By 1976, the United States economy was on the mend from the 1973–1975 global economic recession. The recession, which had been caused in part by the 1973 oil crisis, had caused gas prices to soar which, in turn, had made automotive manufacturers begin re-evaluating the types of vehicles they were manufacturing.
It had led to the end of the big-block engine era for Chevrolet, and had further influenced the decision being made by automotive manufacturers everywhere to increase fuel economy at all costs – even if it meant a loss in horsepower as a result. However bad the prognosis had looked just a year earlier, 1976 had seen President Jimmy Carter come into office and with him, an eventual economic stimulus package that would re-strengthen a diminished economy.
Despite the economic hardships felt around the world, the 1976 Stingray had arrived on the heels of one of Corvette’s most successful sales years ever. The commercial success of the 1975 Corvette coupe (but not the convertible) had strengthened Chevrolet’s resolve to do away with the roadster option and focus solely on producing the best edition of their popular sports car possible. It was a gamble that would prove to pay off.
Stylistically, the 1976 Corvette was the best looking of the C3 Corvettes to date. While the changes to the exterior were minor, they were significant from an aesthetics standpoint.
To start, the air-extractor vents were removed from the rear deck. These vents, which had been part of the C3 Corvette since 1968 (they served as the exhaust mechanism for Corvette’s Astro-Ventilation system,) were eliminated along with the ventilation system itself.
Similarly, the 1976 Corvette’s hood no longer featured a cowl flap. The former hood’s cowl flap had become the center of consumer complaints which stated that the assembly whistled loudly during vehicle operation.
In place of the cowl flap, a simpler system was developed that rammed in airflow through a duct that ran forward over the radiator support to pick up some of the outside air that fed the radiator.
Even though the cowl-induction system had been eliminated for 1976, the intake grille remained for another year, and would not be deleted until 1977.
Moving to the rear of the Corvette, Chevrolet introduced two different styles of rear bumper/fascia assemblies. The first fascia was actually a carryover from the 1975 model year and featured the word “CORVETTE” in a large font that filled the width of the surface area between the rear headlights. The second, which was introduced in 1976, featured the word “CORVETTE” in smaller, recessed letters.
Perhaps the most notable change for 1976 was the re-introduction of the aluminum wheels that had first been introduced in 1973. Listed as option RPO YJ8, the set of four aluminum wheels (the 1973 option had actually included a fifth full size wheel as a spare) sold at an additional cost of $299.00 for the set, and included a conventional steel spare wheel/tire assembly. The wheels were manufactured by Kelsey Hayes in Mexico and could be identified by the source and build location information etched on their inside surface.
The interiors of the 1976 Corvette were largely unchanged from the previous year with one, notable exception. The interior now featured a four-spoke, “sport” steering wheel, though it was an option not well received by Corvette enthusiasts due mostly to the fact that the new steering wheel was the same as those being installed on the subcompact Chevy Vega GT, along with a number of other Chevrolet models that year.
Another change to the Corvette’s interior that was more widely accepted was the inclusion of the custom interior trim package (including leather seats) as part of the car’s base package.
Beneath the car, a partial steel subsection was added to the forward body structure. This steel under pan was added in an effort to increase the car’s rigidity and to act as a heat shield/insulator between the Corvette’s catalytic converters and the vehicle cockpit. While the catalytic converter was a concern to some engineers, it was actually a benefit to others. As a result of the catalytic converter being installed, the horsepower rating of the 1976 Corvette actually increased slightly.
The L48 engine saw an increase of 15 horses, pushing its total horsepower to 180bhp. The L82 increased up to 210bhp. Unfortunately, the L82 engine was not offered in California in 1976 (and 1977) because it did not meet the state’s tougher emissions standards. Four-speed manual transmissions were also banned out west for those same model years.
Interestingly, an automatic transmission was the only option available to Californians in 1976 (and 1977). However, it wasn’t the Turbo Hydra-Matic 400 that had been previously used behind all Corvette engines. Instead, Chevrolet mandated use of the less robust TH 350 automatic transmission. This choice was made because product planners felt that using the more expensive 400 transmission was overkill, especially given the limited amount of power that the L48 engine produced. The TH 400 remained the transmission of choice whenever a Corvette equipped with the L82 was ordered with an automatic transmission
Elsewhere, there were other mechanical revisions to the C3 that also helped improve performance, helped reduce weight and further helped the horsepower boost experienced on the 1976 Corvette.
Power steering and power brakes became standard on all 1976 Corvettes midway through production (though 173 early-production Corvettes hit the streets without power steering). Chevrolet introduced a lighter (by approximately 13 pounds) Delco Freedom battery as standard piece of equipment.
