Fuel Injectors - All

Removal and replacement of all eight fuel injectors on a 1966 Chevrolet Corvette 327ci V8 equipped with Rochester fuel injection system.

Warnings

Tools required

Parts

• Fuel injector (Rochester type) × 8 — Use OEM specification
• Injector O-ring seal kit × 1 — Use OEM specification
• Fuel rail gasket set × 1 — Use OEM specification
• Throttle body gasket × 1 — Use OEM specification
• Fuel filter × 1 — Use OEM specification
• Vacuum line assortment (if damaged) × 1 — Use OEM specification

Preparation

1. Ensure the engine is completely cold before beginning work
2. Disconnect the negative battery cable to prevent electrical shorts and fuel pump activation
3. Place a large drip pan under the vehicle to catch any fuel spillage
4. Have multiple shop towels ready to absorb fuel spills immediately
5. Photograph or sketch all vacuum line routing and linkage positions from multiple angles for reassembly reference
6. Label each vacuum line with tape and marker before disconnection
7. Remove the engine air cleaner assembly and set aside in a clean area
8. Clean the exterior of the fuel injection unit with a degreaser to prevent dirt entry during disassembly

Procedure

1. 1

   Relieve fuel system pressure
   Remove the fuel pump fuse or disconnect the fuel pump relay if equipped. Attempt to start the engine and allow it to run until it stalls from fuel starvation. Crank the engine for 5 seconds after stalling to ensure complete depressurization. On this mechanical system, also open the fuel line at the filter slowly using two wrenches to relieve any remaining pressure. Catch fuel in a drip pan.
2. 2

   Disconnect fuel supply and return lines
   Locate the fuel inlet line at the fuel meter body on the front of the injection unit. Use two wrenches (one to hold, one to loosen) to disconnect the fuel inlet line. Disconnect the fuel return line at the pressure regulator. Cap or plug all open fuel lines immediately to prevent contamination and fuel leakage. Expect residual fuel to drain from lines.
3. 3

   Disconnect electrical connections
   Disconnect the electrical connector from each of the eight fuel injectors by squeezing the locking tab and pulling straight up. Label each connector with tape indicating its cylinder position (driver front, driver rear, etc.) to ensure correct reconnection. On this mechanical system, also disconnect any electrical connections to the cold start valve if equipped.
4. 4

   Remove throttle linkage and control cables
   Disconnect the throttle linkage rod at the throttle lever by removing the cotter pin and clevis pin. Remove the throttle return spring. If equipped with automatic transmission, disconnect the kickdown cable at the throttle lever. Remove the choke cable if equipped. Mark the exact position of all linkage adjustment points before disconnection.
5. 5

   Disconnect vacuum lines
   Carefully disconnect all vacuum lines from the fuel meter body, throttle body, and manifold vacuum fittings. The Rochester system uses approximately 10 vacuum connections including distributor advance, power brake booster, PCV system, and fuel pressure regulator. Follow your labeled diagram created during preparation. Use needle nose pliers to loosen stuck hoses without tearing.
6. 6

   Remove fuel meter body mounting bolts
   Remove the 4 bolts securing the fuel meter body (distribution block) to the intake manifold plenum. These are located at the corners of the rectangular meter body casting. Support the meter body as you remove the final bolt to prevent it from falling and damaging injectors or linkage.
7. 7

   Remove fuel meter body and injector assembly
   Carefully lift the fuel meter body assembly straight up and away from the intake manifold. The eight injectors will remain inserted in the manifold ports initially. Work slowly to avoid bending fuel lines or damaging injector tips. Place the assembly on a clean workbench protected with shop towels.
8. 8

   Extract injectors from intake manifold
   Each injector is held in its intake manifold port by an O-ring seal and may be stuck due to fuel varnish. Grasp each injector firmly and pull straight up with a twisting motion. If injectors are severely stuck, use an injector puller tool hooked under the electrical connector flange. Do not pry against the injector body or tip as damage will result. Remove all eight injectors and immediately cover the open intake ports with clean shop towels to prevent debris entry.
9. 9

