Removing The Cylinder Head

CYLINDER HEAD

EAS24120
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REMOVING THE CYLINDER HEAD                                a. Place a straightedge “1” and a thickness
1. Remove:                                                   gauge “2” across the cylinder head.
 • Cylinder head bolts
NOTE:
• Loosen the bolts in the proper sequence as
  shown.
• Loosen each bolt 1/2 of a turn at a time. After
  all of the bolts are fully loosened, remove them.

                                                          b. Measure the warpage.
                                                          c. If the limit is exceeded, resurface the cylinder
                                                             head as follows.
                                                          d. Place a 400–600 grit wet sandpaper on the
                                                             surface plate and resurface the cylinder head
                                                             using a figure-eight sanding pattern.
                                                      NOTE:
EAS24160                                                  To ensure an even surface, rotate the cylinder
CHECKING THE CYLINDER HEAD                                head several times.
1. Eliminate:
 • Combustion chamber carbon deposits                     ▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
   (with a rounded scraper)                               EAS24240

NOTE:                                                     INSTALLING THE CYLINDER HEAD
Do not use a sharp instrument to avoid damag-             1. Install:
ing or scratching:                                          • Cylinder head
• Spark plug bore threads                             NOTE:
• Valve seats                                             Pass the timing chain through the timing chain
                                                          cavity.
2. Check:
 • Cylinder head                                          2. Tighten:
   Damage/scratches → Replace.                              • Cylinder head bolts (M10) “1”–“10” New
 • Cylinder head water jacket                               • Cylinder head bolts (M6) “11”, “12”
   Mineral deposits/rust → Eliminate.                     EW3P61013

3. Measure:                                                      WARNING
 • Cylinder head warpage                                  Replace the bolts with new ones.
   Out of specification → Resurface the cylinder
   head.                                              NOTE:
                                                          Tighten the bolts using the following procedure.
           Warpage limit
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            0.10 mm (0.0039 in)
                                                          a. Lubricate the cylinder head bolts and wash-
                                                             ers with engine oil.
                                                          b. Install the washers and cylinder head bolts.
                                                          c. Tighten the cylinder head bolts (M10) in the
                                                             proper tightening sequence as shown.

                                                                          Cylinder head bolt (M10)
                                                                 T.
                                                                     R.
                                                                           1st
                                                                            25 Nm (2.5 m·kg, 18 ft·lb)

                                                          d. Loosen and retighten the cylinder head bolts
                                                             in the proper tightening sequence as shown.

                                                   5-22
                                                                        CYLINDER HEAD

             Cylinder head bolt (M10)
       T.
        R.
              2nd
               25 Nm (2.5 m·kg, 18 ft·lb)

e. Tighten the cylinder head bolts further to
   reach the specified angle 175–185° in the
   proper tightening sequence as shown.

             Cylinder head bolt (M10)
       T.     Final
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        R.

               Specified angle 175–185°
EW3P61014

       WARNING
If the bolt is tightened more than the speci-
fied angle, do not loosen the bolt and then re-
tighten it. Instead, replace the bolt with a new
one and perform the procedure again.
EC3P61033

CAUTION:
• Do not use a torque wrench to tighten the
  bolt to the specified angle.
• Tighten the bolt until it is at the specified
  angle.
NOTE:
On a hexagonal bolt, note that the angle from
one corner to another is 60°.

f. Tighten the cylinder head bolts (M6) in proper
   tightening sequence as shown.

              Cylinder head bolt (M6)
       T.
        R.
               12 Nm (1.2 m·kg, 8.7 ft·lb)

                                                    5-23