The Corvette also featured the aforementioned modified cowl induction, which was as much a functional benefit to the car’s overall performance as it was an aesthetic revision to the Corvette’s hood. Since pull air through an intake that was located in front of and above the radiator instead of at a more restrictive cowl located near the windshield, the 1976 Corvette could now breathe more easily.
Unfortunately for consumers, Corvette’s price had risen again for 1976. It had increased over the previous model years because of the sharp inflation that had plagued consumers since the start of the global energy crisis in 1973. In 1976, consumers could purchase a base coupe (without any options) for $7,604.85. However, if the car were purchased with a full complement of options (as many were), it was possible to spend more than 10 grand (including ancillary charges) for the first time in Corvette’s history.
Still, although the price of the Corvette was at an all-time high, the new Corvette was still in high demand, as reflected in the fact that Chevrolet sold 46,558 units that year, breaking the previous sales record set in 1969.
It has been debated that this continued increase in Corvette sales in 1976 was a direct result of the energy crisis earlier in the decade. Many automotive manufacturers had eliminated their performance-car production lines completely, forcing consumers to turn to Chevrolet and the 1976 Corvette as a result. While some critics have speculated that this was the primary reason for the Corvette’s sales strength that year, there was still no denying that the Corvette was a unique and satisfying sports car – even at the higher price point.
Two-door convertible/coupe, front engine, rear wheel drive
St. Louis, Missouri
Uniconstruction: fiberglass reinforced plastic (FRP or “fiberglass”) body, backboned by a steel cage outlining the passenger compartment. Principal members – underbody, front and rear end assemblies, dash panel and hinge pillars are bonded, riveted, or bolted together and to each other. Hood is plastic with bonded plastic reinforcement. Coupe: two removable roof panels and removable rear window. Frame: all welded, full length, ladder construction with 5 crossmembers. Side Rails and intermediate crossmembers box section; front crossmember box girder section. Eight body-mounting points.
Type and Description: Independent, SLA type, coil springs with center mounted shock absorbers, spherical joint steering knuckle pivots.
Front Coil Springs
Make & Type
10.27 x 3.80; 130.84 x 0.606
Front Stabilizer Bar
Hot rolled steel
Suspension – Back
Type and Description: Full Independent rear suspension with frame-anchored differential unit. Position of each wheel established by three links: tubular axle drive shafts, transverse strut rods, torque control arms. Vertical suspension loads taken by transverse leaf springs. Built-in camber adjustment at strut rod inner ends.
Rear Leaf Springs
Number of Leaves
Variable rate 9-leaf
Chrome carbon steel
Length, width, height
48.60 x 2.25 x 2.121
Caliper Disk – 4 Wheel Dual Hydraulic with Pressure Differential and Warning Light
Delco Moraine, vacuum power unit; integral
Drum diameter, front (in.):
11.75 x 1.25
Drum diameter, rear (in.):
11.75 x 1.25
Swept Drum Area Effective area:
Wheels & Tires
Wheels & Tires Specs
Short spoke spider, welded steel
15″ x 8.00
15″ x 8.00
GR70 x 15B — Blackwall Steel Belted Radial
GR70 x 15B — White Stripe Steel Belted Radial
GR70 x 15B — White Letter Steel Belted Radial
20 psi (cold), 30 psi (hot)
20 psi (cold), 30 psi (hot)
Steering Specs – Manual Steering
Recirculating ball nut
Integral, recirculating ball nut with hydraulic pressure provided from a vane type pump.
Wheel Diameter (in.)
Turns, Stop to Stop
37 ft. (outside front), 38.6 ft. (outside front)
1976 Corvette Exterior Dimensions
Exterior Dimensions (Coupe)
Interior Dimensions (Coupe)
Total Body Width:
Front Track Width:
Rear Track Width:
Min. Ground Clearance
2 – Driver & Passenger
Curb Weight (lbs)
Interior Passenger Volume (cu. ft)
Interior Trunk Volume (cu. ft)
Fuel Capacity (gallons):
4.0 (capacity of crankcase less filter – refill)
4.5 (capacity of crankcase refill with filter change)
Coolant capacity without heater (qts.)
12 Volt, 78 Plates, 3,500 Watts for Standard
12 Volt, 90 Plates, 4,000 Watts for Heavy Duty
Vehicle Assembly Location. S – St. Louis, Missouri
4XXXXX (Eighth thru Thirteenth Digits)
Plant Sequence Numbers.
The last six digits begin at 400001 and run thru 446558, accounting for 46,558 Corvette Coupes built in 1976. Each Vehicle Identification Number (VIN) is unique to an individual car. There is documented evidence that the final VIN for the 1976 Corvette ended in 446567, nine more units than the published total of 46,558.
