SECTION 11

CHASSIS SHEET METAL

CONTENTS OF THIS SECTION

Figure Index
General Description
Hood Assembly
Radiator Grille
Front End Sheet Metal
Assembly Manual




FIGURE INDEX

Fig. 1 - Hood Hinge
Fig. 2 - Hood Lock
Fig. 3 - Hood Locking Plate
Fig. 4 - Hood Assembly
Fig. 5 - Hood Adjustment
Fig. 6 - Radiator Grille
Fig. 7 - Baffle Assembly
Fig. 8 - Radiator Support to Frame Attachment
Fig. 9 - Underside of Fender Extension
Fig. 10 - Fender Skirt Extension
Fig. 11 - Front Fender Removal
Fig. 12 - Dash Leg Support
Fig. 13 - Front End Sheet Metal
Fig. 14 - Sheet Metal Adjustment

Chassis Sheet Metal Index

The fenders, grille and surrounding sheet metal form an integrated frame work, which is attached to the body and mounted at a central rubber insulated point on the front cross member of chassis frame. The front and rear skirts and the three piece baffle has been replaced by a heavy ribbed, deep drawn one piece skirt which forms a solid box structure with the fender. The skirt is jointed to the fender by a brace, at the rear, to the wheel opening flange and is solidly supported by the dash leg, cowl side panel, body side rail and the tie bar and radiator support.

Three widely spaced cross members maintain alignment and rigidity across the front end. The grille to bumper filler panel connects the fender skirts and fender extensions, a reinforcement spans the grille header line, and a fender-to-fender "U" channel tie bar is riveted through gussets to the radiator core support side channels and serves as the main cross beam supporting the front end structure.

The radiator core support is center mounted to an angle bracket which is welded to the integral front suspension cross member. This type of mounting eliminates the separate radiator support cross member and serves as a base for the filler panel center reinforcement and the hood lock plate support.

The one piece hood, has the lock plate bracket attached to the hood ornament and is riveted to the hood front flange. This arrangement of parts is formed to the front contour of the hood and adds considerable stiffness to the hood panel. Two rods are attached diagonally across the reinforced front corners and draw the panel up tight against the reinforcing center bracket. The radiator upper baffle is attached to the hood at the rear of the hood ornament and spans the arch of the hood, forming an inflexible box structure in combination with the center bracket and diagonally reinforcing rods. The rear edge of the hood is flanged and is weld reinforced with a three piece reinforcement. The two end pieces of the reinforcement are flared for added rigidity at this area.

The new designed hood hinges assure uniform hinge operation through interlocking gear teeth cut concentric with the lever pivots of each hinge. A common attachment to the rigid hood reinforcement eliminates independent hinge action. The hood in any open position, has its weight supported by springs which are attached at both ends to the gear linked levers of the operating mechanism. Through true counter balancing and not over-center counter balancing the shift of the hood weight to the rear and the mechanical advantage of the double acting hood springs permit the use of lighter springs and results in a wider hold open position.

An improved safety catch and self-locking mechanism virtually eliminates the unlocked hood danger. The safety catch and the hood catch are piloted through a hole in the lower lock plate. This prohibits any sliding action of the safety catch. The lock permits only a downward movement of the hood while the car is in motion and provides positive locking at all intermediate positions down to the completely closed position.

The wrap around front bumper ends are attached to the fenders at brackets bolted to the fender extension-to-fender flange. In addition, two bumper support bars to frame are provided at each side. This attachment prevents bumper rattle but still permits sufficient side mounting freedom to take full advantage of the center mounting of the front end assembly.

Service Operations

HOOD ASSEMBLY

Hood Hinge

Removal

1. Prop the hood in the extreme open position and place protective covering over cowl panel and fenders. (figure 1)
2. Scribe position of hinge attachment on hood rear reinforcement and remove two bolts.
3. Scribe position of hinge attachment on cowl wall and remove two bolts and hinge.
   

