GM Firebird 1967-1981 Repair Guide



See Figures 1 through 5

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Fig. Fig. 1: There are typically 3 types of accessory drive belts found on vehicles today

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Fig. Fig. 2: An example of a healthy drive belt

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Fig. Fig. 3: Deep cracks in this belt will cause flex, building up heat that will eventually lead to belt failure

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Fig. Fig. 4: The cover of this belt is worn, exposing the critical reinforcing cords to excessive wear

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Fig. Fig. 5: Installing too wide a belt can result in serious belt wear and/or breakage


Inspect the belts for signs of glazing or cracking. A glazed belt will be perfectly smooth from slippage, while a good belt will have a slight texture of fabric visible. Cracks will usually start at the inner edge of the belt and run outward. All worn or damaged drive belts should be replaced immediately. It is best to replace all drive belts at one time, as a preventive maintenance measure, during this service operation.


See Figures 6 and 7

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Fig. Fig. 6: When inspecting the accessory drive belt tension, press down on the belt at the mid-point between the two accessory pulleys

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Fig. Fig. 7: While using a prybar to tension the accessory drive belt, tighten the adjusting bolt 1 / 2 in. at the halfway point or 1 / 4 in. if the distance is 7-10 in. If the deflection is found to be too much or too little, loosen the mounting bolts and make the adjustments.

Check the drive belts every 7,500 miles or 6 months for incorrect tension. Determine belt tension at a point halfway between the pulleys by pressing on the belt with moderate thumb pressure. If the distance between the pulleys (measured at the center of the pulley) is 13-16 in., the belt should deflect

Before you attempt to adjust any of your engine's belts, you should take an old rag soaked in solvent and clean the mounting bolts of any road grime which has accumulated there. On some of the harder-to-reach bolts, an application of penetrating oil will make them easier to loosen. When you're adjusting belts, especially on late model V8's with air conditioning and power steering, it would be especially helpful to have a variety of socket extensions and universals to get to those hard-to-reach bolts.

When adjusting the air pump belt, if you are using a prybar, make sure that you pry against the cast iron end cover and not against the aluminum housing. Excessive force on the housing itself will damage it.


To remove a drive belt, simply loosen the accessory being driven and move it on its pivot point to free the belt. Then, remove the belt. If a belt tensioner is used, push (rotate) the tensioner using a 15mm socket, and remove the belt.

Take care as not to bend the tensioner when applying torque. Damage to the tensioner will occur. Maximum torque to load belt should not exceed 30 ft. lbs.

It is important to note, however, that on engines with many driven accessories, several or all of the belts may have to be removed to get at the one to be replaced.