How do you replace the serpentine belt on a '93 Plymouth Grand Voyager 3.3l 6-cylinder?
I will presume that your vehicle has air conditioning. There is a spring loaded belt tensioner that needs to be 'relaxed'. You will need a 15mm socket with a ratchet, and a short length (12-18")of pipe that can fit over the ratchet handle (allows for more leverage). The tensioner is located ( as you stand facing the engine from the passenger side fender), to the left of the water pump and above and to the right of the crankshaft. Position the belt around all the other pulleys and idlers first (sites such as Dayco have belt routing diagrams). Place your ratchet on the 15mm nut in the centre of the tensioner pulley, and pull your lever(pipe) towards the front of the van (clockwise). This will rotate the tensioner downwards, allowing you to slide the belt onto the pulley. Note- when placing your ratchet onto the nut, you must put it 'through' the belt first, otherwise when you rotate the tensioner you will not be able to slide the belt into position because your ratchet will interfere.
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When I changed mine, it made it much easier to leave the belt off of the alternator, but on the pulley itself. This way you don't have to worry about looping the wrench you are trying to use, and once you release tension enough you can put the belt over the alternator.
This is honestly a very easy belt to replace. I myself have had to put my belt back of multiple times over the last 6 months because for some reason it keeps falling off. But I've done it so many times now that i don't even need to look at the belt diagram anymore and you only need 3 tools. A breaker bar a size 14mm ratchet head and i use a flat head screw driver to take off the radiator hose that runs from the radiator to the engine that way you have plenty of room for your hands while putting the belt on.