   Remove injectors from fuel meter body
   Each injector connects to the fuel meter body via a fuel line and mounting bracket. Remove the small retaining clip or bracket bolt securing each injector to the meter body. Disconnect the fuel supply tube from each injector using two wrenches to prevent twisting the injector body. Keep injectors organized by cylinder position.
10. 10

    Inspect and clean intake ports
    Inspect each intake manifold injector port for carbon buildup, damage, or corrosion. Use a wire brush to clean the port opening without allowing debris to fall into the manifold. Wipe clean with shop towels. Inspect the O-ring sealing surface for scratches or damage that could cause vacuum leaks.
11. 11

    Prepare new injectors for installation
    Remove new injectors from packaging. Lubricate all new O-rings with clean engine oil or petroleum jelly. Install new O-rings on each injector at both the tip seal and upper body seal positions. Inspect each new injector tip for damage and ensure the pintle moves freely.
12. 12

    Install injectors into intake manifold
    Install each new injector into its corresponding intake manifold port by pushing straight down with a gentle twisting motion until the injector seats fully against the manifold. The O-ring should compress and the injector should sit flush or slightly below the manifold deck surface. Install all eight injectors before proceeding.
13. 13

    Connect injectors to fuel meter body
    Position the fuel meter body above the installed injectors. Connect each injector fuel supply tube to its corresponding fitting on the fuel meter body using two wrenches. Install the retaining clips or bracket bolts to secure each injector to the meter body structure. Ensure all connections are tight but do not overtighten and damage the brass fittings.
14. 14

    Install fuel meter body assembly
    Install a new gasket on the intake manifold plenum surface where the fuel meter body mounts. Carefully lower the fuel meter body assembly with all injectors attached onto the intake manifold, guiding each injector into its port simultaneously. This requires patience and may need a helper. Install the 4 mounting bolts finger-tight, then tighten in a cross pattern to ensure even seating.
15. 15

    Reconnect vacuum lines and linkage
    Reconnect all vacuum lines according to your labeled diagram and photographs. Ensure each connection is fully seated and secure. Reconnect the throttle linkage, return spring, kickdown cable, and choke cable. Adjust throttle linkage to achieve full throttle opening and proper idle position. Install new cotter pins on clevis pin connections.
16. 16

    Reconnect electrical and fuel connections
    Reconnect the electrical connector to each fuel injector according to your cylinder position labels. Each connector should click into place when fully seated. Reconnect the fuel supply and return lines using two wrenches. Ensure connections are tight without overtightening.
17. 17

    Prime fuel system and check for leaks
    Reconnect the negative battery cable. Turn the ignition key to the ON position without starting the engine. On this mechanical system, the fuel pump will run continuously, so monitor carefully. Inspect all fuel connections for leaks. Turn the key OFF if any leaks are detected. Tighten connections as needed. Once leak-free, turn the key ON again and observe fuel pressure stabilize.

Reassembly

1. Reinstall the engine air cleaner assembly with a new filter element
2. Double-check all vacuum line connections against your reference photographs
3. Verify throttle linkage achieves full range of motion without binding
4. Ensure all electrical connectors are fully seated and locked
5. Verify no tools or shop towels were left in the engine compartment

Verification

• Start the engine and listen for smooth idle operation without misfires or rough running
• Observe fuel pressure gauge reading (should stabilize at 18-20 psi on this system)
• Inspect all fuel connections for leaks while the engine is running
• Test throttle response by slowly increasing engine speed and ensuring smooth acceleration without hesitation
• Allow engine to reach operating temperature and verify no vacuum leaks (rough idle or hissing sounds)
• Road test the vehicle to verify proper power delivery, smooth acceleration, and no fuel odor in the cabin
• Recheck all fuel connections for leaks after the test drive when the system is at full operating pressure

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