Engine - Revised Cylinder Head Bolts/Service Procedure
NUMBER: 02-111-10DATE: 08/02/10
APPLICABILITY:
2010 MY Forester 2.5L NA
2010MY and later, Forester Turbo
2010MY and later, Impreza 2.5L NA
2010MY and later, WRX, STI Turbo
SUBJECT:
Cylinder Head Bolts
INTRODUCTION
The purpose of this bulletin is to inform you that the surface treatment of the cylinder head bolts has changed for production purposes along with the installation procedure.
COUNTERMEASURE IN PRODUCTION
The new style bolts were used in production on December 4, 2009.
PART INFORMATION
NOTE:
The bolts are interchangeable and can be mixed, however the new procedure must be followed regardless.
SERVICE PROCEDURE/INFORMATION
SOHC Cylinder Head Bolt Installation
1) Clean the bolt threads and the bolt holes in the cylinder block.
CAUTION:
To avoid erroneous tightening of the bolts, clean out the bolt holes sufficiently by blowing with compressed air to eliminate engine coolant etc.
2) Apply a sufficient coat of engine oil to the washer and bolt thread.
3) Tighten all bolts to 40 N.m (4.1 kgf-m, 29.5 ft-lb) in alphabetical order (refer to illustration).
4) Tighten all bolts to 95 N.m (9.7 kgf-m, 70.1 ft-lb) in alphabetical order.
CAUTION:
If the bolt makes stick-slip noise (squeaking sound) during tightening, start over from step (1). In this case, the cylinder head gasket can be reused.
5) Loosen all the bolts by 180° in the reverse order of installing, and loosen them further by 180°.
6) Tighten all bolts to 10 N.m (1.0 kgf-m, 7.4 ft-lb) in alphabetical order.
7) Tighten all bolts to 30 N.m (3.1 kgf-m. 22.1 ft-lb) in alphabetical order.
8) Tighten all bolts to 60 N.m (6.1 kgf-m. 44.2 ft-lb) in alphabetical order.
9) Tighten all bolts by 80° - 90° in alphabetical order.
10) Tighten all bolts by 40° - 45° in alphabetical order. Caution: Do not exceed 45°
11) Tighten bolts (a) and (b) further by 40° - 45°
Caution: Do not exceed 4°
CAUTION:
Make sure the total "tightening angle" of steps (10) and (11) does not exceed a total of 90°.
DOHC Cylinder Head Bolt Installation
1) Clean the bolt threads and the bolt holes in the cylinder block.
CAUTION:
To avoid erroneous tightening of the bolts, clean out the bolt holes sufficiently by blowing with compressed air to eliminate engine coolant etc.
2) Apply a sufficient coat of engine oil to the washer and bolt thread.
3) Tighten all bolts to 40 N.m (4.1 kgf-m, 29.5 ft-lb) in alphabetical order (refer to illustration).
4) Tighten all bolts to 95 N.m (9.7 kgf-m, 70.1 ft-lb) in alphabetical order.
CAUTION:
If the bolt makes stick-slip noise (squeaking sound) during tightening, start over from step (1). In this case, the cylinder head gasket can be reused.
5) Loosen all the bolts by 180° in the reverse order of installing, and loosen them further by 180°.
6) Tighten all bolts to 10 N.m (1.0 kgf-m, 7.4 ft-lb) in alphabetical order.
7) Tighten all bolts to 30 N.m (3.1 kgf-m, 22.1 ft-lb) in alphabetical order.
8) Tighten all bolts to 70 N.m (7.1 kgf-m, 51.6 ft-lb) in alphabetical order.
9) Tighten all bolts by 80° - 90° in alphabetical order.
10) Tighten all bolts by 40° - 45° in alphabetical order.
Caution: Do not exceed 45°
11) Tighten bolts (A) and (B) further by 40° - 45°
Caution: Do not exceed 45°
CAUTION:
Make sure the total "tightening angle" of steps (10) and (11) does not exceed 90°.
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