This number represents the length of the inside of the fan belt (as opposed to the number in the standard automotive belt, which represents the outside circumference). For example, if the number is 46, that means the inside circumference of the belt is 46 inches.

How do you read V belt part numbers?

The number following it is the outside length of the belt in tenths of inches. The inside length of the belt is typically 2″ less for a 4L belt, and 1-1/2″ less for a 3L belt. An example would be 4L460, which would be 46″ long outside, 44″ inside.

What happens if serpentine belt is put on wrong?

In some instances it may be possible to install a serpentine belt the wrong way. If this happens, one or more pulleys will rotate in the WRONG direction, affecting the operation of the alternator, water pump, A/C compressor or power steering pump. This can cause major problems.

## What does FR mean on a timing belt?

FR is front of engine, should be facing away from engine toward passenger fender.

### How do you identify if the serpentine belt is in good condition or need to replace?

It is a good idea to physically inspect your serpentine belt from time to time. Check for cracks, chunks missing, abrasions, rib separation, uneven rib wear, and damaged ribs. If you notice any of these, it is time to replace your serpentine/drive belt.

How often should a serpentine belt be replaced?

And they’re crucial for running everything from alternators to power steering. In other words, when it’s time to replace it, replace it. Serpentine belts will last you a few years, but depending on whom you ask, you’ll need to start thinking about checking it every 50,000 to 60,000 miles.

Where is the serpentine belt on a car?

Your vehicle’s serpentine belt is one long, winding belt that snakes around several pulleys and is usually visible at the front or on the side of the engine. In most modern vehicles, it drives the air conditioning, power steering, water pump, and alternator – charging the battery and providing additional electrical power.

## How is the tension set on a serpentine belt?

Depending on the application, your serpentine belt will either have tension placed on it using a movable bracket or an auto tensioner pulley. This pulley uses an internal spring to apply consistent pressure to the belt at all times. If your vehicle does not have a tensioner pulley, the alternator bracket is likely how tension is set on the belt.

### Can a loose serpentine belt cause an alternator to whine?

If the belt is too loose to maintain grip on the alternator pulley, you may experience a similar symptom as a snapped belt. If you start to notice a whine from the engine that changes with engine speed, you may want to have the tension of the serpentine belt double checked.