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Home >> Mercury >> 1995 >> Villager LS >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Overhaul - 4F20E >> Testing >> Stall Speed Test >> Test Procedure
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Test Procedure

  1. Apply service and parking brakes. Connect tachometer or appropriate scan tester to engine, and record RPM reached in each gear selector range (except Neutral) at WOT. Stall speed should be 1800-2100 RPM. If stall speed exceeds specification, ensure engine is mechanically okay and tuned to specification. If engine is okay, remove torque converter and check torque converter one-way clutch for slippage.
  2. If stall speed is too high in "D", "2", "1", the following components may be faulty:
    • Forward Clutch
    • Forward One-Way Clutch
    • Low One-Way Clutch
  3. If stall speed is too high in "R", the following components may be faulty:
    • Low/Reverse Clutch
    • Reverse Clutch
  4. If stall speed is too low in all ranges, the following may be faulty:
    • Engine out of tune
    • Forward one-way clutch
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