How to examination a small engine charging system, bombardment & alternator?

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Common Battery Charging System Issues

  • Hearing a click or groan when starting electrical-outset engines
  • Onboard electronics aren't operating properly
  • Battery won't accuse or is draining too quickly

Notation: If you apply a key to offset your lawn mower, snow blower or outdoor power equipment, the small engine includes an electrical charging organisation with a battery and alternator.

Is Your Lawn Mower or Small Engine Battery Dead?

If your backyard mower battery won't hold a accuse, connect it to the charger. If information technology isn't fully charged within viii hours, your battery is dead and you'll need to supplant information technology.

If your lawn mower battery does charge fully, the accuse should non bleed if it is non in use. Troubleshoot continued issues by using a multimeter (service part number 19602) to see if your bombardment drains power while non in use. If it holds the charge through testing, you may have an issue with the alternator.

Alarm: Improper use of the battery and charger can result in an explosion and burn run a risk. Follow the instructions provided by the battery and bombardment charger manufacturers:

  • Always wearable safety spectacles
  • Service batteries in a well ventilated area away from flames or sparks or other ignition sources
  • Practise not tip the battery or remove whatever vent caps

How to Check Alternator on Your Pocket-size Engine

Alternators power the modest engine while it is running, keeping the battery charged by circulating power dorsum through the system.

For the easiest method to cheque your alternator, simply turn on the headlights to your backyard mower or outdoor ability equipment. Then, turn off the engine. If the lights dim, the alternator works. If non, it doesn't.

If this isn't an pick, follow these instructions on how to test alternators.

Attach a Multi-meter to Your Engine

Connect multi-meter (service part number 19602) to your engine based on your alternator type.

You tin can determine this by the color of the wires - either AC volts or DC amps. These wires extend beneath the blower housing and are connected to the stator. For Briggs & Stratton® engines, you can match upward the wires and alternator's configuration with your Alternator Identification Chart. Once you find a match, find the AC/DC setting in the upper correct-manus corner.

If you need aid in identifying the fashion of alternator installed on your engine, review the Alternator Specifications (PDF), download your illustrated parts list or contact a Briggs & Stratton dealer or the equipment manufacturer.

Once you have your proper setting identified:

  • Set the multi-meter dial to Air conditioning VOLTS or DC AMPS.
  • Insert the black multi-meter lead into the tester's COM receptacle.

    • For Air conditioning VOLTS, connect the other end to basis, such every bit an engine commodities or cylinder fin.
    • For DC AMPS, connect the other end to the battery's positive terminal. (NOTE: The battery must exist grounded to the equipment frame of the engine cake to create a complete circuit).

  • Insert the red lead on the multi-meter into the tester's receptacle (labeled AC VOLTS or AMPS).
  • Connect the cerise lead to the advisable stator output wire. See illustrations below to see that your multi-meter is properly attached.

Have the Multi-meter Voltage Reading

  • Kickoff the engine and let information technology run for several minutes to reach its operating temperature.
  • Using a tachometer (service part number 19598), set up the engine test speed and check the reading on the multi-meter. Unless specified, all tests should be carried out with the engine running at 3600 RPM.
  • Compare your multi-meter reading against the recommended voltage (amps or volts) listed in the using the Alternator Identification Chart, Alternator Specifications or equipment manual.
  • Turn off the engine and disconnect the tester from your equipment.

If your results do not lucifer the specifications, you will need to supplant your alternator stator if it is an Ac VOLT alternators. For DC Amp alternators, replacing the stator, diode or regulator may exist required. Otherwise, please contact a dealer.

Alarm: Always read the engine and equipment manual(s) before starting, operating, or servicing your engine or equipment to avoid personal injury or property damage. Encounter an authorized dealer if you are unsure of any procedure or have additional questions.

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