Installation

1. Seal hinge attaching holes at cowl wall with body caulking compound.
2. Align hinge attaching parts within scribe marks and install 'bolts.
3. Remove protective covering.
   

Hood Lock and Locking Plate

The hood lock, figure 2, is attached to the lock reinforcement with two bolts and a sheet metal screw. The locking plate, figure 3, is attached to the grille reinforcement with two bolts and with one bolt to the spacer assembly. The locking plate holes are slotted to provide a lateral adjustment of the locking plate.

Hood Ornament Assembly

The hood ornament assembly is attached with three bolts to the hood.

Hood Emblem

The hood front emblem is attached to the hood with bolts and speed nuts. Hood Lacing The hood lacing is retained by spread snap clips which are inserted into holes provided in the top of the cowl.

Hood Assembly

Removal

1. Prop hood in open position, then place protective covering at top of cowl and on fenders (fig. 4).
2. Scribe position of hinge attachment on hood rear reinforcement.
3. Carefully remove attaching bolts at hinge to hood. Care must be used to prevent hood from dropping and damaging surrounding parts.
4. Remove hood from vehicle.
   

Installation

1. Protect top of cowl and fenders with covering.
2. Place hood in position over hinges and loosely install bolts.
3. Prop hood in open position, and place hinge to hood attaching plate within scribe marks and tighten bolts.
4. Adjust if necessary and remove protective covering and prop.
   

Adjustment

An up or down or vertical adjustment of the hood is provided through slotted holes at the cowl attaching point. Lateral and longitudinal adjustments are provided through the oversized holes at the hinge to hood attaching point (fig. 5).

Hood Filler Panel and Rod

The hood filler panel is attached with two rivets at each side to the flange of the hood. In addition, it is attached with four rivets to hood lock reinforcement. A seal is provided between the filler panel and the hood. The hood rods which run diagonally from in front of the filler panel to each side of the lock reinforcement are also attached with rivets.

Hood Rear Reinforcement

The hood rear reinforcement is riveted to the side flanges of the hood and is provided with an anti-squeak pad at center line of the hood.

Hood Bumpers Three stationary hood bumpers are located on each side at the fender to fender skirt attaching flange. In addition, two adjustable bumpers are provided on each side, one at the cowl and the other at the radiator., grille reinforcement bar.

Radiator Grille and Baffles

Radiator Grille Removal

1. With the hood open, remove bolts at each upper corner attaching grille reinforcement to fender flange ( fig. 6). NOTE: Bumper has been removed for photographic purposes.
2. Remove two bolts attaching spacer assembly and lock plate to grille reinforcement.
3. Under the fender, at each side, remove two bolts attaching grille to fender skirt and fender extension.
4. Working between the grille and radiator remove bolts attaching grille lower flange to filler panel.
5. Remove grille from vehicle. NOTE: The grille outer and lower bars are screw retained and are accessible after the grille has been removed. The radiator grille header bar is attached by nuts and bolts to the front flange of the hood.
   

Installation

1. Align grille in opening with attaching holes and install bolts attaching grille lower flange to filler panel.
2. Under the fender, install bolts attaching grille to fender skirt and fender extension at each side.
3. Install grille to spacer assembly and lock plate to grille reinforcement bolts.
4. Install bolts at each upper corner of grille reinforcement to fender flange. NOTE: Make sure adjustable hood bumpers are installed to grille reinforcement at the outer corners.
   

Filler Panel

The filler panel may be removed with or without the radiator grille in the vehicle.

Removal

1. Remove front bumper.
2. Remove four bolts at each side, from under filler panel, attaching filler panel flange to fender extension and fender skirt.
3. Remove one bolt attaching filler panel to radiator support.
4. Between the grille and radiator core at the lower edge of the grille flange remove five bolts attaching grille and spacer assembly to filler panel and filler panel center reinforcement.
5. Remove filler panel from vehicle.
   