1976 Corvette Vehicle Serial Number Plate
For all 1976 Corvettes, the location of the Vehicle Identification Number (VIN) is stamped on a plate attached to the left front body hinge pillar. (See Figure 1 below.)
1976 Corvette Body Number & Point Plate
On the driver’s side upper left-hand door hinge pillar.
A01 – Body build date code
A – Designates the Month (See Chart Below).
A – Aug., 1975B – Sep., 1975C – Oct., 1975D – Nov., 1975E – Dec., 1975F – Jan., 1976, G – Feb., 1976H – Mar., 1976 I – Apr., 1976 J – May, 1976 K – June, 1976 L – Jul., 1976, M – Aug., 1976
01 – Designates the Day of the Month.
19V – Interior Trim code. 19V – Black (Vinyl)
10L – Exterior Color Code. 10 – Classic White
Codes were often followed by the letter L, but some trim plates had an exterior code preceded by the number 9 with no letter L following.
1976 Corvette Factory Options
Base Corvette Sport Coupe
Custom Interior Trim
Rear Window Defogger
Optional Rear Axle Ratios
350ci, 210hp Engine
4-Speed Manual Trans, Close Ratio
Turbo Hydra-Matic Automatic Transmission
Tilt Telescopic Steering Column
White Stripe Steel Belted Tires, GR70x15
White Letter Steel Belted Tires, GR70x15
AM-FM Radio, stereo
Heavy Duty Battery
Map Light (on rearview mirror)
California Emission Test
Aluminum Wheels (4)
Base Corvette Sport Coupe (1YZ37)
The base price of the 1976 Chevrolet Corvette Coupe without any optional equipment.
A 350 cubic inch, 180 horsepower engine, 4-speed wide ratio manual transmission, vinyl interior trim, and T-tops were included in the base price.
The only engine-transmission combination that was available in California was the base 350 cubic inch, 180 horsepower engine with the M40 Turbo Hydra-Matic automatic transmission.
Listed as separate options originally, power brakes (J50) and power steering (N41) were included in an increased base price in 1976.
Custom Interior ( — )
Optional interior trim upgrade that included a number of custom modifications to the base interior.
The custom interior trim includes leather seat trim, wood-grain accents and carpet trim on door panels, wood-grain accents on the console, and cut-pile carpeting.
Power Windows (A31)
Factory installed power driver and passenger windows.
Rear Window Defroster (C49)
An optional rear window forced air defogger.
This option used glass heating elements instead of forced air and the naming convention changed from “defroster” to “defogger”.
Air Conditioning (C60)
Factory installed four-season air-conditioning.
System includes evaporator, blower, condenser, receiver-dehydrator, refrigerant (freon) tank, air intake assembly and duct assembly for both systems.
Includes an integrated heater.
Gymkhana Suspension (FE7)
An optional, heavier-duty suspension system for higher levels of performance.
Included a stiffer front sway bar and stiffer springs.
There were no restrictions on ordering this option – it could be ordered with any engine/transmission combination.
Optional Rear Axle Ratio – Rear axle ratio selection.
Power Brakes (J50)
Vacuum power assisted brakes; includes dual circuit master cylinder.
All 1976 Corvettes had power brakes.
350ci, 210hp Engine (L82)
Optional higher-output, small block V-8 engine.
4-Speed Manual Transmission, Close Ratio (M21)
A close ratio version of the M20 Muncie 4-speed manual transmission.
The gear ratios for the RPO M21 Close Ratio 4-Speed Manual Transmission are: 1st Gear – 2.20:1, 2nd Gear – 1.64:1, 3rd Gear – 1.28:1, 4th Gear – 1.0:1 (Direct).
M21 was a no-cost option but required the optional L82 engine.
The Turbo Hydra-Matic Automatic Transmission consisted of a 3-element hydraulic torque converter and compound planetary gear set. It was equipped with the following gear ratios: 1st Gear – 2.48:1, 2nd Gear – 1.48:1, and 3rd Gear – 1.00:1.
The M40 Turbo Hydra-Matic Automatic Transmission was a no-cost option with the base 350 cubic inch, 180 horsepower engine, but cost $134.00 with the optional L82 engine.
Tilt Telescopic Steering Column (N37)
An optional, adjustable steering column and tilt-angle adjustable steering wheel.
The Telescopic Steering Column changes the drivers distance from the steering wheel by literally telescoping the steering wheel closer to or further away from the vehicle operator.
Power Steering (N41)
Hydraulically assisted power steering.
Magnets were added to power steering units to attract and collect metallic debris caught in the power steering fluid.
All but 173 Corvettes came equipped with power steering in 1976.
White Stripe Steel Belted Tires, GR70x15 (QRM)
Standard size tires with a special 3/8″ wide white sidewall stripes.
