UNDERHOOD MAINTENANCE Drive Belts

DRIVE BELTS Two types of Belts are used Two types of Belts are used V-belts because they are shaped like a V. V-belts because they are shaped like a V. Cog style & Plain Cog style & Plain Multi ribbed belts Multi ribbed belts

DRIVE BELTS

PULLEYS AND BELTS Make sure you have the right size belt Make sure you have the right size belt Pitch and Width must be correct Pitch and Width must be correct Tension belt in foot pounds Tension belt in foot pounds Some water pumps turn in opposite direction Some water pumps turn in opposite direction Pg & 234C

PULLEYS AND BELTS The side of the V belt is what grips the side of the pulley. The side of the V belt is what grips the side of the pulley. Example B it will not work the pitch is wrong. Example B it will not work the pitch is wrong. Example C is to wide, does not even fit into the groove. Example C is to wide, does not even fit into the groove. Example D is worn out, it has bottomed out. Example D is worn out, it has bottomed out.

V - Belt & Pulley Problems Belt not alignedPulley worn

V - Belt Adjustment Most new cars have automatic tensioners on them so no adjustment is needed. But the old belts must be checked and tightened. Most new cars have automatic tensioners on them so no adjustment is needed. But the old belts must be checked and tightened.

Belt Adjustment Find the Drive Belt Picture like this one from All Data if you do not know how to adjust it. Thanks All Data for use of the picture.

Belt Adjustment Old cars have many ways to adjust them. Old cars have many ways to adjust them. But they must be checked and tightened. But they must be checked and tightened.

DRIVE BELTS PROBLEMS V Belts Thanks Dayco

DRIVE BELTS PROBLEMS

DRIVE BELTS PROBLEMS Multi ribbed belts APPEARANCE: Each side of belt appears shiny or glazed. In advanced stages, fabric becomes exposed. CAUSE: When in motion, the belt makes contact with an object in its path such as a flange or bolt. This may be caused by improper belt tension or pulley bearing size. SOLUTION: Replace belt and remove the foreign object or, if it can’t be removed, ensure that contact is voided. Check the automatic belt tensioner and ensure proper belt tension. Thanks to Gates for picture and info

DRIVE BELTS PROBLEMS Multi ribbed belts APPEARANCE: Pieces or chunks of rubber material have broken off from the belt. When chunk-out has occurred, a belt can fail at any moment. CAUSE: Chunk-out can happen when several cracks in one area move parallel to the cord line. Heat, age and stress are the primary contributors. SOLUTION: Replace the belt immediately. Thanks to Gates for picture and info

DRIVE BELTS PROBLEMS Multi ribbed belts APPEARANCE: Belt material is sheared off from the ribs and builds up in the belt grooves. CAUSE: There are a number of causes, including lack of tension, misalignment, worn pulleys or a combination of these factors. Pilling is found most frequently in diesel engines, but is not isolated to them. SOLUTION: When pilling leads to belt noise or excess vibration, the belt should be replaced. Accessory brake pulleys should be checked for material buildup between groves. Replace if necessary. Thanks to Gates for picture and info

DRIVE BELTS PROBLEMS Multi ribbed belts APPEARANCE: Belt shows damage to the side with the possibility of breaks in the tensile cord or jagged edged ribs. A thumping or grinding noise may also be heard when running. CAUSE: A foreign object—such as a small pebble—in the pulley can cause uneven wear and cut into the belt. SOLUTION: Replace belt and inspect pulley for foreign objects or damage. Replace pulley if necessary Thanks to Gates for picture and info

APPEARANCE: A belt rib begins separating from the joined strands. If left unattended, the cover will often separate, causing the belt to unravel. CAUSE: Improper belt installation is a common cause of premature failure. One of the outer-most belt ribs is placed outside the pulley groove, causing a belt rib to run without a supporting or aligning pulley groove. SOLUTION: The belt’s life has been severely limited and should be replaced immediately. Ensure all ribs of the replacement belt fit into the pulley grooves. Run the engine. Then, with the engine off and battery disconnected, inspect the belt for proper installation. Thanks to Gates for picture and info DRIVE BELTS PROBLEMS Multi ribbed belts

APPEARANCE: Small, yet visible cracks along the length of a rib or ribs. CAUSE: With continuous exposure to high temperatures, the stress of bending around the pulley leads to cracking. Cracks begin on the ribs and grow into the cord line. As a rule, if three or more cracks appear in a three-inch section of a belt, eighty percent of the life is gone and the belt should be replaced. SOLUTION: Replace & Check tensioner pulley and idler pulley for bearing wear. Replace if necessary. Thanks to Gates for picture and info DRIVE BELTS PROBLEMS Multi ribbed belts

APPEARANCE: Sidewalls of the belt may appear glazed or the edge-cord may become frayed and ribs removed. A noticeable noise may result. In severe cases, the belt can jump off the pulley. CAUSE: Pulley misalignment can be caused by two conditions (see below). Misalignment forces the belt to kink or twist while running, causing premature wear. SOLUTION: Replace the belt and make sure to realign the pulleys. Also check to make sure the pulleys, pulley brackets and shafts are not bent or broken. Thanks to Gates for picture and info DRIVE BELTS PROBLEMS Multi ribbed belts

APPEARANCE: Small pinholes are visible on the backside of the belt. Bumps may be visible and fabric around the holes can be frayed. CAUSE: Rock, gravel or sand is wedged between the belt grooves and pulley ridges. SOLUTION: The belt needs to be replaced to avoid tensile cord separation and possible roadside failure. Thanks to Gates for picture and info

DRIVE BELTS PROBLEMS If You have a squeak and it sounds like a belt try squirting water on it if it goes away you probably need a new belt. If You have a squeak and it sounds like a belt try squirting water on it if it goes away you probably need a new belt. Alignment: make sure it is on right

DRIVE BELTS

Make sure you know how to route the serpentine belt around the pulleys. Make sure you know how to route the serpentine belt around the pulleys.

DRIVE BELTS If the pulley has grooves on it, the side of the belt that has the Ribs will face it. If the pulley has grooves on it, the side of the belt that has the Ribs will face it.

DRIVE BELTS If the pulley is smooth it will face the side of the belt that is smooth. If the pulley is smooth it will face the side of the belt that is smooth.

DRIVE BELT TENSIONER.

1. SPRING: Maintains belt tension at a constant value throughout the operating range. 2. ARM: Connects spring to idler pulley while maintaining proper alignment. 3. INSERT BEARING: Provides angular alignment needed for proper belt tracking. 4. DAMPING ELEMENT (SPRING SUPPORT): Provides additional tensioner damping and load balancing. 5. SPRING HOUSING/SPINDLE: Anchors spring. Arm pivots around the spindle. 6. IDLER PULLEY: Pulley surface is grooved, flat or crowned. 7. PULLEY BOLT: Allows service replacement of pulley & means for lifting arm. 8. DUST SHIELD: Prevents high-pressure spray, foreign material or installation tools from damaging the bearing seal. *Note: Sometimes integrated with pulley bolt. 9. FRONT PLATE: Holds tensioner together. 10. THRUST WASHER: Provides thrust wear surface. Thanks to Goodyear for the picture & info

DRIVE BELT TENSIONER Make sure the tensioner is in good shape. Make sure the tensioner is in good shape.

Idler Pulleys Don’t forget the Idler Pulley. We change out the belt and the tensioner but forget the other pulley’s. Are they whining, check the nylon ones for wear across the surface. All can wear but nylon ones need to be replaced more often. (see picture on previous page)

That’s all folks!!! Thanks to Dayco, Cat, Auto Insite, Gates And AllData For the Pictures