Installation

1. Align filler panel with holes in attaching panels and install bolts attaching grille to filler panel and filler panel center reinforcement.
2. Install bolts attaching filler panel to radiator support, fender extension and fender skirt.
3. Replace front bumper. Baffle Assembly
   

Removal

1. Open hood and from under the fender remove five sheet metal screws attaching baffle to fender skirt.
2. Remove two sheet metal screws attaching baffle to tie bar. NOTE: Figure 7 shows the baffle, the grille, bumper and horn have been removed for photographic purposes.
3. Remove four bolts attaching baffle to radiator support. NOTE: Upper two bolts also retain horn. Regulator and horn relay is attached to the back of the left hand baffle. Light wiring harness must also be disengaged and ground wire attached to the baffle removed, when removing left hand baffle.
4. Remove two baffle to filler panel attaching bolts and remove baffle.
   

Installation

1. Align baffle with attaching holes and from under filler panel install baffle to filler panel bolts.
2. Install baffle to radiator support bolts and baffle to tie bar screws.
3. Install baffle to fender skirt attaching screws.

Tie Bar and Radiator Support The radiator support is riveted to the tie bar and with the radiator may be removed as an assembly from the vehicle without disturbing the front end sheet metal. The attachment of the radiator core to the radiator support varies with the six and eight cylinder engine. The six cylinder engine radiator core is mounted in front of the tie bar and the eight cylinder engine has the core mounted in back of the tie bar.

Removal

1. Raise the hood and disconnect upper and lower radiator hoses at the radiator and drain radiator. Remove oil cooler lines from base of radiator on Powerglide models.
2. Remove three bolts at each side, attaching radiator to support. Remove radiator core. NOTE: Each radiator core to support attaching bolt may or may not be shimmed. Check location of shims for installation purposes.
3. Remove two screws at each side attaching tie bar to fender skirt also remove two baffle to tie bar upper screws. NOTE: The tie bar is shimmed at the fender skirt attaching point. Check location and number of shims at attaching point.
4. Remove four screws from each side, attaching baffle to radiator support. NOTE: Upper two bolts at each baffle also retain horns to radiator support. Lay horns out of way.
5. From under vehicle straighten out tabs of lock plate and remove nuts from support bolts (fig. 8).
6. Remove lock plate, two plates and cushion, then remove radiator core support and tie bar from vehicle. CAUTION: A pad and shims are inserted between the radiator core support and front cross member. Note the number of shims for installation purposes.
   

Installation

1. Place shims and cushion of front cross member and position radiator core support and tie bar to place. From under the vehicle install plates, cushion, lock plate and nuts to bolts and torque nuts to 3 or 4 ft. lbs. and lock in place with lock plate tabs.
   
2. Install screws attaching baffle and horns to radiator support and tie bar.
3. Replace shims and install bolts attaching tie bar to fender skirt. NOTE: Check anti-squeak at this area before installation and replace if necessary.
4. Position radiator core in support with proper shims at bolt locations. Install bolts loosely.
5. Shift position of radiator in support, allowing 3/4" clearance between radiator core and engine fan and tighten attaching bolts. NOTE: Slotted radiator support frame attaching holes allow movement of the core for engine fan to core clearance. A compensating adjustment, which is available through oversize holes in the frame bracket, may be necessary at the radiator support to chassis frame attachment to acquire the 3/4" core to fan clearance.
6. Connect upper and lower radiator hoses. Replace oil cooler lines to base of radiator on Powerglide models and refill radiator.
   

Fender Extension and Bumper Bar

Removal

1. Under the fender extension remove three bolts attaching extension to the filler panel and one bolt attaching extension to fender skirt.
2. Remove intermediate bumper bracket at frame and bumper. NOTE: Figure 9 shows the fender extension from under the vehicle. The intermediate bumper support bar has been removed for photographic purposes.
3. Remove five bolts attaching extension and bumper support to fender and remove extension and bracket assembly. NOTE: It is not necessary to remove the parking light or bumper face bar.
   

Installation

1. Align fender extension and bumper bracket with attaching holes and install bolts and lockwashers attaching the assembly to the fender.
2. Install bolts and lockwashers attaching extension to filler panel and bolt attaching fender extension to fender shirt.
3. Install bumper to frame intermediate bracket.
   