White Letter Steel Belted Tires, GR70x15 (QRZ)
Standard size tires with special raised white lettering.
AM-FM Radio, Stereo (U58)
A standard/stock dealer installed Corvette radio.
The radio received broadcast in FM 2-channel stereo, FM monaural, and AM monaural.
16-transistor 9-diode circuitry.
Fixed height rear antenna.
The 1976 Corvette was the last of the era to require a unique Delco radio due to the available console depth.
In 1976, 1,203 Corvettes were ordered without a radio.
AM-FM Radio (U69)
A standard/stock dealer installed Corvette radio.
The radio receives broadcast in FM monaural, and AM monaural.
16-transistor 9-diode circuitry.
Fixed height rear antenna.
The 1976 Corvette was the last of the era to require a unique Delco radio due to the available console depth.
In 1976, 1,203 Corvettes were ordered without a radio.
Heavy Duty Battery (UA1)
Optional, heavier-duty battery with increased cranking amps/capability.
General Motors “freedom” battery, a new sealed and maintenance-free unit, was included with all 1976 models.
Map Light (on rearview mirror) (UF1)
Light mounted on inside rearview mirror.
California Emission Test (YF5)
An assembly line emissions test to conform with California registration requirements.
Aluminum Wheels (4) (YJ8)
Included four aluminum wheels and a conventional steel spare.
The aluminum wheels were originally expected for arrival as an option on the 1973 Corvette.
The wheels were developed by Kelsey Hayes in Mexico.
The wheels can be identified on their inside surfaces as to source and build location.
The carburetor air induction system was revised in 1976. Previously, air was drawn in at the rear of the hood, producing a howling or whining sound in the interior of the Corvette. The source point for the air was moved forward, enabling air to be pulled into the engine compartment over the radiator.
Two bumper styles were used on the 1976 Corvette – one featured the Corvette logo in small, recessed letters. The other featured larger letters that were surface mounted (not recessed.)
The 1976 hood is unique to the model year.
Engineers put a partial steel underbelly in the forward section of the 1976 Corvette for added rigidity, weight reduction, and to better isolate the cockpit from heat generated by the car’s catalytic converters.
Astro Ventilation was eliminated from the Chevy Corvette in 1976. As part of the deletion of this option, the vents on the rear deck (just aft of the back window) were deleted.
A new “sport” steering wheel was introduced for the 1976 Corvette that was shared with the Chevy Vega (and other Chevy models.) Because it was not unique to the Corvette, it was not well received by Corvette enthusiasts.
Some of the late production 1976 Corvettes utilized interior components from the 1977 Corvette model.
Corvette sales in Canada for the 1976 model year included 4,289 units.
1976 Corvette Recalls
Make: CHEVROLET Model: CORVETTE Model Year: 1976 Manufacturer: CARDONE INDUSTRIES, INC. Mfr’s Report Date: MAY 07, 2003 NHTSA CAMPAIGN ID Number: 03E032000 NHTSA Action Number: N/A Component: SERVICE BRAKES, AIR:DISC:CALIPER Potential Number of Units Affected: 15899
REMANUFACTURED REAR BRAKE CALIPERS, PART NOS. 18-7019, 18-7020, 16-7019, AND 16-7020, MANUFACTURED FROM FEBRUARY 1, 2002, TO APRIL, 25, 2003., AND FOR USE ON 1965 THRU 1982 CHEVROLET CORVETTES. THE SUBJECT BRAKE CALIPERS WERE MANUFACTURED USING IMPROPERLY MANUFACTURED PISTON SEALS. THESE SEALS ARE INTENDED TO PREVENT FLUID LEAKAGE BETWEEN THE CALIPER HOUSING AND THE PISTONS. THESE BRAKE CALIPERS ARE FOR USE ONLY ON 1965 THRU 1982 CHEVROLET CORVETTE VEHICLES. THIS RECALL DOES NOT INVOLVE GENERAL MOTORS CORPORATION OR ANY OF ITS PRODUCTS
UNDER THESE CONDITIONS, THE VEHICLE OPERATOR MAY NOT BE ABLE TO STOP THE CAR, POSSIBLY RESULTING IN A VEHICLE CRASH.
CARDONE WILL NOTIFY ITS CUSTOMERS AND ALL UNSOLD INVENTORY WILL BE REPURCHASED AND WILL PROVIDE A FULL REFUND TO CUSTOMERS. OWNER NOTIFICATION IS EXPECTED TO BEGIN DURING MAY 2003. OWNERS WHO TAKE THEIR VEHICLES TO AN AUTHORIZED DEALER ON AN AGREED UPON SERVICE DATE AND DO NOT RECEIVE THE FREE REMEDY WITHIN A REASONABLE TIME SHOULD CONTACT CARDONE AT 215-912-3000.
