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NAPA Alternator

Choose from over 300 parts within the NAPA Alternators portfolio. These products reflect the most popular applications in the UK market.

NAPA alternators are surcharge-free so come without the added complication of core returns.

Why Replace?
The lifespan of alternators depends heavily on the conditions and climate they are working in. The cranking system of a vehicle gets put under extreme pressure during winter months, resulting in increased demand. Alternators have to work hard due to falling temperatures overnight reducing the available cranking power from the battery. Additionally, the wet and salty road conditions corrode the parts and result in loose or broken connections. Although alternators are designed to cope with the above conditions, any weaknesses are more apparent in winter.

Product Quality
All products are built to meet or exceed OE specifications, this ensures the replacement part will be able to tolerate a large amount of stress from challenging weather conditions.

NAPA Alternators are built, tested and validated to meet or exceed industry standards. They also undergo an end-of-line functionality test. This ensures the quality and reliability of the NAPA products supplied to customers is extremely high.

The Technical Bit
Once the battery has provided electricity to the starter motor to start the vehicle, the alternator generates energy to feed the electrical system and charge the battery. As the vehicle needs more capacity the ECU (engine control unit) sends a signal to the alternator for it to start charging. The alternator has to cope with varying electrical capacity and adjust its charge rate accordingly. These days it is easy for alternators to be misdiagnosed as being faulty if a charging fault is experienced on the vehicle but more often than not, no fault is found with the alternator.

Related Resources

Fixing a Problematic Alternator

Any problems with the alternators can be directly linked to a problem with the battery so it’s important to cover off the below tests and checks. Several issues related to the battery can cause the warming lamp to illuminate on...

Why do rotating products fail in winter?

Winter is the season for rotating electric failure due to the low temperatures resulting in cooler air and damp conditions which cause overnight condensation. This affects the car’s cranking system, making the starter motor work harder and creating a deeper...

Know How - Expert Edition - LIN-controlled Alternators

With Tim Stock Tim is well-known in the automotive aftermarket for his wealth of experience and expertise in all things repair-related. From lending a helping hand to installers through technical support to leading regular seminars, Tim’s name has become synonymous...

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