Engine Front Cover Installation Note

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.

Fig 1: Identifying Engine Outside Positioning Pins

Courtesy of MAZDA MOTORS CORP.

If the engine front cover is newly replaced, tap the positioning pins in the two locations to the seal surface side.

Fig 2: Tapping Positioning Pins
Courtesy of MAZDA MOTORS CORP.
When reusing an engine front cover installation bolts, remove silicone sealant adhering to the bolts.
CAUTION:
- If a bolt with silicone sealant adhering to it is used, it could result in cracks in the cylinder head and cylinder block.
Fig 3: Removing Silicone Sealant Adhering To Bolts
Courtesy of MAZDA MOTORS CORP.
Completely clean and remove oil, dirt, silicone sealant or other foreign matter that may be adhering to the engine front cover, cylinder head, and cylinder block.
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.
- Apply the silicon 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.
Apply silicone sealant (TB1217D or equivalent) to the engine front cover as shown in the figure.

Fig 4: Identifying Engine Front Cover Bead Thickness Dimensions
Courtesy of MAZDA MOTORS CORP.

Bead thickness
- A: 2-6 mm {0.1-0.2 in}
- B: 4-6 mm {0.16-0.23 in}
- C: 4-8 mm {0.2-0.3 in}
Apply silicone sealant to the areas shown in the figure.

Fig 5: Identifying Cylinder Head Sealant Applying Areas
Courtesy of MAZDA MOTORS CORP.
CAUTION:
- Apply the silicone sealant so that it goes into the cylinder head gasket.
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.
Fig 6: Identifying Drive Belt Auto Tensioner Installation Bolt Hole
Courtesy of MAZDA MOTORS CORP.
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.
Tighten the engine front cover installation bolts in the order shown in the figure.

Fig 7: Engine Front Cover Installation Bolts Tightening Sequence
Courtesy of MAZDA MOTORS CORP.

Tightening torque
- 20-26 N.m {2.1-2.6 kgf.m, 15-19 ft.lbf}
Remove the bolt installed to the drive belt auto tensioner installation bolt hole when installing the drive belt auto tensioner.
Install the wiring harness bracket shown in the figure.

Fig 8: Identifying Wiring Harness Bracket Bolts With Torque Specifications
Courtesy of MAZDA MOTORS CORP.