ALSO, CUSTOMERS CAN CONTACT THE NATIONAL HIGHWAY TRAFFIC SAFETY/ ADMINISTRATION’S AUTO SAFETY HOTLINE AT 1-888-DASH-2-DOT (1-888-327-4236).
Make: CHEVROLET Model: CORVETTE Model Year: 1976 Manufacturer: HONEYWELL INTERNATIONAL, INC. Mfr’s Report Date: OCT 19, 2007 NHTSA CAMPAIGN ID Number: 07E088000 NHTSA Action Number: N/A Component: EQUIPMENT Potential Number of Units Affected: 121,680
CERTAIN HONEYWELL FRAM RACING BRAND HP4 AND HP8 OIL FILTERS THAT WERE MANUFACTURED FROM MAY 25, 2006, THROUGH SEPTEMBER 14, 2007, AND SOLD FOR USE AS REPLACEMENT EQUIPMENT FOR VEHICLES LIST ABOVE. THE AFFECTED FILTERS ARE MARKED WITH A DATE CODE A61451 THROUGH A72571 SEQUENTIALLY. THE DATE CODE AND PART NUMBER APPEAR ON THE FILTER HOUSING. FRAM RACING HP4 AND HP8 OIL FILTERS NOT BEARING A DATE CODE IN THIS RANGE ARE NOT AFFECTED BY THIS RECALL. THE GASKET OF THE OIL FILTER BECOMES MORE PLIABLE UNDER HIGH TEMPERATURES AND PRESSURES.
THIS CONDITION MAY CAUSE INADEQUATE SEALING AND LOSS OF ENGINE OIL, POSSIBLY RESULTING IN A FIRE.
HONEYWELL WILL REPLACE THE AFFECTED OIL FILTERS FREE OF CHARGE. THE RECALL BEGAN DURING NOVEMBER 2007. OWNERS CAN CONTACT FRAM CUSTOMER SERVICE TOLL-FREE AT 1-800-890-2075.
CUSTOMERS MAY CONTACT THE NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION’S VEHICLE SAFETY HOTLINE AT 1-888-327-4236 (TTY: 1-800-424-9153); OR GO TO HTTP://WWW.SAFERCAR.GOV.
1976 Corvette Service Bulletins
1976 Corvette Common Issues
1976 Corvette Maintenance Schedule
The time or mileage intervals indicated on this website are intended as a guide for establishing regular maintenance and lubrication periods. Sustained heavy duty or high speed driving, or driving under adverse conditions may require more frequent servicing.
Additional Maintenance and Lubrication
In addition to the items listed above, it is also recommended that the following items are inspected every 300 miles or 2 weeks, whichever comes first:
Check Tire Pressure
Check Battery Water Level
Check Oil Level In Engine
Remove air cleaner and block throttle and choke in wide open position. Hook up starter remote control cable and insert compression gauge firmly in spark plug port. Whenever the engine is cranked remotely at the starter, with a jumper cable or other means, the distributor primary lead must be disconnected from the negative post on the coil and the ignition switch must be in the “ON” position. Failure to do this will result in a damaged grounding circuit in the ignition switch.
Crank engine through at least four compression strokes to obtain highest possible reading. Check and record compression of each cylinder. If one or more cylinders reads low or uneven, inject about a tablespoon of engine oil on top of pistons in low reading cylinders (through spark plug port.) Crank engine several times and recheck compression. If compression comes up but does not necessarily reach normal, rings are worn. If compression does not improve, valves are burnt, sticking or not sealing properly. If two adjacent cylinders indicate low compression, the cause may be a head gasket leak between the cylinders. Engine coolant and/or oil in cylinders could result from this defect
The adjustments described apply to all carburetors used, except as noted. All adjustments are made with the engine at normal operating temperature
Idle Speed (1972-1976)
The idle stop solenoid requires two idle speed settings. The curb idle speed is normal engine idle speed, the low idle speed is set for conditions when the solenoid is de-energized, as when the ignition is turned off. This prevents engine run-on. Idle speed adjustments are made with the engine at normal operating temperature, with the air cleaner on, choke open, air conditioning off, and fuel tank hose from vapor canister disconnected (on later models). Set parking brake and block driving wheels. Disconnect electrical connector at idle stop solenoid. With automatic transmission in Drive, or manual transmission in neutral, turn low idle screw to obtain low idle speeds of 500 rpm, reconnect electrical connector to solenoid and crack throttle slightly, to extend solenoid plunger. Then turn approximately 600 rpm for automatic transmission models in Drive, or approximately 850 prm for manual transmission models in neutral. Shut off engine and reconnect fuel tank to vapor canister
Idle Mixture (1972-1976)
