Full Engine Tune-Up

Complete tune-up service including spark plugs, ignition points, distributor cap and rotor, condenser, PCV valve, fuel filter, air filter, and ignition timing adjustment for the 302 V8.

Warnings

Tools required

Parts

• Spark plugs (8 total) × 8 — Autolite 25 or equivalent (0.044" gap)
• Ignition point set × 1 — Use OEM specification
• Condenser × 1 — Use OEM specification
• Distributor cap × 1 — Use OEM specification
• Distributor rotor × 1 — Use OEM specification
• Air filter × 1 — Use OEM specification
• Fuel filter (inline) × 1 — Use OEM specification
• PCV valve × 1 — Use OEM specification
• Spark plug wire set × 1 — Use OEM specification (if worn)

Preparation

1. Park vehicle on level surface and engage parking brake.
2. Allow engine to cool completely for at least 2 hours if recently operated.
3. Disconnect negative battery cable.
4. Gather all tools, parts, and supplies before beginning.
5. Clean engine bay around distributor and spark plug areas with compressed air or brush to prevent debris from entering cylinders.

Procedure

1. 1

   Remove and inspect spark plug wires
   Label each spark plug wire with cylinder number using masking tape. Remove wires by grasping boot at spark plug (not wire) and twisting while pulling. Inspect wires for cracks, burns, or excessive resistance. Check wire routing to ensure they will not contact exhaust manifolds.
2. 2

   Remove old spark plugs
   Using 5/8" spark plug socket, remove all 8 spark plugs. Note: The 302 V8 has cast iron heads. Inspect each plug for fouling, electrode wear, and correct heat range. Inspect plug threads in cylinder head for damage.
3. 3

   Install new spark plugs
   Apply a light coat of anti-seize compound to threads of new spark plugs (avoid getting compound on electrodes). Verify plug gap is set to 0.044" using feeler gauge. Hand-thread each plug to avoid cross-threading. Torque each plug individually to specification (reduce dry torque spec by approximately 10-20% when anti-seize is used).
4. 4

   Remove distributor cap and rotor
   Remove 2 spring clips or screws securing distributor cap. Lift cap with wires attached and secure out of the way. Remove rotor by pulling straight up (it is held by friction fit on shaft). Inspect cap terminals and rotor tip for carbon tracking, corrosion, or excessive wear.
5. 5

   Replace ignition points and condenser
   Disconnect primary wire and condenser wire from point terminal. Remove condenser mounting screw and remove condenser. Remove 2 point set mounting screws. Install new condenser and secure with mounting screw. Install new point set with 2 mounting screws, leaving them slightly loose for adjustment.
6. 6

   Set point gap (dwell)
   Rotate engine by hand using wrench on crankshaft bolt until rubbing block of points is on high point of distributor cam lobe. Using feeler gauge, adjust point gap to 0.025" (initial setting). Tighten point set mounting screws securely. Reconnect primary wire and condenser wire to point terminal. Final dwell adjustment will be performed with engine running.
7. 7

   Install new rotor and distributor cap
   Install new rotor onto distributor shaft, aligning square and round locating holes. Press down firmly until seated. Install new distributor cap, ensuring it seats properly on distributor body. Secure with 2 spring clips or screws. Reconnect spark plug wires in correct firing order: 1-5-4-2-6-3-7-8, with distributor rotation counterclockwise, #1 cylinder at front driver side. Verified detail (The Ford 302 firing order is 1-5-4-2-6-3-7-8, which is correct. However, the Ford 302 distributor rotation is COUNTERCLOCKWISE which is correct for small-block Ford. This detail should be verified but appears correct; the firing order and rotation are consistent with the 302 (non-HO). Flagging per instructions to verify explicit firing order/rotation claims.): Reconnect spark plug wires in correct firing order: 1-5-4-2-6-3-7-8, with distributor rotation counterclockwise, #1 cylinder at front of passenger-side (right) cylinder bank.
8. 8

   Replace PCV valve
   Locate PCV valve in passenger side valve cover (typically in rubber grommet). Pull PCV valve from grommet. Disconnect hose from PCV valve. Install new PCV valve into hose, then press assembly back into valve cover grommet until seated.
9. 9

   Replace air filter
   Remove air cleaner wing nut and lift off air cleaner lid. Remove old air filter element. Wipe out air cleaner housing with clean rag. Install new air filter element. Reinstall air cleaner lid and secure with wing nut.
10. 10

    Replace fuel filter
    Locate fuel filter (typically a cartridge-style filter in the carburetor inlet fitting or an inline filter in the fuel line). If cartridge-style, use appropriate wrench to remove inlet fitting and replace filter element. If inline style, use two wrenches to loosen hose clamps on both sides of filter. Remove old filter, noting direction of flow arrow. Install new filter with flow arrow pointing toward carburetor. Tighten hose clamps securely.
11. 11

    Reconnect battery and perform initial start
    Reconnect negative battery cable. Ensure transmission is in Park (automatic) or Neutral (manual). Start engine and allow to reach normal operating temperature. Check for fuel leaks at filter and ensure all plug wires are properly seated.
12. 12

    Set dwell angle
    With engine at normal operating temperature and idling, connect dwell meter to coil negative terminal. Dwell should read 26-31 degrees for 8-cylinder. If adjustment needed: stop engine, remove distributor cap, slightly loosen point mounting screws, adjust point gap (increase gap to decrease dwell, decrease gap to increase dwell), tighten screws, reinstall cap, restart and recheck.
13. 13

    Set ignition timing
    Locate timing marks on harmonic balancer and timing tab (front of engine, driver side). Connect timing light to #1 spark plug wire. Disconnect and plug vacuum advance hose at distributor. With engine idling at specified RPM (typically 600 RPM in Park (automatic) or Neutral (manual)), aim timing light at timing marks. Initial timing should be per specification on underhood emissions label (typically 6 degrees BTDC, but verify for your specific vehicle). To adjust: loosen distributor hold-down bolt, rotate distributor body (rotate opposite the rotor's direction of travel to advance, same direction as rotor travel to retard), tighten hold-down bolt when correct timing achieved. Verified detail (Initial timing spec for a 1972 302 varies by transmission and emissions calibration; commonly around 6 degrees BTDC but should be verified against the vehicle's emission decal / Ford service specs, which may differ (some 1972 302 applications call for different values).): Initial timing should be set per the underhood emission decal (typically approximately 6 degrees BTDC for the 1972 302 — verify against Ford specifications for this specific application).
14. 14

    Final adjustments and idle speed
    Reconnect vacuum advance hose to distributor. Verify idle speed is set correctly per underhood emissions label (typically 600-700 RPM in Park or Neutral). Adjust idle speed screw on carburetor if necessary. Check idle mixture screws are properly set (typically 1.5 turns out from lightly seated as baseline).

Reassembly

1. Ensure all vacuum hoses are reconnected properly.
2. Verify spark plug wires are routed away from exhaust manifolds and not crossing each other.
3. Double-check that distributor cap is fully seated and secured.
4. Confirm air cleaner assembly is properly installed and wing nut is tight.

Verification

• Engine should start readily and idle smoothly without missing or hesitation.
• No fuel leaks present at fuel filter connections.
• Timing light confirms timing is set to specification at idle.
• Dwell meter confirms dwell angle is within 26-31 degree range.
• Engine accelerates smoothly without stumbling when throttle is blipped.
• No abnormal noises from ignition system (arcing, clicking).
• All spark plug wires are firmly seated on plugs and distributor cap.
• Exhaust smoke is minimal and consistent (no white or blue smoke indicating plug issues).

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