Engine Front Cover Installation Note

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: Locating Positioning Pin With Engine Front Cover

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 At Seal Surface Side
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 Head And Cylinder Block
Courtesy of MAZDA MOTORS CORP.
When reusing an 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 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 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 below.

Fig 4: Applying Silicone Sealant To 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 5: Applying Silicone Sealant Between Cylinder Head And Cylinder Block
Courtesy of MAZDA MOTORS CORP.
CAUTION:
- Do not apply engine coolant to the O-ring (1). Otherwise, the O-ring could swell causing a seal malfunction.
  
  Fig 6: Identifying O-Rings With Engine Front Cover
  Courtesy of MAZDA MOTORS CORP.
- Do not apply oil (such as engine oil, ATF) to the O-ring (2). Otherwise, the O-ring could swell causing a seal malfunction.
Install a new O-ring to the O-ring installation groove of the engine front cover.
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 7: 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 3 bolt of the tightening order, install the bolt with new washer.
Tighten the engine front cover installation bolts in the order shown in the figure below.

Fig 8: 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.

Return the engine wiring harness to its original position using the following procedure.

Connect or install the following parts.

Step 1

Fig 9: Engine Wiring Harness Components With Torque Specification (Step 1)

Courtesy of MAZDA MOTORS CORP.

COMPONENT DESCRIPTION

1	Bolt
2	Wiring harness clip
3	Wiring harness clip
4	Crankshaft position (CKP) sensor connector
5	Engine oil solenoid valve connector
6	A/F sensor connector
7	Oil pressure switch connector

Step 2

Fig 10: Engine Wiring Harness Components With Torque Specification (Step 2)

Courtesy of MAZDA MOTORS CORP.

COMPONENT DESCRIPTION

1	Wiring harness clip
2	Wiring harness clip
3	Wiring harness protector installation nut

Install the throttle body. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION ).

Connect or install the following parts.

Fig 11: Intake-Air System Components With Torque Specification

Courtesy of MAZDA MOTORS CORP.

COMPONENT DESCRIPTION

1	High pressure fuel pump connector
2	Exhaust camshaft position sensor connector
3	Intake camshaft position sensor connector
4	Wiring harness clip
5	Bolt

Connect the purge solenoid valve connector. (See PURGE SOLENOID VALVE REMOVAL/INSTALLATION ).