The idle mixture is factory preset and the screws are capped with plastic limiter caps. These caps allow about one full turn for adjustment. If more is required remove the caps or break off the tabs with needle nose pliers. Adjusting the idle mixture is done with the engine running at normal operating temperatures, with the air cleaner on, choke open, air conditioning off, and fuel tank hose from canister disconnected. Set the parking brake and block the driving wheels. Put automatic transmission in Drive; manual transmission in neutral. Turn in or out one idle mixture screw at a time to obtain smoothest, fastest idle speed; then adjust the other screw to make engine run even smoother and faster. A basic starting point for adjusting screws is four turns out from fully in position with needle just touching seat. Readjust idle speed if necessary. Reconnect fuel tank hose from canister
Idle Speed and Mixture – Holley 2300
All adjustments are same as previously described except as follows: On models equipped with idle stop solenoid, adjust idle stop solenoid screw to give 1000 rpm, then adjust idle mixture adjusting screw to specified rpm. Turn idle mixture screw in (leaner mixture) until engine speed drops 20 rpm, then turn out 1/4 turn. Disconnect lead at idle stop solenoid (throttle level will rest against regular stopscrew.) Adjust this stopscrew for idle speed of 500 rpm. Do not change setting of idle stop solenoid stopscrew or idle mixture screw
Fast Idle (1966-1976)
With the transmission in neutral, position the cam follower on the high step (2nd step, 1971-1972) of the fast idle cam. Adjust fast idle screw of Rochester carburetors to obtain recommended fast idle speed. Bend fast idle lever on Holleys. On 1970-72 models, disconnect transmission controlled spark solenoid
With slow idle speed correctly adjusted, fully open choke and make sure fast idle cam follower is off steps of cam. With dashpot fully compressed, adjust for 1/16″ clearance between dashpot plunger and throttle lever
Remove the air cleaner and check to see that choke valve and rod more freely. Disconnect choke rod at choke lever. Check choke adjustment by holding choke valve closed and position rod so that it contacts stop. If necessary, adjust rod length by bending rod at offset. Bend must be such that rod enters choke lever hole freely and squarely. Connect rod at choke lever and install air cleaner
Air Injection Reactor (A.I.R.) – Description and Operation
The A.I.R. system is used to burn the unburned portion of the exhaust gases to reduce its hydrocarbon and carbon monoxide content. The system forces compressed air into the exhaust manifold where it mixes with the hot exhaust gases. The hot exhaust gases contain unburned particles that complete their combustion when the addition air is supplied.
The system consists of: An air pump, diverter valve, check valve(s), AIR pipe assemblies and connecting hoses and fittings. Carburetors and distributors for AIR engines are made to be used with the system and should not be replaced with components intended for use with engines that do not have the system.
The air pump is a two-vane pump which compresses fresh filtered air and injects it into the exhaust manifold. The pump consists of: a housing, centrifugal filter, set of vanes that rotate about the centerline of pump housing bore, the rotor, and the seals for the vanes. The centrifugal filter is replaced by first removing the drive belt and pump pulley; then pulling filter off with pliers. Care should be taken to prevent fragments from entering the air intake hole. NOTE: A new filter may squeal when first put into operation. Additionally, GREAT CARE should be taken in working on the compressor as the aluminum used is quite soft and thin. The air pump is operating satisfactorily when the air flow from it increases as engine speed increases.
The air hoses should be replaced only with hoses which are designed for AIR system use, as no other type hoses can withstand the high temperature.
Check and Adjust Dwell
Start engine then check ignition dwell. With engine running at idle, raise the adjustment screw window and insert an Allen wrench in the socket of the adjusting screw. Turn the adjusting screw as required until a dwell reading of thirty degrees is obtained. A two degree variation is allowable for wear. Close access cover fully to prevent the entry of dirt into the distributor. If a dwell meter is not available, turn adjusting screw clockwise until engine starts to misfire, then turn screw one-half turn in the opposite direction to complete adjustment.
Slowly accelerate engine to 1500 rpm and note dwell reading. Return engine to idle and note dwell reading. If dwell variation exceeds specifications, check for worn distributor shaft, worn distributor shaft bushing or loose breaker plate.
