Coolant Reservoir

Replace or install the coolant recovery reservoir on a 1966 Chevrolet Corvette 327 V8, including mounting bracket and hose connections.

Warnings

Tools required

Parts

• Coolant recovery reservoir × 1 — Use OEM specification or aftermarket equivalent
• Reservoir mounting bracket × 1 — Use OEM specification if damaged
• Overflow hose (3/8" ID) × 1 — Replace if cracked or hardened
• Hose clamps × 2 — 5/8" worm-gear style

Fluids

• DEX-COOL Extended Life (Orange) — 1 qt

Preparation

1. Ensure engine is completely cold to the touch (minimum 2 hours after last operation)
2. Park vehicle on level ground and engage parking brake
3. Place drain pan under radiator area to catch any coolant spillage
4. Open hood and secure with prop rod
5. Inspect existing reservoir location (typically driver side inner fender or radiator support) to confirm mounting method

Procedure

1. 1

   Relieve cooling system pressure
   Carefully remove the radiator cap by pressing down and turning counterclockwise to the first stop, allowing any residual pressure to escape. Wait for any hissing to stop, then press down again and remove completely. Set cap aside on a clean surface.
2. 2

   Remove overflow hose from old reservoir
   Locate the overflow hose connected to the reservoir cap or inlet. Use needle-nose pliers to squeeze and slide the hose clamp away from the connection point. Gently twist and pull the hose from the reservoir nipple. Some coolant will drain from the hose; direct it into the drain pan.
3. 3

   Disconnect radiator overflow tube
   Trace the overflow hose to where it connects to the radiator neck overflow tube (small tube extending from radiator filler neck). Loosen the hose clamp and disconnect the hose. If the hose is hardened or cracked, discard it and prepare to install new hose during reassembly.
4. 4

   Remove reservoir mounting fasteners
   Remove the 2 mounting bolts or screws securing the reservoir bracket to the inner fender or radiator support using a 7/16" socket or appropriate screwdriver. The mounting hardware typically consists of sheet metal screws or small bolts with washers. Keep hardware if reusing.
5. 5

   Remove old reservoir assembly
   Lift the reservoir and bracket assembly away from the mounting location. Tilt to drain any remaining coolant into the drain pan. Inspect the mounting location for corrosion or damage to the body panel. Clean the mounting surface with a wire brush if surface rust is present.
6. 6

   Prepare new reservoir
   Unpackage the new coolant reservoir and inspect for cracks or shipping damage. Attach the mounting bracket to the reservoir if supplied separately. Ensure the overflow nipple on the reservoir cap or body is clean and free of debris. Check that the reservoir cap vents properly by pressing and releasing the center valve.
7. 7

   Install new reservoir assembly
   Position the new reservoir and bracket assembly in the mounting location, aligning the bracket holes with the existing mounting holes in the inner fender or radiator support. Insert the 2 mounting bolts or screws and tighten securely by hand, then snug with wrench or screwdriver. Do not overtighten into sheet metal.
8. 8

   Connect overflow hose to radiator
   Slide a new hose clamp onto the overflow hose (or reuse existing if in good condition). Push one end of the overflow hose firmly onto the radiator neck overflow tube until it seats fully (approximately 1 inch engagement). Position the hose clamp 1/4 inch from the hose end and tighten securely with flat blade screwdriver.
9. 9

   Connect overflow hose to reservoir
   Route the overflow hose from the radiator to the reservoir, ensuring it follows a gentle upward slope to the reservoir inlet with no kinks or sharp bends. Slide a hose clamp onto the free end, then push the hose onto the reservoir inlet nipple until fully seated. Position and tighten the clamp.
10. 10

    Fill reservoir to proper level
    Add fresh conventional ethylene glycol (green) coolant to the reservoir until the level reaches the COLD FULL mark molded into the reservoir body (typically 1/2 to 2/3 full). Do not overfill. Install the reservoir cap firmly by pressing down and turning clockwise until it stops.
11. 11

    Refill and burp cooling system
    Add conventional ethylene glycol (green) coolant to the radiator through the radiator filler neck until it reaches the base of the filler neck. Start the engine and allow it to reach operating temperature with the radiator cap off. Add coolant as the level drops during warm-up. Watch for coolant circulation and thermostat opening (level will drop suddenly). When level stabilizes and no more air bubbles emerge, reinstall radiator cap securely.

Reassembly

1. Verify all hose clamps are positioned properly and tightened to prevent leaks
2. Confirm reservoir is mounted securely without excessive movement
3. Double-check that overflow hose route does not contact hot engine components or moving parts
4. Wipe down any coolant residue from engine bay surfaces and reservoir exterior

Verification

• Start engine and allow to reach full operating temperature while monitoring for leaks at all hose connections
• Rev engine to 2000 RPM briefly and observe that coolant level in reservoir rises slightly, confirming proper overflow function
• Allow engine to cool completely and verify coolant level in reservoir returns to COLD FULL mark
• Check radiator coolant level when cold; top off if necessary and verify reservoir receives overflow during next warm-up cycle
• Inspect ground under vehicle after overnight cool-down to confirm no coolant leaks have developed

More procedures for this vehicle