Doosan DE12T - Cylinder Head Bolts; Tightening Order of Bolts by Steps

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Check the inside of combustion chamber for foreign substances, and carefully mount the
cylinder head assembly in the block by aligning the dowel pin with the dowel pin hole. Be
careful not to damage the head gasket. If the dowel pin is not in alignment, lift the cylinder
head again and then remount it.
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Coat the head bolts with engine oil, then tighten them in proper sequence to the specified
torque.
<Cylinder Head Bolts>
However, before tightening bolts, align the side face of 2 cylinder heads with parallel. They
should be adjusted in a straight line exactly.
<Tightening order of bolts by steps>
(1) First stage: Coat the bolts with engine
oil.
(2) Second stage : Tighten 1 ~ 2 threads
with hands.
(3) Third stage : Tighten at about 6 kg.m
with a wrench.
(4) Fourth stage : Tighten at rotating
angle method 90
û with a
wrench.
(5) Fifth stage : Tighten at rotating angle
method 90
û with a wrench.
(6) Sixth stage : Finally, tighten at rotating
angle method 90
û with a
torque wrench .
Especially, all bolts are tightened simulta-
neously in each step according to above
process as possible.
- 103 -
Type 1 Type 2 Type 3(12.9T) Type 4(12.9T) Type 5(10.9T)
Type
M14x1.5x153 M14x1.5x150 M14x1.5x153 M14x1.5x150 M14x1.5x150
Tighten
1st : 6kg.m 1st : 6kg.m
1st : 7kg.m
1st : 6kg.m
torque
24.5 kg.m 2nd : 180¡
2nd : 90 ¡ + 90 ¡
2nd : 90 ¡ + 90 ¡
2nd : 90 ¡ + 90 ¡
Finished : 150¡ Finished : 30¡ Finished : 90¡
TY
12.9T
TY
10.9T
TY
DL08
EAMD102I
12
32
14
89
56710
11
13
14
EAMD103I