Fender Skirt Extension

Removal

1. At the rear of the front fender, inside the wheel house opening, remove three metal screws attaching skirt extension to fender skirt (fig. 10).
2. Under and at the rear of the fender, as indicated by arrows, remove extension attaching screws at outside flange of fender and at the chassis frame side member.
3. Remove extension from vehicle.
   

Installation

1. Check extension seal at fender side and install new seal if necessary.
2. Position extension and install retaining screws at skirt, chassis frame and fender flange.

Front Fender

Removal

1. Place protective covering over door and cowl panel.
2. Remove radiator grille from vehicle.
3. Disconnect wiring harness at plastic connector on skirt leading to headlights and parking lights.
4. Remove two bolts attaching tie bar and fender skirt to fender (fig. 11). NOTE: Check shims and their location at this area for installation purposes.
5. Remove fender to cowl and fender to body side rail bolts at the rear of the fender. Observe shim arrangement at these two locations for installation purposes.
6. Remove bolts attaching fender extension and bumper bar to fender.
7. Under and at the rear of the fender, remove bolt attaching skirt extension to fender flange.
8. Along the top fender flange, remove bolts attaching fender to skirt.
9. Remove bolt attaching skirt support to fender.
10. Carefully remove fender from vehicle.
    

Installation

1. Inspect anti-squeak strip and replace if necessary, then place fender in position on vehicle.
2. Align fender to tie bar attaching holes, loosely install proper number of shims and attaching bolts.
3. Align fender to cowl and fender to body side rail holes, loosely install shims, washers and bolts.
4. Install fender to fender skirt bolts at fender top flange.
5. Install fender extension and bumper bar to fender bolts.
6. Install fender skirt extension to fender bolt at fender lower flange.
7. Replace bolt attaching skirt support to fender.
8. Install radiator grille and align fender with body sheet metal and grille, then tighten cowl to fender, body side rail to fender and tie bar to fender bolts. If necessary, add shims at these locations to correct alignment.
9. Make necessary electrical connections and remove protective covering.
   

Front Fender and Skirt

Removal

NOTE: Certain locations have shims specified as required for adjusting purposes, therefore, shims should be replaced as removed at these locations at installations. In addition, check condition of all seals, Raps and anti-squeak strips at fender attaching points.

1. Disconnect head lights, parking light and head light ground (attached to baffle, on left side). Remove wiring harness from clips on fender skirt. On right side fender and skirt removal, remove heater hoses from clip on fender skirt.
2. Remove radiator grille from vehicle.
3. At rear of fender, remove bolt attaching fender to cowl. NOTE: Observe location of shims and washer for installation purposes.
4. Remove bolt securing fender to body side rail at lower inside rear edge of fender. Note shim and washer arrangement for installation purposes.
5. Under fender at rear of wheel opening, remove screw securing skirt extension reinforcement to chassis side member.
6. Remove two bolts attaching fender to fender skirt and tie bar. NOTE: Observe location and number of shims for installation purposes.
7. From under front of fender, remove bolts attaching fender to fender extension and bumper support and bolts attaching baffle to fender skirt.
8. At the rear of the engine compartment, remove screws attaching fender skirt to dash leg support (fig. 12).
9. Pull hood down slightly to allow maximum clearance at rear of fender and disengage fender and skirt from support.
10. Lift fender assembly up and out to remove from vehicle. The fender extension and fender skirt extension are left on the vehicle.
11. Remove headlight and parking light from fender. NOTE: Chevrolet script name is attached with spring nuts to the fender, and the fender molding used on 2400 series is attached with bolts and nuts.
    

