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Piston Inspection

SPECIAL TOOL(S)

G04626834Courtesy of FORD MOTOR CO.
Scraper, Piston Ring Groove
303-D033 (D81L-6002-D) or equivalent
CAUTION: Do not use a caustic cleaning solution or a wire brush to clean the pistons or damage can occur.
  1. Clean and inspect the (1) ring lands, (2) skirts, (3) pin bosses and the (4) tops of the pistons. If wear marks, scores or glazing is found on the piston skirt, check for a bent or twisted connecting rod.
    Fig 1: Identifying Ring Lands, Skirts & Pin Bosses
    G04626835Courtesy of FORD MOTOR CO.
  2. Use the Piston Ring Groove Scraper to clean the piston ring grooves.
    • Make sure the oil ring holes are clean.
      Fig 2: Cleaning Piston Ring Grooves
      G03885021Courtesy of FORD MOTOR CO.