Belts and Hoses
Drive belts are made of reinforced, high-tensile strength cords and synthetic rubber. They connect to the engine and transfer power to accessories such as the vehicle’s air conditioning compressor, power steering pump, alternator, etc. Belts come in two different types: The V-belt (cross-section of the belt has a V-shape) and the serpentine belt (also called Poly-V, Poly-Rib, Multi-Rib, and Micro-V belt), which uses multiple Vs for more contact area with pulleys. Serpentine belts are now used on almost all vehicles.
Drive belts provide power to engine-mounted accessories like the power steering pump, air conditioning compressor, mechanical cooling fan, and air-injection pump.
Studies show the chances of a drive belt failure rises dramatically after four years or 36,000 miles for V-belts, and after 50,000 miles for serpentine belts. This doesn’t mean you shouldn’t have your vehicle’s drive belts inspected before then. D & R Intensive Car Care inspects your vehicle’s drive belts every time we change your oil to make sure they’re okay and properly tightened. When checking V-belts, a slipping belt usually has shiny sidewalls commonly referred to as glazing; this is caused by heat from slipping through the pulleys. The glazed condition often causes a chattering, slapping, or squealing noise, and because the glazing hardens the belt, it’s prone to cracking or premature failure. Belt slippage often occurs because of low tension, the wrong belt, grease, or oil. Oil and/or grease on belts will often cause missing chunks or layer separation. The source of the oil or grease needs to be corrected before installing a new belt. A V-belt with any of these conditions should be replaced as soon as possible. On serpentine belts, inspect the belt closely for any cracks in the ribbed area.
A good rule is if the serpentine belt has more than four cracks per inch then it needs to be replaced. Also check the backside of the belt for grooves, fraying, or splitting. Although random cracks across the ribs are a sign of normal belt wear and don’t mean the belt will fail immediately, it’s a good idea to replace the belt the next time your car is serviced.
Many of today’s engines use timing belts, but not all. Some engines still use a timing chain. Timing belts have all but replaced the timing chain and in doing so have taken on many functions. Especially critical with the timing belt is uniformity of the teeth and their spacing. The belt’s teeth are precision-molded from a special rubber compound for good mesh and long life. The belt’s inherent tensile, or stretch-resistant qualities, come from high strength cords that run parallel with the direction of belt travel. Unlike the timing chain, the timing belt has no stretch ability.
The timing belt maintains crankshaft-to-camshaft synchronization and keeping valve operation matched to piston position. On some engines, the belt also drives other components; these include the oil pump, water pump, and balance shafts.
Check your car’s owner’s manual for information on timing belt maintenance. Manufacturers generally recommend a certain mileage for belt replacement; most are 60,000 miles. Unlike drive belts, timing belts cannot be easily viewed therefore making it difficult to tell if they have been changed. If the timing belt is not replaced at the suggested interval, the belt could break leaving you stranded and possibly causing valve damage, a costly repair. It is D & R Car Care’s normal recommendation to replace your timing belt every 60,000 miles, or at the manufacturer’s recommended mileage. We also recommend replacing the timing belt components and any accessory component driven by the timing belt every second timing belt change. The water pump, timing belt sprockets, and tension pulleys are good examples. Check with D & R Car Care if you have questions about your car’s needs for timing belt maintenance.
Coolant hoses include the upper radiator hose, lower radiator hose, heater hoses, and bypass hose (some engines). Coolant hoses are made of reinforced synthetic rubber made to withstand heat, vibration, pressure, and cooling system chemicals.
Coolant hoses provide a flexible connection for coolant flow between the engine and the radiator and the engine and the heater core.
The coolant hoses should be inspected at least twice a year, both in the spring and in the fall. Hose clamp connections should also be checked to ensure that they’re secure and free from leaks. Although hose condition has historically been determined from the outside of the hose, research shows that hoses really begin to break down from the inside out. This process, called electrochemical degradation (ECD), generates fine cracks in the wall of the hose. These fine cracks extend from inside the hose to the outside, close to one or both ends of the hose. Coolant can then seep through these cracks and attack the hose reinforcement. Eventually, the condition worsens to a pinhole leak or a burst hose. Coolant hoses should be replaced at least every four years or more often as needed. It’s also a good idea to change any hoses that connect to a part of the cooling system that’s being replaced. For instance, it’s wise to replace both of the heater hoses when replacing the heater core. If you decide to service your cooling system yourself, use extreme caution. Opening a hot radiator or coolant reservoir/overflow tank can cause severe burns. Be sure that both the engine and cooling system are cool before you begin any heating/cooling system maintenance or repairs. It’s possible that your car may be equipped with an air bleed for the cooling system. Unless the cooling system is bled properly air may stay trapped in the system and cause erratic temperatures, or in extreme cases, engine or cooling system damage. If you’re unsure about any aspect of cooling system service, don’t take a chance. Have your vehicle looked at by a professional service technician at D & R Car Care.