Installing The Cylinder Head Assembly - Yanmar 6LY3 series Service Manual

ENGINE
Installing the Cylinder Head
Assembly
NOTICE: Ensure that the mating surfaces of the
cylinder head and the engine block are absolutely
clean of all dirt and any oil film. Inspect each
cylinder bore and remove any debris, lint and / or
shavings of any kind.
1. Measure the flatness of the cylinder head and
the engine block to ensure dimensions are
within the specified values. See Inspecting the
Cylinder Head on page 5-28.
2. Set a new, clean and dry head gasket
(Figure 5-103, (1)) on the engine block using
the pilot pins to guide gasket position.
Figure 5-103
Figure 5-103
1 – Head Gasket
3. Set the preassembled cylinder head gently on
top of the head gasket using the pilot pins to
position the cylinder head.
4. Oil the threads and flanges of each head bolt.
5. Set (do not drop) 13 M14 x 139 mm head bolts
into the holes on the operation side
(Figure 5-104, (2)) of the engine
(Figure 5-104).
5-64
(1)
0005805
© 2007 Yanmar Marine International
Assembling the Engine and Components
Figure 5-104
20 12
26 18 10
(3)
1 2
24 16 8
22 14
Figure 5-104
1 – Coolant Pump End
2 – Operation Side
3 – Flywheel End
4 – Non-Operation Side
6. Set (do not drop) 13 M14 x 149 mm head bolts
into the holes on the non-operation side
(Figure 5-104, (4)) of the engine
(Figure 5-104).
7. Finger tighten all of the head bolts.
8. Tighten the head bolts in the sequence shown
in Figure 5-104 in three stages. NOTICE: Use
the values for the new bolts or the used bolts.
9. Tighten all the head bolts to the specified
torque value shown in the 1
following table. Use the proper torque sequence
as shown in Figure 5-104.
Cylinder Head Bolt Torque
st
1 Stage
Used 108 N·m
Head (11 kgf·m)
Bolts (79.6 lb-ft)
118 N·m
New Head
(12.0 kgf·m)
Bolts
(87 lb-ft)
10. Repeat this tightening sequence and bring all
the head bolts to the torque value given in the
2 nd stage.
11. Repeat the tightening sequence and bring all
the head bolts to the torque value given in the
rd
3 stage. NOTICE: Head identification No. is
marked on the upper surface on the flywheel
end.
6LY3 Service Manual
(4)
3 5 13 21
1 7 15 23
(1)
3 4 5 6
2 9 17 25
6 4 11 19
(2)
0005806
st
stage of the
nd rd
2 Stage 3 Stage
167 N·m 206 ± 10 N·m
(17 kgf·m) (21 ± 10 kgf·m)
(123.1 lb-ft) (144.5 lb-ft)
177 N·m 226 ± 10 N·m
(18.0 kgf·m) (23 ± 1 kgf·m)
(130.5 lb-ft) (159.3 lb-ft)