fuel

Fuel Cap

for 1966 Chevrolet Corvette 327ci V8 · RWD

Difficulty

Easy

Time

6 min

Tools

Steps

✓Expert-verified. This procedure has been reviewed by a person. Always follow the vehicle's factory service information and torque specs.

Replacement of the fuel filler cap on a 1966 Chevrolet Corvette, including inspection of the cap seal and filler neck for damage or corrosion.

Warnings

⚠Fuel vapors are flammable. Perform this work in a well-ventilated area away from ignition sources, sparks, and open flames.

ℹ️The 1966 Corvette uses a vented fuel cap. Using a non-vented cap can cause fuel tank vacuum and fuel delivery issues.

Fuel filler cap × 1 — Use OEM specification or equivalent with correct venting for 1966 model

Ensure vehicle is parked on level ground with engine off and cool
Locate the fuel filler door on the driver side rear quarter panel behind the door

1
Open fuel filler door
Open the hinged fuel filler door located on the driver side rear quarter panel. The door is accessed by pressing the release and swinging it open on its hinge.
2
Remove existing fuel cap
Remove the fuel cap from the filler neck. Note the cap type fitted: original 1966 caps may be a screw-on threaded cap or a cam/bayonet-style cap — remove accordingly (counterclockwise for threaded type). Verify cap style before installing a replacement.
3
Inspect filler neck
Examine the exposed fuel filler neck threads and sealing surface for damage, corrosion, or debris. Clean any dirt or corrosion from the threads using a clean rag. Check that the neck is not bent or deformed.
4
Inspect old cap seal
Check the rubber seal on the old cap for cracks, hardening, or deterioration. Verify the cap venting mechanism is present and not clogged. A damaged seal or blocked vent indicates replacement is necessary.
5
Install new fuel cap
Install the new fuel cap onto the filler neck per its design (rotate clockwise for a threaded type, or engage the cam/bayonet lock as applicable). Seat the cap firmly against the neck seal. Do not overtighten; hand-tight is sufficient.
6
Close fuel filler door
Close the fuel filler door and ensure it latches securely flush with the body panel.

Verify the fuel cap is snug and does not continue to rotate freely
Check that the cap seals properly with no fuel odor escaping from the filler neck
Confirm the fuel filler door closes and latches correctly
Start the engine and allow it to idle for 1 minute, then check for fuel vapor odor around the filler area