Cold Start Device Diagnosis: Notes

1985 Mercury Topaz LS, 2D Sedan, 2.0 HSECTION Notes
  1. Engine must be at normal operating temperature. Rotate CSD lever clockwise to stopper. Use photoelectric tachometer (Rotunda 99-0001) to check engine RPM.
  2. Engine speed must be 1450-1550 RPM. If not, check injection pump timing. See Figure . Check cold start device to verify proper operation. See Cold Start Device Operation table.
    COLD START DEVICE OPERATION

    Engine Temp. °F (°C) Injection Pump Timing Engine RPM
    Below 45 (7) 8° BTDC 1450-1550
    45-68 (7-20) 5° BTDC 1050-1350
    Over 68 (20) 0° TDC 725-775
  3. Apply 20 in. Hg of vacuum to CSD diaphragm. CSD lever should move 1.1" (28 mm). If not, and vacuum diaphragms are not leaking, replace injection pump.
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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.
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