You have no items in your shopping cart.
Back to All Blog Posts

Troubleshooting Ideas for Aircraft Alternator Problems

An aircraft’s alternator is the piece of equipment that serves as the root provider for an aircraft’s total electrical needs. Without a properly functioning alternator, an aircraft’s battery can’t properly charge and could leave an aviator grounded until the problem is resolved.

At Air Power, Inc. we specialize in providing our clients with quality aircraft engines and parts. If your customers come to you with the need for a new alternator or related part, we have the supply on hand to help you keep your customer’s aircraft in prime condition.

However, before completely switching out alternators for customers, let’s take a closer look at the true signs that the alternator is their source of trouble and how you or your customers can troubleshoot the source of their issue for the most accurate repair or replacement.

Signs Your Alternator is in Trouble

If an aircraft experiences some of the following issues, they are a red flag that an alternator is on the verge of failure:

  • Low or no output
  • Stalling engine
  • Discharge indication on an ammeter. These should usually have zero charges with a functioning alternator
  • Declining load meter
  • Low-bus-voltage/alternator-out annunciators

How can You Troubleshoot Your Customer’s Alternator Problems?

When the alternator warning light pops up on an aircraft’s dashboard, it’s important for owners and mechanics alike to remember that this warning light doesn’t always mean that the alternator is the engine part with a problem.

So in order to save an owner the stress of returning an alternator to a mechanic only to realize there is no fault found, here are some ways from the expert manufacturers of Hartzell that can help them troubleshoot their alternator’s problem before having to dig deeper into the mechanics of the aircraft.

Get the Tools of the Trade

In order to perform most troubleshooting techniques, an individual must invest in a Calibrated Volt-Ohm Meter. Our recommendation is to avoid VOMs made with stainless steel as they don’t provide the magnetism that some troubleshooting tests require.

Start With Recycling Switches

Recycle your alternator switch to determine if low or no output to your battery is resulting from the alternator. After switching on your Master and Alternator switches, use your VOM to measure the output. Based on the type of system you have, the following measurements mean that an alternator is in trouble:

  • Less than 13.5 volts for a 12V
  • Less than 25.5 volts for a 24V

Test Magnetic Pull

After your Master and Alternator switches are on, you could place a metal scale on the alternator chassis. A magnetic pull without alternator output showing on your VOM means that there is a problem with the alternator itself.

Measure Field Voltage and Test Field Resistance

Measure your field voltage with your VOM. It should read 75% bus. If it’s lower or zeroes, it’s time for your customers to bring in the alternator.

Use the VOM against your alternator’s field wire to test the field resistance. Your aircraft’s 24-volt alternator should have this reading at 8-12 ohms. Any higher or lower, there could be issues with the alternator’s brushes or brush assembly.

Inspect Grounds With VOM

Check the grounds between your alternator and the aircraft’s frame. If your reading is less than 0.2 ohms, take the aircraft in for inspections and necessary repairs.

Meet Your Customer’s Alternator Needs With Air Power, Inc.

If your aircraft repair shop is constantly in the market for alternators and alternator parts, join up with Air Power, Inc. for a partnership that ensures your shop receives the necessary parts it needs on time.

Our website updates allow our customers to view our stock in real-time and gain a clear understanding of when they will receive their product.

Contact us today to learn more about our services or peruse our website and start making a mass order now.

Write a Comment Close Comment Form