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Home >> Mazda >> 2021 >> 3 Base >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 22 (Engine Mechanical System (VIN M)) >> Timing Chain Removal/Installation >> Engine Front Cover Installation Note
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Engine Front Cover Installation Note

WARNING: This page is about a different variant/trim than selected.
NOTE:
  • For a new engine front cover, the positioning pins in the two locations shown in the figure project to the outside of the engine.
G13107937Courtesy of MAZDA MOTORS CORP.
  1. If the engine front cover is newly replaced, tap the positioning pins in the two locations to the seal surface side.
    G11436850Courtesy of MAZDA MOTORS CORP.
    CAUTION:
    • If a bolt with silicone sealant adhering to it is used, it could result in cracks in the cylinder head and cylinder block.
    G13556911Courtesy of MAZDA MOTORS CORP.
  2. When reusing the engine front cover installation bolts, remove silicone sealant adhering to the bolts.
    CAUTION:
    • If oil, dirt and silicone sealant remains on the silicone sealant application area, the silicone sealant will not seal which will cause oil leakage.
  3. Completely clean and remove any oil, dirt, silicone sealant or other foreign matter that may be adhering to the engine front cover, cylinder head, and cylinder block.
    CAUTION:
    • Apply the silicone sealant in a single, unbroken line.
    • To prevent silicone sealant from hardening, adhere the engine front cover and the cylinder block firmly within 10 min. after applying silicone sealant. After adhering them, tighten the installation bolts immediately.
  4. Install new O-rings to the engine front cover.
    G13556912Courtesy of MAZDA MOTORS CORP.
    NOTE:
    • Install the O-rings so that the tabs of the O-rings recede into the notches.
  5. Apply silicone sealant (TB1217D or equivalent) to the engine front cover as shown in the figure.
    G12188722Courtesy of MAZDA MOTORS CORP.

    Bead thickness 

    1. 2-6 mm {0.1-0.2 in}
    2. 4-6 mm {0.16-0.23 in}
    3. 4-8 mm {0.2-0.3 in}
    CAUTION:
    • Apply the silicone sealant so that it goes into the cylinder head gasket.
  6. Apply silicone sealant (TB1217D or equivalent) to the areas shown in the figure.
    G13174720Courtesy of MAZDA MOTORS CORP.
  7. Install the engine front cover to the engine.
    NOTE:
    • Temporarily install an appropriate bolt to the drive belt auto tensioner installation bolt hole to prevent:
    • A silicone sealant adhesion malfunction in the drive belt auto tensioner installation bolt hole.
    • A bolt mis-installation due to silicone sealant hardening.
    G12188724Courtesy of MAZDA MOTORS CORP.
  8. Prepare an appropriate M8 x 1.25 bolt (length 40 mm {1.6 in}).
    CAUTION:
    • For the number 10 bolt of the tightening order, install the bolts with new washer.
  9. Tighten the engine front cover installation bolts in the order shown in the figure.
    Fig 1: Engine Front Cover Bolts Tightening Sequence
    G13174722Courtesy of MAZDA MOTORS CORP.
    NOTE:
    • Install stud bolts because there are no stud bolts installed on a new engine front cover.
    • If the engine front cover is reused, tighten the stud bolts because they may have loosened.
  10. Tighten the engine front cover stud bolts.
    Fig 2: Engine Front Cover Stud Bolts With Torque Specification
    G13556917Courtesy of MAZDA MOTORS CORP.
  11. Install the wiring harness bracket shown in the figure.
    Fig 3: Wiring Harness Bracket Bolts With Torque Specification
    G13556884Courtesy of MAZDA MOTORS CORP.
  12. Install the wiring harness clip shown in the figure.
    G13107947Courtesy of MAZDA MOTORS CORP.
  13. Install the insulator shown in the figure.
    Fig 4: Insulator Nut With Torque Specification
    G13556882Courtesy of MAZDA MOTORS CORP.
  14. Connect the A/F sensor connector and clip shown in the figure.
G12188684Courtesy of MAZDA MOTORS CORP.
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