Remove distributor cap, clean cap and inspect for cracks, carbon tracks and burned or corroded terminals. Replace cap where necessary. Clean rotor and inspect for damage or deterioration. Replace rotor where necessary. Replace brittle, oil soaked or damaged spark plug wires. Install all wires to proper spark plug. Proper positioning of spark plug wires in supports is important to prevent cross-firing. Tighten all ignition system connections. Replace or repair any wires that are frayed, loose or damaged
Disconnect the distributor spark advance hose and plug the vacuum source opening. Start engine and run at idle speed. Aim timing light at timing tab. The markings on the tabs are in two degree increments (the greatest number of markings on the “A” side of the “Q”). The “O” marking is TDC (Top Dead Center) and the BTDC settings fall on the “A” (advance) side of the “O”. Adjust the timing by loosening the distributor clamp and rotating the distributor body as required, then tighten the clamp, and recheck timing. Stop engine and remove timing light and reconnect the spark advance hose.
Inspect each plug individually for badly worn electrodes, glazed, broken or blistered porcelains and replace plugs where necessary. Clean serviceable spark plugs thoroughly, using an abrasive-type cleaner such as sand blast. File the center electrode flat. Inspect each spark plug for make and heat range. All plugs must be of the same make and number. Adjust spark plug gaps to .035 in. using a round feeler gauge. If available, test plugs with a spark plug tester. Inspect spark plug hole threads and clean before installing plugs. Install spark plugs with new gaskets and torque to specifications. Connect spark plug wiring.
Transistorized Distributor (H.E.I. System)
There are no moving parts in the ignition pulse amplifier, and the distributor shaft and bushings have permanent type lubrication, therefore no periodic maintenance is required for the magnetic pulse ignition system.
Distributor (Breaker Point System)
Check the distributor centrifugal advance mechanisms by turning the distributor rotor in a clockwise direction as far as possible, then releasing the rotor to see if the springs return it to its retarded position. If the rotor does not return readily, the distributor must be disassembled and the cause of the trouble corrected.
Check to see that the vacuum spark control operates freely by turning the movable breaker plate counter-clockwise to see if the spring returns to its retarded position. Any stiffness in the operation of the spark control will affect the ignition timing. Correct any interference or binding condition noted.
Examine distributor points and clean or replace if necessary. Contact points with an overall gray color and only slight roughness or pitting need not be replaced. Dirty points should be cleaned with a clean point file. Use only a few strokes of a clean, fine-cut contact file. The file should not be used on other metals and should not be allowed to become greasy or dirty. Never use emery cloth or sandpaper to clean contact points since particles will embed and cause arcing and rapid burning of points. Do not attempt to remove all roughness nor dress the point surfaces down smooth. Merely remove scale or dirt. Clean cam lobe with cleaning solvent, and rotate cam lubricator wick end (or one-hundred-eighty degrees as applicable). Replace points that are burned or badly pitted.
Where prematurely burned or badly pitted points are encountered, the ignition system and engine should be checked to determine the cause of trouble so that it can be eliminated. Unless the condition causing point burning or pitting is corrected, new points will provide no better service than the old points.
Check point alignment then adjust distributor contact point gap to .019″ (new points) or .016″ (used points). Breaker arm rubbing block must be on high point of lobe during adjustment. If contact points have been in service, they should be cleaned with a point file before adjusting with a feeler gauge.
Check distributor point spring tension (contact point pressure) with a spring gauge hooked to breaker lever at the contact and pull exerted at 90 degrees to the breaker lever. The points should be closed (cam follower between lobes) and the reading taken just as the points separate. Spring tension should be 19-23 ounces. If not within limits, replace. Excessive point pressure will cause excessive wear on the points, cam and rubber block. Weak point pressure permits bouncing or chattering, resulting in arcing and burning of the points and an ignition miss at high speed.
Install rotor and distributor cap. Press all wires firmly into cap towers.
Battery and Battery Cables
The top of the battery should be clean and the battery hold-down properly tightened. Particular care should be taken to see that the top of the battery is kept clean of acid film and dirt. When cleaning batteries, wash first with a dilute ammonia based or soda solution to neutralize any acid present and then flush off with clean water. Keep vent plugs tight so that the neutralizing solution does not enter the cell. The hold-down bolts should be kept tight enough to prevent the batter from shaking around in its holder, but they should onto be tightened to the point where the battery case will be placed under a severe strain.
To ensure good contact, the battery cables should be tight on the battery posts. Oil battery terminal felt washer. If the battery posts or cable terminals are corroded, the cables should be cleaned separately with a soda solution and wire brush. After cleaning and before installing clamps, apply a thin coating of a petrolatum to the posts and cable clamps to help slow corrosion.
If the battery has remain undercharged, check for loose or defective fan belt, defective alternator, high resistance in the charging circuit, oxidized regulator contact points, or a low voltage setting. If the battery has been using too much water, the voltage output is too high.
Inspect for deteriorated or plugged hoses. Inspect all hose connections. On engines with closed element air cleaners, inspect crankcase ventilation filter and replace if necessary. On engines with open element air cleaners, remove flame arrestor and wash in solvent then dry with compressed air.
