How to Replace a Belt on a 1999 300M

The 1999 Chrysler 300M was a sports sedan that was built between 1999 and 2004. The 1999 300M came fitted with a 3.5 liter V-6 engine that produced close to 250 horsepower. The engine has two accessory belts that operate each vehicle's accessories, one a V-belt and the other a serpentine belt. Both are adjusted by an adjustable pulley. Use the idler pulleys to loosen, replace and tighten the belts. Change the belts at the first sign of any type of damage.

Instructions

1

Park the 1999 Chrysler 300M and shut the engine off. Set the parking brake and open the hood. Wait for the engine to cool before working in the engine area.

2

Locate the belt routing diagram on top of the fan shroud. The diagram pictures the belts being properly routed around the accessory pulleys. Use the diagram when installing the new belt. If the diagram is missing, draw out your own diagram with a pen and a notepad by looking at the routing direction of the belt as it is routed around the pulleys.

3

Locate the serpentine belt adjustable idler pulley mounted on the driver's side of the engine near the center of the engine block. Loosen the nut in the middle of the idler pulley with a ratchet and socket. Once the idler pulley bolt is loose, you must jack up the front end of the car to reach the top adjustable pulley adjustment bolt and to replace the bottom air conditioner V-belt.

4

Place the wheel chocks behind each rear wheel and behind each rear wheel. Raise the front of the 300M with a floor jack. Place the jack stands under the vehicle's subframe. Lower the front end onto the jack stands until they support all of the weight of the car.

5

Slide under the front of the engine again. Position the ratchet, extension and socket up through the engine compartment and onto the head of the serpentine belt idler pulley adjustment bolt. Turn the bolt counterclockwise until the belt is loose. Once the serpentine belt is loose, pull it off of the idler pulley and the other accessory pulleys. Slide the belt out through the bottom of the engine compartment.

6

Remain under the engine and locate the adjustable idler pulley to the air conditioner V-belt. The adjustable idler pulley is mounted to the lower front passenger side of the engine. Loosen the nut in the middle of the air conditioner adjustable idler pulley with the ratchet and socket. Remove the socket and reattach the extension to the ratchet.

7

Turn the adjustment bolt counterclockwise with a ratchet, socket and extension until the belt is loose. Once the belt is loose, pull it off of the idler pulley, the air conditioner compressor and the other accessory pulleys. Pull the belt out through the bottom of the engine compartment.

8

Slide the new air conditioner belt around the same pulleys including the adjustable idler pulley. Turn the adjustment bolt clockwise with the ratchet, extension and socket until the belt is tight. Once the belt is tight, check the belt tension with your hand by pushing inward on it. The belt should have no more than a half-inch of deflection at its longest span. Tighten the nut in the middle of the idler pulley with the ratchet and socket.

9

Slide the new serpentine belt around the same pulleys including the adjustable idler pulley. Turn the adjustment bolt clockwise with the ratchet, extension and socket until the belt is tight. Once the belt is tight, check the belt tension with your hand by pushing inward on the belt. The belt should have no more than a half-inch of deflection at its longest span. Move to the top side of the engine and tighten the nut in the middle of the idler pulley with the ratchet and socket..

10

Inspect both belts to ensure they are both properly seated inside of all of the accessory pulleys. Start the engine and inspect both belts to make sure both of them will remain seated with the engine running. Let the engine run for about 30 seconds. Turn the engine off and recheck the tension on both belts with your hand. Adjust the belts as needed to maintain the half-inch of deflection. Close the hood.

11

Jack the 300M up and remove the jack stands. Lower the car, pull the jack out from under and remove the wheel chocks from behind the rear wheels.