This procedure covers removal and replacement of the flywheel on a 1966 Chevrolet Corvette with 327ci V8 engine, requiring transmission removal and crankshaft rear seal service.

Warnings

Tools required

Parts

• Flywheel (if damaged or resurfacing exceeds limits) × 1 — Use OEM specification
• Clutch disc × 1 — 10.5 inch diameter for 327 V8
• Pressure plate × 1 — 10.5 inch diameter for 327 V8
• Pilot bearing × 1 — Use OEM specification
• Throwout bearing × 1 — Use OEM specification
• Rear main seal × 1 — 2-piece rope seal for 327 V8
• Transmission input shaft seal × 1 — Use OEM specification
• Flywheel bolts (if reusing shows any damage) × 6 — Use OEM specification
• Thread locker (blue, medium strength) × 1 — Loctite 242 or equivalent

Fluids

• 5W-30 Conventional engine oil — 5 qt

Preparation

1. Park vehicle on level surface and engage parking brake
2. Disconnect negative battery cable
3. Drain engine oil into appropriate container
4. Remove distributor cap and mark distributor position for reinstallation reference
5. Support engine from above using engine support bar or hoist to prevent tilting when transmission is removed

Procedure

1. 1

   Remove driveshaft
   Mark driveshaft-to-differential flange orientation for correct reinstallation. Remove the 4 U-bolt nuts securing the rear U-joint to the differential pinion flange and the U-joint/flange at the transmission output. Separate driveshaft at both ends and remove from vehicle. (Verify C2 driveshaft attachment method.) If the transmission uses a slip-yoke output, plug the transmission extension housing with a clean rag to prevent fluid loss.
2. 2

   Disconnect transmission linkage and components
   Disconnect clutch linkage at the clutch fork and remove clutch return spring. Disconnect speedometer cable from transmission. Remove transmission crossmember mounting bolts. Support transmission with transmission jack before removing crossmember completely.
3. 3

   Remove transmission mounting bolts
   Remove the transmission-to-bellhousing bolts. On 1966 Corvette, there are 4 bolts securing the transmission to the bellhousing. Ensure transmission is securely supported on transmission jack before removing final bolts.
4. 4

   Remove transmission
   Carefully slide transmission rearward on transmission jack, keeping it level and aligned with input shaft. The input shaft must clear the clutch disc and pilot bearing without binding. Lower transmission and move clear of work area. Remove bellhousing-to-engine block bolts and remove bellhousing.
5. 5

   Inspect clutch assembly
   Examine clutch disc for oil contamination, glazing, or wear below minimum thickness. Check pressure plate fingers for wear and uneven height. Check throwout bearing for roughness or noise when spun. Replace clutch components as a complete set if any component shows significant wear.
6. 6

   Remove pressure plate and clutch disc
   Mark pressure plate-to-flywheel orientation with paint or punch marks. Gradually loosen the 6 pressure plate bolts in a star pattern, 1-2 turns at a time to prevent warping. Remove pressure plate and clutch disc together. Note orientation of clutch disc for reinstallation.
7. 7

   Lock flywheel and remove mounting bolts
   Use flywheel holding tool or wedge large screwdriver between flywheel teeth and bellhousing mounting surface to prevent rotation. The 327 V8 flywheel is secured with 6 bolts arranged in a circular pattern. Remove all 6 flywheel bolts using breaker bar or impact wrench. Mark flywheel-to-crankshaft orientation before removal.
8. 8

   Remove flywheel and pilot bearing
   Carefully remove flywheel from crankshaft flange. Flywheel weighs approximately 15-18 lbs. Use pilot bearing puller or slide hammer with internal jaw attachment to extract pilot bearing from crankshaft end. Inspect pilot bearing bore in crankshaft for damage or scoring.
9. 9

