In many cases it is possible to remove and install the overrunning alternator pulley while the alternator is still on the engine. The plastic protective cap cannot be re-used after it has been removed from the pulley. A replacement cap is supplied with the new part.
Are all alternator pulleys the same size?
Pulleys must match the appropriate alternator as shown on the list of available pulleys. Alternator shaft sizes are not all identical so a pulley from one alternator may not be interchangeable with a pulley from another.
How do you check a pulley on an alternator?
Rev up the engine to approximately 2000-2500 revolutions per minute (rpm). Then shut it off and listen for a buzzing sound coming from the alternator. If you hear a short buzzing sound (1 to 5 seconds), the pulley’s bearing may have worn out and the overrunning alternator pulley may require replacement.
Does alternator pulley size matter?
Using a smaller pulley will speed the rotor up, and the alternator will produce more power. This won’t effect the ECM or anything else in the vehicle, since top voltage will still be regulated.
Can I just replace alternator pulley? – Related Questions
How does pulley size affect speed?
Pulleys of Different or Same Size
If a smaller pulley turns a larger one, the larger one will turn slower, but with more power available at the shaft. If a bigger pulley turns a smaller one, the smaller one will turn much faster than the bigger one but with less power available at the shaft.
What is the pulley ratio in an alternator?
The first step is to understand how the pulley ratio affects the alternator. Typical original-equipment ratios are around 3 to 1, which simply means the crank pulley is three times the diameter of the alternator’s pulley. Ratios less than 3 to 1 are typically looked at as being underdriven.
Does idler pulley size matter?
#2 An idler pulley is generally spring loaded in engine applications. The size of the pulley doesn’t matter, because the belt doesn’t wrap around the idler, the idler just pushes on the belt between two pulleys to tension the belt.
Do underdrive pulleys add horsepower?
Underdrive pulleys will yield a small increase in horsepower anywhere from 8 to 15 hp. This is accomplished by reducing the amount of power needed to drive the engine accessories that eat up precious horsepower.
How do you calculate alternator rpm?
A simple formula used for this calculation is: RPM = Hz X 120 / number of poles.
What is alternator pulley?
The alternator pulley allows the V-shape or serpentine belt to spin the alternator and is driven by the engine’s accessory drive system. Commonly made from stamped steel or cast aluminum, alternator pulleys are available in two types. One type is grooved for use with a V-type fan belt.
How do I know if my alternator pulley is bad?
If you ever hear growling or whining noises coming from under the hood, you could have alternator problems, which should be checked out by a professional ASAP. This growling or whining sound happens when the belt that turns the alternator’s pulley becomes misaligned or rubs against the side of the pulley.
Can a bad pulley cause alternator problems?
If the idler pulley fails completely, the serpentine belt will likely come off, causing the engine-driven accessories (i.e., alternator, air conditioning compressor, etc.) to stop working.
How long does an alternator pulley last?
The expected life span of a decoupler type pulley, according to the website of the company that manufactures them, is 40,000 to 60,000 miles.
What can burn out an alternator?
A battery that won’t charge properly puts an excessive strain on the alternator that it was never designed to handle and will quickly cause it to fail. A good battery should never drop below 10 volts when cranking, assuming the starter is in good shape and not pulling excessive current.
What causes a noisy alternator?
A Failure of Bearings: Bearings failure is usually the reason why your alternator is noisy. The alternator works in a manner wherein all its moving parts will rotate in order to produce electricity.