Problem with replacing serpentine belt on ml430

There will be a spring loaded tensioner pulley keeping the belt tight. On the pulley arm, there should be a square hole that fits a 3/8" ratchet or pull bar. Put the pull bar in the hole and pull the pulley away from the belt to remove. Repeat to reinstall the belt. You might have to remove something to make this accessible.

if you mean serpentine belt, there is a tensioner pulley that keeps it tight. remember how it goes between everything for when you put the new one on. use the tensioner pulley to relieve the tension (it will move inward towards the engine) and while holding the pulley, slip the old belt off. then fit the new one around everything else before the tensioner pulley. then pull the tensioner pulley inwards again, slip the new belt over the tensioner pulley, then let it out slowly. make sure that all of the cogs on the belt are in the right place of the pulleys (if they arent, it will most likey slip into place when the engines starts but still might not want to chance it)

1. 1 Check to ensure the Sienna's engine is cold, then make sure the Sienna is in park, the ignition is in the off position and the key is removed from the ignition to prevent any possibility of the engine engaging during the serpentine belt replacement.
   
2. 2 Open the hood and locate the serpentine belt routing diagram sticker on the side of the engine casing. Study it for a moment before removing the existing belt. It is essential the new belt be installed exactly as the diagram indicates.
   
3. 3 Find the tensioner pulley, the main pulley that controls the serpentine belt, and fit a 1/2-inch socket wrench over the self-tensioner on the outside of the pulley.
   
4. 4 Pull the wrench to the left to move the pulley forward, which loosens the belt, then remove the belt.
   
5. 5 Compare the old serpentine belt with the new, replacement belt for length, width and number of grooves on the belt's underside. Be certain the replacement belt is the right part.
   
6. 6 Fit the new belt on to each pulley according to the serpentine belt routing diagram on the manufacturer's sticker, or according to the drawing made prior to removing the old belt. Fit the new belt on to the tensioner pulley last, again applying pressure on the pulley's self-tensioner with the half-inch socket wrench to loosen the pulley.
   
7. 7 Release the pressure on the self tensioner and allow the tensioner pulley to ease back into place, thereby tightening the new serpentine belt with the appropriate tension.
   
8. 8 Remove the wrench and close the hood.
   

Thank you and good luck,
Lee

The tensioner will keep the belt tight without having to adjust. It's on a spring loaded type arm. The tensioner is on a arm, if you look at the center of the roller you will see either a 1/2" hole or it could be a allen type wrench hole. You will need to fit a ratchet into the hole or an allen wrench with a pull handle for better leverage. Once you have this inserted into the hole, you will either push or pull slightly to compress the spring which will give you room to fit the belt over the last pulley. Once this is done the tensioner will automatically tighten the belt once you release the pull handle. You are set and ready to go

Which engine?
To replace the drive belt or serpentine belt on a Voyager check the engine size. For 2.4L engines, a serpentine belt runs the air conditioning compressor and alternator. For 3.0L models, the alternator and power steering share a belt with a separate belt for the AC. Dodge recommends checking the belts every 15,000 miles or 12 months for possible replacement. I have gone 3 yrs with one.. it will start squealing when you turn on the heater to defrost..

http://www.automd.com/46/how-to-replace-a-serpentine-belt/

Most replacement belts have a diagram on the package. However, the easiest way is to pay close attention to the belt you are taking off, and replace the new one the same way. The pulleys themselves are usually 'grooved' or 'smooth' which tells you whether the front or back of the belt is against it. The hardest part is figuring out how to release tension on the idler-pulley. If you can get the belt on and the idler/tension pulley (same thing) pulls the belt tight, chances are you got the belt right. If you don't know what I mean, then the mostest best way is to get a Clymer Manual and read up. Its really a simple thing to do yourself.

I used a long heavy duty screw driver to release the tension on a Pontiac Sunbird.. the belt will only fit on one way..