   Inspect and service flywheel
   Inspect flywheel friction surface for heat checking, cracks, scoring, or hot spots. Check flywheel ring gear teeth for damage. Measure flywheel runout if dial indicator is available (maximum runout 0.008 inches). Have flywheel resurfaced by machine shop if needed, but do not exceed maximum material removal specification. Clean flywheel bolt holes and friction surface thoroughly with brake cleaner.
10. 10

    Replace rear main seal if needed
    Inspect two-piece rope-type rear main seal for oil leakage. If replacement is required, carefully remove old seal sections from crankshaft and block. Install new rope seal sections per manufacturer instructions, ensuring proper seating and trimming flush with block surface. This is an opportune time to address any rear main seal leakage.
11. 11

    Install new pilot bearing
    Pack new pilot bearing with high-temperature wheel bearing grease. Drive or press new pilot bearing into crankshaft bore until seated flush or to specified depth. Ensure bearing is installed straight and fully seated to prevent input shaft misalignment.
12. 12

    Install flywheel
    Clean crankshaft flange thoroughly with brake cleaner and wire brush. Align flywheel with crankshaft using orientation marks made during removal. Install 6 flywheel bolts with light coat of blue thread locker on threads. Hand-tighten all bolts first. Using flywheel holding tool to prevent rotation, torque flywheel bolts to specification in star pattern, working in multiple passes (first pass 30 lb-ft, second pass 45 lb-ft, final pass 60 lb-ft).
    Torque spec

    Flywheel Bolts95 Nm (70 lb-ft)
13. 13

    Install new clutch assembly
    Place new clutch disc against flywheel with protruding hub side facing transmission (stamped side typically faces flywheel). Insert clutch alignment tool through clutch disc and into pilot bearing to center disc. Position new pressure plate over clutch disc, aligning with orientation marks on flywheel if reusing old pressure plate. Install 6 pressure plate bolts finger-tight.
14. 14

    Torque pressure plate bolts
    Gradually tighten pressure plate bolts in star pattern, alternating bolts and working in multiple passes to pull pressure plate down evenly. Torque to manufacturer specification (typically 30-35 lb-ft for 10.5 inch clutch). Remove clutch alignment tool after all bolts are torqued. Verify clutch disc moves freely with slight side-to-side play.
15. 15

    Install bellhousing and transmission
    Install bellhousing to engine block with new gasket if needed. Lubricate transmission input shaft splines lightly with high-temperature grease. Install new throwout bearing on clutch fork. Position transmission on transmission jack and carefully align input shaft with clutch disc and pilot bearing. Slide transmission forward into bellhousing, ensuring input shaft enters pilot bearing smoothly without forcing. Install transmission-to-bellhousing bolts and torque to specification (typically 50-55 lb-ft).
16. 16

    Complete reassembly
    Install transmission crossmember and torque mounting bolts. Reconnect clutch linkage and adjust clutch pedal free play to specification (typically 1 inch at pedal pad). Install driveshaft, aligning marks made during disassembly. Torque U-bolt nuts to specification. Reconnect speedometer cable. Remove rag from transmission extension housing.
17. 17

    Refill fluids and final checks
    Refill engine with 5 quarts of 10W-30 conventional oil (or period-appropriate viscosity per owner's manual). Reinstall distributor cap. Reconnect negative battery cable. Start engine and check for unusual noises or vibrations. Test clutch engagement and disengagement through full pedal travel. Check for fluid leaks around transmission and rear main seal area.

Reassembly

1. Ensure all driveshaft alignment marks are matched to prevent driveline vibration
2. Verify clutch pedal free play is adjusted to specification before driving
3. Torque all fasteners to proper specifications using star pattern where applicable
4. Replace all crush washers and gaskets during reassembly

Verification

• Start engine and verify smooth idle with no abnormal vibrations
• Test clutch engagement point and verify full disengagement when pedal is depressed
• Drive vehicle and verify smooth clutch operation through all gears with no slipping or chattering
• Check for transmission fluid leaks after test drive
• Verify no unusual noises from clutch or transmission during operation
• Confirm proper clutch pedal free play measurement

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