Check the brake fluid regularly, for as the brake pads wear the level will drop rapidly. It should be replenished only with the recommended fluid. Check disc brake assemblies to see if they are wet; it would indicate a leaking cylinder.
Disc brakes do not need periodic adjustments; they are self adjusting. The pads should be replaced when the friction material gets down to 1/16″. This is when the groove in the center of the pad is gone. Check by removing wheel and looking directly into caliper.
Clutch Pedal Play
Check clutch action by holding pedal 1/2″ from floor and move shift lever between first and reverse several times, with engine running. If shift is not smooth adjust clutch. Free play with pedal released is approx. 1-1/4″ to 2″ and 2″ to 2-1/2″ for heavy duty.
At clutch lever near firewall remove clutch return spring. To decrease clutch pedal free play remove clutch pedal return spring and loosen lower nut on clutch pedal rod; take up play with upper nut. Continue until proper play is obtained, then securely tighten top nut and replace spring. To increase pedal play work nuts in opposite sequence.
Clutch Adjustment (1975-1982)
Disconnect the clutch return spring at the cross shaft. Push the clutch lever until the pedal is against the rubber stop under the dash. Loosen the two shaft locknuts and push the shaft until the throwout bearing just touches the pressure plate spring. Tighten the top locknut toward the swivel until the distance between it and the swivel is 0.4″. Tighten the bottom locknut against the swivel. The pedal free travel should not be 1-1/2″.
Disconnect control linkage at carburetor throttle lever. Hold carburetor throttle lever in wide position. Pull control linkage to wide open position. (On vehicles equipped with automatic transmission, pull through detent.) Adjust control linkage to freely enter hole in carburetor throttle lever. Connect control linkage at throttle lever.
Throttle Linkage Adjustment (Powerglide)
Remove air cleaner, disconnect accelerator linkage at carburetor. Disconnect accelerator return and trans. road return springs. Pull upper rod forward until transmission is through detent. Open carburetor wide open, at which point ball stud must contact end of slot in upper rod. Adjust swivel on end of rod if necessary.
Pull detent switch driver to rear until hole in switch body lines up with hole in driver. Insert a 3/16″ pin through hole to depth of 1/8″, and loosen mounting bolts. Open throttle fully and move switch forward until lever touches accelerator lever. Tighten mounting bolt and remove pin.
EGR Valve Check
A rough idling engine may be caused by a malfunction of the valve. Check by pinching vacuum hose to carburetor with engine idling. If idling smooths out, the valve should be removed for cleaning or replacement if something appears to be broken.
Lubrication – Engine Oil
The car should be standing on level ground and the oil level checked with the dipstick. Withdraw the dipstick, wipe it with a clean rag, replace and withdraw again. The mark made by the oil on the lower end of the dipstick will indicate the oil level. If necessary, oil should be added through the filler cap. Never let the oil level fall so low that it does not show at all on the dipstick. If in doubt, it is better to have a bit too much oil than too little. Never mix oils of different brands, the additives may not be compatible.
Engine Oil Drain and Replacement
Place a pan under the oil pan drain plug and remove plug. Be sure pan is of a large enough capacity to hold the oil. Move pan under filter and remove filter by turning if counterclockwise. Clean gasket surface of cylinder block. Coat gasket of new filter with engine oil. Thread filter into adapter. Tighten securely by hand. Do not overtighten filter. Remove drop pan.
Remove drain pan. Inspect oil pan drain plug gasket and replace if broken, cracked, or distorted. Install drain plug and tighten. Fill crankcase to required level with recommended oil. Operate engine at fast idle and check for oil leakage.
Check fluid level with engine idling, transmission in neutral and engine at normal operating temperature. Add fluid as needed to bring level to mark. Do not overfill.
Every 12,000 miles or sooner, depending on service, remove fluid from sump and add new fluid. Operate transmission and check fluid level. Every 24,000 miles the transmission sump strainer of the Turbo Hydra-Matic transmission should be replaced.
Raise car on lift, clean dirt and grease from area around the filler plug. Plug is located on side of transmission case. Remove plug and place finger tip inside hole. The oil should be just about level with the bottom edge of the hole. Add oil as needed, using a plastic syringe.
Change cam lubricator end for end at 12,000 mile intervals. Replace at 24,000 mile intervals.
With the car standing level, clean dirt and grease from area around filler plug. Remove plug and place finger tip inside hole. The oil should be just about level with the bottom edge of the hole. Add oil, with a plastic syringe, as needed.
1976 Corvette Dealers Sales Brochure
Download this 1976 Corvette Dealers Sales Brochure for a quick look at the features of the car.