How to test a minor engine charging system, bombardment & alternator?

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Mutual Bombardment Charging System Issues

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

Note: If y'all use a key to start your lawn mower, snow blower or outdoor ability equipment, the small engine includes an electric charging system with a battery and alternator.

Is Your Lawn Mower or Modest Engine Battery Dead?

If your backyard mower battery won't hold a charge, connect it to the charger. If information technology isn't fully charged within 8 hours, your battery is expressionless and you'll need to replace it.

If your backyard mower battery does charge fully, the charge should not drain if it is not in apply. Troubleshoot connected problems by using a multimeter (service part number 19602) to encounter if your battery drains ability while non in use. If it holds the charge through testing, yous may have an issue with the alternator.

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

  • E'er vesture rubber glasses
  • Service batteries in a well ventilated area away from flames or sparks or other ignition sources
  • Practice not tip the battery or remove whatsoever vent caps

How to Check Alternator on Your Small Engine

Alternators power the modest engine while it is running, keeping the bombardment charged by circulating power back through the organisation.

For the easiest method to check your alternator, simply plough on the headlights to your lawn mower or outdoor power 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.

Adhere a Multi-meter to Your Engine

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

You can make up one's mind this by the colour 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, y'all can match upwards the wires and alternator'south configuration with your Alternator Identification Chart. Once you find a match, notice the Air conditioning/DC setting in the upper correct-hand corner.

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

One time you accept your proper setting identified:

  • Prepare the multi-meter punch to AC VOLTS or DC AMPS.
  • Insert the black multi-meter atomic number 82 into the tester's COM receptacle.

    • For AC VOLTS, connect the other end to ground, such as an engine bolt or cylinder fin.
    • For DC AMPS, connect the other terminate to the battery's positive terminal. (Note: The battery must be grounded to the equipment frame of the engine cake to create a complete circuit).

  • Insert the cherry-red pb on the multi-meter into the tester'due south receptacle (labeled Air-conditioning VOLTS or AMPS).
  • Connect the red pb to the appropriate stator output wire. Run across illustrations below to see that your multi-meter is properly fastened.

Take the Multi-meter Voltage Reading

  • Start the engine and let it run for several minutes to accomplish its operating temperature.
  • Using a tachometer (service part number 19598), set the engine test speed and bank 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 match the specifications, you will demand to supplant your alternator stator if it is an AC VOLT alternators. For DC Amp alternators, replacing the stator, diode or regulator may be required. Otherwise, please contact a dealer.

WARNING: Always read the engine and equipment manual(due south) before starting, operating, or servicing your engine or equipment to avoid personal injury or belongings damage. Run across an authorized dealer if you are unsure of any process or have additional questions.

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