Use a socket and ratchet on the 1991 Astro vans serpentine belt tensioner pulley to pull it to the side, letting tension off of the belt. remove the belt and pun the new belt on. Release the tension to hold the new belt on.
How to remove and install the serpentine belt on 1991 Chevy Blazer with AC?
how to release serpentine belt tensioner on 1991 C1500 Chevy Silverado?
a parts store
Replace serpentine belt on Chevy avalanche?HOW
I've got a better question, why is this question in the Chevy venture forum ? they have completely different engines and belts
serpentine belt for 97 7.4 454 Chevy truck
need diagram for 1994 chevy truck serpentine belt?
Put the serpentine belt on to the pulleys of your 1994 Chevy engine. Tighten a serpentine belt with the tensioner pulley.
Timing belt.
Put the new serpentine belt on to your 1992 Chevy Corsica pulleys. Push the tensioner pulley to the left to tighten the serpentine belt.
replacing serpentine belt on 2000 chevy prizm need help
How do I rethread the serpentine belt on a 2002 Malibu with a V-6?