Installation

1. Check all seals, hood bumpers, skirt flaps and anti-squeak at fender attaching location and replace if necessary.
2. Install headlight and parking light to fender, script name or molding may also be installed at this time.
3. Place protective covering over door and cowl and place fender and skirt in position and align fender skirt to dash leg support and tie bar and skirt attaching holes and loosely install shims and screws. NOTE: Exercise care when placing fender on vehicle to prevent damage to surrounding finish areas.
4. Align fender to cowl and fender to body side rail holes and then loosely install prescribed shims, washers and bolts at attaching points.
5. Install screw attaching skirt extension reinforcement to chassis side member.
6. Install fender to fender extension and bumper support bolts, also install fender skirt to baffle bolts.
7. Install fender skirt extension to fender skirt bolts.
8. Close hood and align fender with door, hood and grille, shim if necessary and tighten all attaching bolts. NOTE: Fender and skirt may be adjusted up or down at the cowl attachment and in or out at the body side rail attachment. An additional adjusting point is provided at the tie bar to fender attachment through the use of shims.
9. Install radiator grille and connect headlight and parking light wiring harness. Install headlight ground wire to baffle (on left side fender installations). Install heater hoses to right fender skirt.
10. Remove protective covering.

Removal

1. Place protective covering over cowl and door panels, then remove the hood.
2. Disconnect positive cable from battery and remove wiring harnesses from skirts, headlights, parking lights, horns, regulator horn relay and headlight ground attachment to left baffle.
3. Drain radiator and disconnect upper and lower radiator hoses and on Powerglide models disconnect the coolant lines leading to the base of the radiator core.
4. Remove heater hoses from clip on fender skirt. NOTE: To lessen the weight of the front end sheet metal assembly, the radiator may be removed at this point.
5. At the cowl, remove the fender to cowl attaching bolts. NOTE: Observe shims and washer locations for reassembly purposes.
6. Under the rear of the fender remove the fender to body side rail attaching bolts. Observe shim and washer arrangement at these locations for installation purposes.
7. Remove bolts attaching fender extension and bumper support to fender and fender skirt.
8. Remove bumper from vehicle.
9. Under the front of vehicle, remove nuts attaching tie bar and radiator support assembly to chassis frame cross member bracket. NOTE: Observe shim, plate and cushion arrangement at this point for installation information.
10. Lift front end sheet metal from vehicle. Figure 13 shows front end sheet metal removed from vehicle.
    

Installation

1. Tape cushion and shims in place at radiator support to frame cross member attaching point. Place protective covering over doors and cowl.
2. Check all anti-squeak and replace where necessary. Check flaps on fender skirt and replace if necessary.
3. Position front end sheet metal on vehicle. Make sure radiator support to cross member bolts are through frame holes.
4. Loosely install cushion, plates, lock plate and nuts to radiator support bolts.
5. Loosely install fender to cowl and fender to body side rail bolts. NOTE: Replace shims and washers at these locations as predetermined at disassembly.
6. Install fender skirt to dash leg support bolts.
7. Install fender extension and bumper support to fender and fender skirt bolts.
8. Align sheet metal with door and cowl, then tighten bolts at fender to cowl, fender to body side rail and radiator support to frame.
9. Replace bumper and make all electrical connections. Install wiring harness to fender skirt.
10. Install radiator to radiator support, hook up all hose connections and refill radiator. Install heater hoses to fender skirt.
11. Install hood, remove protective covering and check alignment of hood and doors with front end sheet metal. NOTE: If adjustment of Front End Sheet Metal is needed, adjust as outlined in Front End Sheet Metal Adjustment.
    

Front End Sheet Metal Adjustment

The front end sheet metal is provided with four adjusting points (fig. 14). The fender to cowl attaching point allows through shimming an up or down adjustment at the rear. The fender to body side rail allows a lateral adjustment at the rear through shimming. In addition, shimming at the radiator support to chassis frame cross member provides an up or down adjustment of the front of the sheet metal. Oversize holes at this location also provide a fore or aft and lateral adjustment. Further lateral adjustment is available for the front of the fenders by shimming at the tie bar to fender attaching points. To adjust, loosen bolts and nuts on one or both sides, depending on the needed adjustment, shim at the described locations and retighten bolts.

Assembly Manual