Replacement of the alternator drive belt (generator belt) on a 1966 Chevrolet Corvette 327ci V8, including tension adjustment.

Warnings

Tools required

Parts

• Alternator belt (V-belt) × 1 — Use OEM specification for 327ci V8 with standard alternator

Preparation

1. Allow engine to cool completely
2. Park vehicle on level surface and engage parking brake
3. Ensure ignition is OFF and keys are removed
4. Open hood and prop securely

Procedure

1. 1

   Locate alternator and belt routing
   Identify the alternator mounted on the side of the engine (typically driver's side on the 327). The alternator belt runs from the crankshaft pulley at the bottom, around the alternator pulley. Note the belt routing before removal for proper reinstallation.
2. 2

   Loosen alternator adjustment bolt
   Locate the alternator adjustment bolt on the slotted bracket at the top of the alternator. This is typically a 1/2" or 9/16" bolt head. Loosen this bolt approximately 3-4 turns to allow the alternator to pivot. Do not remove the bolt completely.
3. 3

   Loosen alternator pivot bolt
   Locate the lower pivot bolt that passes through the alternator mounting ear at the bottom. Loosen this bolt 1-2 turns to allow the alternator to pivot freely. This bolt does not need to be removed.
4. 4

   Push alternator toward engine
   With both bolts loosened, manually push the alternator body toward the engine block to create maximum slack in the belt. The alternator should pivot on the lower bolt, moving approximately 1-2 inches inward.
5. 5

   Remove old belt
   With slack created, lift the old belt off the alternator pulley first, then work it off the crankshaft pulley. Remove the belt from the engine compartment. Inspect the old belt for cracking, glazing, or fraying to confirm replacement was necessary.
6. 6

   Install new belt
   Route the new belt around the crankshaft pulley first, ensuring it seats properly in the pulley groove. Then stretch the belt over the alternator pulley, making sure it is centered in the pulley groove and not twisted.
7. 7

   Apply tension to belt
   Using a pry bar positioned against the alternator's cast mounting ear or front housing boss (never against the thin case body), carefully lever the alternator away from the engine to apply tension to the belt. Pull the alternator outward until proper tension is achieved. The belt should deflect approximately 1/2 inch when pressed firmly midway between pulleys.
8. 8

   Tighten adjustment bolt
   While maintaining tension on the alternator with the pry bar, tighten the upper adjustment bolt fully to lock the alternator in position. Ensure the alternator does not slip inward as you tighten.
9. 9

   Tighten pivot bolt
   Tighten the lower pivot bolt firmly to secure the alternator mounting. This bolt should be snug but not over-torqued as it passes through the alternator mounting bracket.
10. 10

    Check belt tension and alignment
    Press firmly on the belt midway between the crankshaft and alternator pulleys. The belt should deflect approximately 1/2 inch with firm thumb pressure. Visually confirm the belt is properly seated in all pulley grooves and aligned without rubbing on any brackets or components.

Reassembly

1. No disassembly was required beyond belt removal

Verification

• Start the engine and observe belt operation for 30 seconds, listening for squealing or chirping that indicates improper tension or alignment
• Check that the alternator pulley rotates smoothly without wobble or noise
• Verify the charging system warning light (if equipped) extinguishes after engine start, indicating the alternator is functioning
• Recheck belt tension after 50-100 miles of driving, as new belts may seat and require retensioning

More procedures for this vehicle