Replace or remove the oil level sensor (if equipped) on a 1966 Chevrolet Corvette 327ci V8, typically located on the engine oil pan.

Warnings

Tools required

Parts

• Oil level sensor (if replacing) × 1 — Use OEM specification or aftermarket equivalent
• Copper crush washer (if applicable to sensor type) × 1 — Use OEM specification

Fluids

• 5W-30 Conventional engine oil — 1 qt

Preparation

1. Park vehicle on level ground and engage parking brake
2. Place wheel chocks behind rear wheels
3. Allow engine and oil to cool completely (minimum 2 hours after operation)
4. Raise front of vehicle using floor jack at appropriate jacking point on front crossmember
5. Secure vehicle on jack stands placed under frame rails
6. Verify vehicle stability before working underneath

Procedure

1. 1

   Locate the oil level sensor
   Position yourself under the vehicle with adequate lighting. The oil level sensor, if equipped, is typically threaded into the passenger side of the oil pan near the rear, or may be on the driver side depending on pan configuration. It will have a single wire connector. Note that many 1966 Corvettes only have an oil pressure sending unit on the engine block, not a level sensor in the pan.
2. 2

   Disconnect the electrical connector
   Locate the wire connector on the oil level sensor. Press the release tab or pull the connector straight off the sensor terminal. If corrosion is present, apply penetrating oil and allow to soak for 5 minutes before attempting removal. Some sensors may have a threaded connector that unscrews.
3. 3

   Position drain pan
   Place an oil drain pan directly beneath the oil level sensor. Expect approximately 0.5 to 1 quart of oil to drain when the sensor is removed, depending on oil level in the pan.
4. 4

   Remove the oil level sensor
   Using the 1-1/16" deep socket or oil pressure sending unit socket, carefully unthread the sensor from the oil pan. Turn counterclockwise slowly. Once the threads are disengaged, quickly remove the sensor and allow oil to drain into the pan. Keep shop rags ready to catch any spillage.
5. 5

   Inspect the oil pan threads
   Once oil drainage slows, use a flashlight to inspect the threaded hole in the oil pan. Check for damaged threads, metal shavings, or debris. Use a wire brush to clean the threads if necessary. If threads are severely damaged, the oil pan may require extraction and thread repair or replacement.
6. 6

   Prepare the new sensor
   If installing a new sensor, apply a thin coat of thread sealant to the threads, starting 2 threads back from the tip. Do not apply sealant to the first 2 threads to prevent contamination entering the oil pan. If the sensor uses a copper crush washer, install it on the sensor body.
7. 7

   Install the oil level sensor
   Thread the new (or cleaned original) sensor into the oil pan by hand, turning clockwise. Ensure the sensor threads in smoothly without resistance. Once hand-tight, use the 1-1/16" socket to snug the sensor. Tighten firmly but do not over-torque, as the oil pan is thin stamped steel and can crack. Tighten to approximately hand-tight plus 1/4 turn.
8. 8

   Reconnect electrical connector
   Push the electrical connector onto the sensor terminal until it clicks into place. Ensure the connection is secure and the locking tab engages. If the connector is threaded, hand-tighten and then snug with fingers only.
9. 9

   Lower vehicle and check oil level
   Carefully remove jack stands and lower the vehicle to the ground. Open the hood and remove the engine oil dipstick. Check the oil level and add 5W-30 conventional oil as needed to bring level to the full mark on the dipstick. Account for the oil lost during sensor removal (approximately 0.5 to 1 quart).
10. 10

    Check for leaks
    Start the engine and allow it to idle for 2 minutes. Shut off the engine and immediately inspect the oil level sensor installation point from underneath the vehicle using a flashlight. Look for any signs of oil seepage around the sensor threads. If leakage is observed, the sensor may need to be removed, cleaned, re-sealed, and reinstalled.

Reassembly

1. Ensure electrical connector is fully seated and locked onto sensor terminal
2. Verify no tools or rags were left under the vehicle
3. Dispose of drained oil properly at a recycling center

Verification

• Start engine and verify oil pressure gauge reads normal operating pressure (40-60 PSI at idle when warm)
• Check for oil leaks around sensor after engine reaches operating temperature
• If vehicle has oil level warning light, verify it illuminates during key-on/engine-off and extinguishes after engine start with proper oil level
• Re-check oil level on dipstick after test drive and top off if necessary

More procedures for this vehicle