Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1979 Triumph SpitfireFACTORY OEM SERVICE PROCEDURE
Alternator Output Test
- Disconnect multi-socket connector and remove molded cover from rear of alternator. (Cover may be pierced with a probe on some models in order to ground the field winding brush and by-pass the regulator.) Provide a test circuit as illustrated.
- Start engine and run to give 1, 500 alternator RPM (approximately 650-800 engine RPM). Test circuit bulb should be out.
- Increase engine speed to 2500-3, 000 RPM to give 6, 000 alternator RPM. Adjust variable resistor so voltmeter reads 14 volts and note ammeter reading equal to the nominal output rating for the appropriate alternator. If readings are not correct, alternator requires overhaul or replacement.NOTE: Do not connect variable resistor across battery for longer than is necessary to complete the test.
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.