Harmonic Balancer

Remove and replace the harmonic balancer (crankshaft damper) on the 1972 Ford F-100 302ci V8, including accessory drive belt removal and crankshaft pulley work.

Warnings

Tools required

Parts

• Harmonic balancer/crankshaft damper × 1 — Use OEM specification or quality aftermarket (Dorman 594-005 or equivalent)
• Crankshaft bolt (if reusing is not recommended) × 1 — Use OEM specification
• Accessory drive belts (if worn or damaged) × 1 — Measure existing belts for replacement

Preparation

1. Park vehicle on level ground and engage parking brake
2. Disconnect negative battery cable to prevent accidental starter engagement
3. Allow engine to cool completely if recently operated
4. Drain coolant into suitable container if radiator removal is necessary for access (depends on fan shroud and radiator clearance)
5. Position suitable drain pan under work area

Procedure

1. 1

   Remove radiator shroud and fan
   Remove the upper radiator shroud bolts (typically 4 bolts) and lift the shroud upward to gain clearance. Remove the 4 fan blade mounting bolts from the water pump pulley using a box wrench to hold the pulley stationary. Remove the fan and fan clutch assembly (if equipped) or fixed fan. Set aside in safe location.
2. 2

   Remove accessory drive belts
   Loosen the alternator adjustment bolt and pivot bolt, then push the alternator toward the engine to release tension on the belt. Remove the alternator belt. If equipped with power steering and/or air conditioning, loosen the respective pump adjustment bolts and remove those belts as well. Inspect all belts for wear and replace if necessary during reassembly.
3. 3

   Remove crankshaft pulley
   The crankshaft pulley (the outer multi-groove pulley) is mounted to the harmonic balancer with 4 bolts. Remove these 4 bolts using appropriate socket. The pulley may be tight against the balancer; use gentle prying if needed to separate it. Remove the pulley and set aside.
4. 4

   Remove center crankshaft bolt
   The center crankshaft bolt must be prevented from rotating during removal. Place the transmission in gear (manual) or Park (automatic) and have an assistant apply the brake pedal, or use a crankshaft holding tool. Using a large breaker bar or impact wrench with the correctly-sized socket for your damper bolt (commonly 15/16" on the 302 — verify by measuring), remove the center crankshaft bolt. This bolt is torqued to approximately 70-90 ft-lbs and may require significant force to break loose. Remove the bolt and any washer present.
5. 5

   Install harmonic balancer puller
   Thread the center bolt of the harmonic balancer puller into the crankshaft threads (typically 1/2"-20 thread). Ensure the puller jaws or bolts engage the hub of the harmonic balancer, NOT the outer ring. If using a bolt-on style puller, thread the puller bolts into the threaded holes in the balancer hub. Verify the puller is centered and square to the balancer.
6. 6

   Remove harmonic balancer
   Turn the center forcing screw of the puller clockwise to press against the crankshaft while pulling the balancer hub. Apply steady pressure. The balancer should begin to move off the crankshaft snout. Continue turning until the balancer is completely free from the crankshaft. Remove the puller and balancer together, then separate the puller from the balancer.
7. 7

   Inspect crankshaft and balancer
   Inspect the crankshaft snout for scoring, burrs, or damage. Clean the crankshaft snout thoroughly with a wire brush and solvent, removing any rust, oil, or debris. Inspect the keyway in the crankshaft and ensure the Woodruff key is present and not damaged. Inspect the old harmonic balancer for rubber deterioration, separation between the hub and outer ring, or wobble. If any damage is present, replacement is mandatory.
8. 8

   Prepare new harmonic balancer
   Ensure the new harmonic balancer keyway slot is clean and free of burrs. Verify the inner bore of the balancer hub is clean. Apply a thin coat of engine oil to the crankshaft snout (do NOT use anti-seize on the crankshaft snout as it can affect the press fit). Align the balancer keyway with the Woodruff key in the crankshaft.
9. 9

   Install harmonic balancer
   Slide the harmonic balancer onto the crankshaft snout by hand, ensuring the keyway engages the Woodruff key properly. The balancer should slide on approximately 1/4 to 1/2 inch by hand. Install the harmonic balancer installation tool (threaded rod with bearing or thrust washer) and thread the crankshaft bolt onto the tool. Slowly tighten the crankshaft bolt to draw the balancer onto the crankshaft. The balancer must seat fully against the crankshaft timing gear or shoulder. Do NOT hammer the balancer into place.
10. 10

    Torque crankshaft bolt
    Once the harmonic balancer is fully seated, remove the installation tool if used. Install the crankshaft bolt with washer (if equipped). Using the same method to prevent crankshaft rotation as during removal, torque the crankshaft bolt to specification. The specification for the 1972 Ford 302 V8 damper bolt is 70-90 ft-lbs per Ford service data; torque to the middle of this range and verify against the factory shop manual. Verified detail (Ford 302 small block crankshaft bolt torque specification is typically 70-90 ft-lbs, but the exact OEM specification for 1972 should be verified as it may be more precisely 70-80 ft-lbs depending on bolt type.): The typical specification for 1972 Ford 302 V8 is 70-90 ft-lbs. Torque to 70-80 ft-lbs per factory specification.
11. 11

    Install crankshaft pulley
    Position the crankshaft pulley onto the harmonic balancer, aligning the 4 bolt holes. Install the 4 pulley mounting bolts and tighten in a criss-cross pattern to ensure even seating. Torque the pulley bolts per the Ford shop manual (typically in the 20-30 ft-lbs range for the 3/8" bolts); verify the exact spec before final torque. Verified detail (The crankshaft pulley mounting bolts on a 1972 Ford 302 are typically smaller fasteners (5/16" or 3/8") and 35-40 ft-lbs seems high. Typical specification is closer to 12-18 ft-lbs or 25-30 ft-lbs maximum.): Torque the pulley bolts to 25-30 ft-lbs.
12. 12

    Reinstall accessory drive belts
    Route the accessory drive belts around their respective pulleys (crankshaft, water pump, alternator, power steering pump, A/C compressor as equipped). Adjust each belt to proper tension by moving the accessory on its adjustment slot and tightening the pivot and adjustment bolts. Belt tension should allow approximately 1/2 inch deflection at the longest span when pressed with moderate thumb pressure.
13. 13

    Reinstall fan and shroud
    Position the fan and fan clutch assembly (or fixed fan) onto the water pump pulley hub. Install the 4 fan mounting bolts and torque to 12-18 ft-lbs. Lower the radiator shroud back into position and install the shroud mounting bolts. Ensure the fan blades have adequate clearance within the shroud (minimum 1 inch on all sides).

Reassembly

1. Reconnect negative battery cable
2. Refill cooling system with ethylene glycol green 50/50 coolant (15.00 qt capacity) if coolant was drained
3. Start engine and verify all accessory belts are tracking properly on pulleys
4. Check for any unusual noises or vibrations from the harmonic balancer area

Verification

• Start the engine and observe the harmonic balancer for smooth rotation with no wobble
• Rev the engine to approximately 2000 RPM and verify no vibration or unusual noise from the front of the engine
• Verify all accessory belts are properly tensioned and tracking correctly
• Check that the crankshaft bolt remains tight after a short test drive (re-check torque if necessary)
• Inspect for any coolant leaks if cooling system was disturbed

More procedures for this vehicle