Auto Repair Encyclopedia
Timing Belt Replacement |
Sometimes referred to as Timing Belt, Replace Timing Belt, Timing Belt Replace, T Belt, T Belt Replace, Replace t belt, timing gear belt, timing gear belt replace
Driven by the crankshaft, the timing belt keeps internal engine components in sync by causing valves to open and close at the proper time.
In order to maintain the mechanical integrity the engine needs to operate, engine components must be in precise synchronization. If the timing belt is loose or improperly adjusted, it may "jump time" (skipping a tooth or more, usually on the cam gear). This results in a loss of synchronization and engine performance.
In addition, because the timing belt is made from rubber and reinforced with fiber cords, it naturally degrades over time. It should be replaced at scheduled intervals, which vary among car manufacturers, but are usually every 60,000 to 90,000 miles.
In some cases, when the timing belt fails, the engine will simply stop running; replacing the belt will fix the problem.
Some engines cannot tolerate any deviation in precise valve control (e.g. a loose belt, skipped tooth, belt separation, or breakage). In these engines, timing belt failure can have disastrous consequences. These belt-related problems can cause major engine damage, such as damaged pistons and bent valves. The Check Engine Light may illuminate with a fault stored in the computer relating to timing deviation. In extreme cases, the timing belt may be audibly loose and noisy prior to failure; however, a worn belt can fail without warning. Timing belt maintenance and replacement intervals must be followed diligently.
To replace the timing belt, remove the fan belts, pulleys, crankshaft pulley, and timing covers. When replacing the timing belt, the mechanic also inspects components inside the timing cover and, if necessary, replaces oil seals, tensioners, and idler bearings. On certain engines, a water pump replacement should be done at the same time as the timing belt. The timing belt and timing belt idler are considered a unit and should be replaced at the same time.
