AutoZone Product & HowTo Info | |

Search suggestions

    My Vehicles

    Add a Vehicle

    Find a Store

    Select Store

    Save 20% Sitewide

    Use Code: YOUCHOOSE20

    See Details

    Get A $25 Gift Card

    Use Code: YOUCHOOSE25

    See Details

    Harmonic Balancer

    Inspect/Replace

    • The harmonic balancer (vibration damper) is inspected for signs of wear in its center bore.
    • Also inspect the rubber mounting for indications of twisting and deterioration.
    • The outer ring can slip, causing an out of balance condition. Replace any harmonic balancer that has slipped.
    • With the cylinder head removed and the piston at top dead center (TDC), make a visual comparison. Do the timing marks for TDC on the timing cover and damper appear to be accurate.
    • Be sure the damper is the correct one for the vehicle. The wrong one can be worse than none at all.
    • Sometimes a damper can become loose on the crank. Check the keyway for wear that can result from improper damper installation, the wrong size key, or a loose damper hub to crank fit.
    • Be sure all pulleys are straight. A damaged pulley can force a crankshaft to bend during engine operation.

    Noises

    A heavy rumble or thumping noise that is most clearly heard when the vehicle is accelerated from an idle indicates a loose or worn harmonic balancer. Harmonic balancer noises are located at the front of the engine. If the harmonic balancer is worn or damaged, engine vibration may accompany the noise.

    AutoZone Logo