Tachometer Calibration Test
NOTE:
DO NOT
reverse polarity when installing tachometer. Damage to diode and transistor may result.
Connect a calibrated, reliable tach-dwell meter to vehicle ignition system. Run engine at varying RPM. If comparison between tach-dwell meter and vehicle tachometer readings do not fall in the standard range of permissible variation, replace vehicle tachometer. For allowable variation, see TACHOMETER ALLOWABLE VARIATION .
TACHOMETER ALLOWABLE VARIATION
| Engine RPM | (1) RPM Type 1 Tach | (2) RPM Type 2 Tach | ||||
|---|---|---|---|---|---|---|
| 700 | 600-800 | 600-800 | ||||
| 3000 | 2850-3150 | 2900-3225 | ||||
| 5000 | 4750-5250 | 4900-5325 | ||||
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