Serpentine Belt chevy g20

first is alternator/ water pump/ crank... second is power steering and smog if equipted.. last is ac compressor..

replace ac compressor,,they will lock up in some cases,,causes the engine to not even turn over,,plz replace ac compressor ,,try to take belt off see if it turns free by hand!

Okay, there are a few engines that come in this van, lucky there the same except,they come with or without ac or airpump, so i will give you all of them and you choose the right one.

DRIVE BELT DECAL SHOULD BE UNDER THE HOOD.OR YOU CAN GO TO DEALERSHIP GET ONE AUTO ZONE OR ADVANCE AUTO PARTS CAN GET YOU ONE.OR YOU CAN BUY A HAYNES REPAIR MANUAL IT HAS BELT DIAGRAM.

My sincere apologies for the delayed response.
I am personally going back to answer your unanswered questions.

I do not know if you still need this information, but I am going ahead and answering it anyway. You may want to Print the Diagrams for future use.

I am assuming this "van" is a Chevy Venture?
CLICK on the following LINK. It has the Belt Diagrams you will need.
If you would: Before Clicking: Let me know if this helped you, or if you have any additional information or questions. Feel Free to contact me at FixYa.com!
Again my apologies...
http://www.2carpros.com/car_repair_information/year/2000/make/chevrolet/model/venture/2000_chevrolet_venture_drive_belt_routing_diagram.htm

remove serpentine belt,basically remove every thing in the way, WHAT ENGINE?

you will need some fairly long wrenchs 15mm-16mm to get leverage on the spring loaded serp tesiner put a wrench on the pulley near the belt ? also loosen the 4 fan bolts on the water pump before you remove the belt ? ther are 7 fan shroud bolts you can split the fan shroud ? 2 bolts on the lower right and 2 on the left ? after you do this then you should be down to pulling off the fan and pulley just slides off ? then remove the 4 waterpump mounting boltss, scrape the old gaskets ? when this is done all you have left is to installthe fan studs from the old pump? you do this by screwing down 2 nuts on the stud then with 2 wrenchs lock the nuts together ? then unscrew the bottom nut ? keep doing that till all 4 are replaced? install the gaskets and add some silicone and reverse the process ? hope this helps repost thumbs up !!

there should be a diagram under the hood showing you how the belt goes on but try this website its www.autozone.com to see if they have your van listed i also would like to give you a place that sells only GM-parts only its Schram auto & truck part the number is 1800-292-1032 if you ever have a part that is hard to find.

there should be a diagram sticker under the hood . first thing check to make shure all accesories move freely no locked pullys that may have shot the belt to begin with

The serpentine belt is the most common cause for whining sound when accelerating, try to understand if noise is coming from serpentine belt.

Also check power steering belt under steering column, and also the rotor and chain, thei do not make whining noise , but can make noise when accelerating.

The belt is first suspect.