An alternator pulley, of the incorrect size, installed at the factory can be the cause of drive belt failure and illumination of the battery light. The alternator pulley should be inspected and replaced as necessary if the drive belt brakes. When the new belt installed, it must be adjusted to the proper tension.Google+
Car Problem Reports
Mercury Capri Battery Light Comes On, Belt Failure, Sometimes Repeatedly
Mercury Capri Problem
Engines Affected: 1.6L 4 Cylinder, 1.6L 4 Cylinder Turbo
Average Mileage: 126,166 mi (87,000 mi - 169,000 mi)
Visitor, 1991 Mercury Capri, 1.6L 4 Cylinder Turbo, 103,000 mi
Still in shop
Visitor, 1991 Mercury Capri, 1.6L 4 Cylinder, 87,000 mi
Alternator belt keeps snapping. Replaced alternator, and belt 3 times. Mechanics have no idea how to fix it.
Visitor, 1991 Mercury Capri, 1.6L 4 Cylinder Turbo, 121,000 mi
Alternator belt broke. Had replaced and drove it 2 days later and it broke again.
Visitor, 1993 Mercury Capri, 1.6L 4 Cylinder, 137,000 mi
had to make sure tension on belt is real tight.