It is sometimes pretty tough getting it to move.
Make sure you are Rotating it the correct way.
Do you have a Breaker Bar or a Serpentine Belt Tensioner Tool. Stores like Harbor Freight and even some Auto Parts Stores have these. Some of the auto parts stores have these for rent (for free with a refundable deposit).
I like and use weekly the Serpentine Tool from Harbor Freight (Item #66344-0VGA- $20). It is narrow enough to fit in most tight spots. The main bar has a 3/8-in fitting, and the extension bar can connect to this with a 1/2-in fitting.
The idea is to have more leverage. The Ratchet and/or Wrench sometimes does not provide that leverage needed.

When installing follow the below guidelines. DO NOT try to put the Belt on the Tensioner last.

"HOW TO":
Standard Rules to Removal the Serpentine Belt with an Automatic Tensioner:
1. Find the Tensioner(s).
2. Using a Serpentine Belt Tensioner Tool, Or Wrench OR Ratchet, Rotate/Move the Tensioner USING THE AVAILABLE NUT (on the Pulley or Arm Base) OR the OPENING (3/8ths or 1/2 inch square opening) rotating the Tensioner Pulley/Arm - moving it away from contact with the belt and towards the area where the belt is not in contact with the Tensioner Pulley. The Tensioner is spring loaded, and is hard to rotate/move.
3. Remove the loosened belt off one of the other more easily accessed Pulleys.
4. DO NOT quickly release the Tensioner, but gently allow the Tensioner to rest in its closed position.

Standard Rules for Installing the Serpentine Belt with an Automatic Tensioner:
a. Pick a Pulley that is most easily accessed. This will usually be on top. This will be the last Pulley that the belt will go on.
b. Using the Diagram: Install the new Serpentine Belt on the remainder of the Pulleys....over, under, left right.
c. Using a Serpentine Belt Tensioner Tool or Wrench or Ratchet Tool: Rotate/Move the Tensioner Pulley/Arm "away" from Belt contact area on the Tensioner. This spring is pretty hard and with a new belt, it will be even harder to install. Rotate/Move this to as-close to the maximum allowed inorder to have enough slack in the belt to get it up and over the last pulley.
d. Using your other hand - Pull the Belt up and over the Last remaining Pulley.
e. Before releasing the pressure on the Tensioner, visually inspect the remainder Pulleys and the Belts' Positioning on them.
Let me know if this helped, or if you have additional information questions. Feel Free to contact me at FixYa.com!

When this idler wears out it makes a growling noise that changes with engine RPM. A Bad Idler Pulley May Wobble & Wear Out Your Serpentine Belt Prematurely. Get Rid Of That Horrible Noise & Change.

Remove the serpentine belt by using a breakover bar, ratcher or serpentine belt removal tool with the correct size socket for the pulley mounting bolt. Rotate tensioner arm to release tension. Remove the bel. Using the proper size socket, remove the tensiones mounting bolt and remove tensioner.

Before installing the new tensioner, make sure the mounting surface for the tensiones is clean and free rust or other obstructions. Find the locator pin hole and rotate the replacement tensiones until the locator pin and the hole line uo. Insert the pin into the hole. Reinstall the mounting bilt and torque down to tight fit.

Rotate the tensioner arm to install the serpentine belt. Make sure the belt is correctly fitted to all pulley in the drive system. Start the engine to check for any problems. Extreme care should be taken when reinstalling the serpentine belt because some of the pulleys are located in remote positions ans it is very hard to see that belt is seated properly in all of the grooves. If the belt isn't seated properly, the belt can "ride out" of the grooves and the belt can be damaged.

Also must review the ZJ Repair Manual Secc-7-Cooling-System for graphics references.

Hope helped with this. Remember rated this help. Good luck.

There should be a belt routing diagram located on a sticker on the radiator support under the hood.
to fit the belt, there is a spring loaded belt tensioner that is moveable and holds tension on the belt. Turn the belt tensioning pulley in one direction to allow you to fit the belt over it after the belt is in all the other pulleys.
Then release the tensioner onto the belt.
k

joecoolvette must not ever been near an A4 Audi. Although his outline of the serpentine belt change is correct, you can't get to on an A4. Check out AudiWorld Tech Articles, Chris Hansen has a nice post there on Serpentine Belt Tensioner Replacement that would address most of this question.

on the tensioner you may have a square hole were you can fit a 3/8 drive ratchet if not then you may have a bolt usually 15mm where you can put a socket and swing the tensioner inorder to release tension most likely the square hole.