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 below project to the outside of the engine.

Fig 1: 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 With Hammer
Courtesy 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.
Fig 3: Precautions For Cracks In Cylinder Block And Cylinder Head
Courtesy of MAZDA MOTORS CORP.
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.
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.
Install new O-rings to the engine front cover.

Fig 4: Engine Front Cover And O-Rings
Courtesy of MAZDA MOTORS CORP.
NOTE:
- Install the O-rings so that the tabs of the O-rings recede into the notches.
Apply silicone sealant (TB1217D or equivalent) to the engine front cover as shown in the figure below.

Fig 5: Checking Silicone Sealant Applying Bead Thickness On Engine Front Cover
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}
CAUTION:
- Apply the silicone sealant so that it goes into the cylinder head gasket.
Apply silicone sealant (TB1217D or equivalent) to the areas shown in the figure below.

Fig 6: Applying Silicone Sealant (TB1217D Or Equivalent) To Areas
Courtesy of MAZDA MOTORS CORP.
Install the engine front cover to the engine.
NOTE:
- Temporarily install an appropriate bolt to the drive belt auto tensioner installation bole 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 7: 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 below.

Fig 8: 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}
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.
Tighten the engine front cover stud bolts.

Fig 9: Engine Front Cover Stud Bolts
Courtesy of MAZDA MOTORS CORP.

Tightening torque

7-13 N.m {72-132 kgf.cm, 62-115 in.lbf}
install the wiring harness bracket shown in the figure below.

Fig 10: Wiring Harness Bracket, Engine Front Cover And Bolts
Courtesy of MAZDA MOTORS CORP.

Tightening torque

8-11 N.m {82-112 kgf.cm, 71-97 in.lbf}
Install the wiring harness clip shown in the figure below.

Fig 11: Wiring Harness Clip, Wiring Harness Bracket And Engine Front Cover
Courtesy of MAZDA MOTORS CORP.
Install the insulator shown in the figure below.

Fig 12: Insulator And Nut
Courtesy of MAZDA MOTORS CORP.

Tightening torque

8-11 N.m {82-112 kgf.cm, 71-97 in.lbf}
Connect the A/F sensor connector and clip shown in the figure below.

Fig 13: A/F Sensor Connector And Clip
Courtesy of MAZDA MOTORS CORP.
Install the cooler hose (LO).

Fig 14: Cooler Hose (LO)
Courtesy of MAZDA MOTORS CORP.

Tightening torque

8-10 N.m {82-101 kgf.cm, 71-88 in.lbf}