exhaust flow modification hd785 - hd985
TRANSCRIPT
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
1/11
Page 1 of 11Service News
W2M2005D0031
Applicable vehicles
HD785-5: #4001 and after
HD985-5: #1021 and after
Modification procedure manual for the exhaust flow route changeover
system on HD785-5/HD985-5
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
2/11
Page 2 of 11Service News
1. Details of the modification
Current part Improved part
Outline of the modification is as follows.
The inner diameterA of the exhaust outlet tube from the exhaust flow route changeover
box and the inner diameterB of the exhaust inlet tube into the body are increased in order
to reduce the exhaust resistance.
For the above purpose, the exhaust flow route changeover box and the exhaust inlet tube
into the body are replaced.
153.8
For use with the HD785-5 dump trucks equipped with the exhaust flow route changeover
system, the improved parts for the system which are effective to reduce the exhaust
resistance, and therefore, implement the modification to improve the system referring to this
modification procedure manual.
155.2
202
204.7
Inner diameter of the exhaust outlet
tube from the exhaust changeover box
Inner diameter of the exhaust inlet tube
into the body
A
B
Fig. 1
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
3/11
Page 3 of 11Service News
HD785-5
561-84-64700 BOX
01010-81230 BOLT Consumable parts
01643-31232 WASHER Consumable parts
561-84-64820 TUBE
561-84-64830 PLATE
561-02-61240 V-CLAMP Consumable parts
568-95-11160 BAND Consumable parts
01580-11210 NUT Consumable parts
01643-31232 WASHER Consumable parts
561-84-64240 BAND Consumable parts
01010-81030 BOLT Consumable parts
01580-11008 NUT Consumable parts
01643-31032 WASHER Consumable parts
HD985-5
561-84-64700 BOX
01010-81230 BOLT Consumable parts01643-31232 WASHER Consumable parts
561-84-6D151 TUBE
561-84-64830 PLATE
561-02-61240 V-CLAMP Consumable parts
568-95-11160 BAND Consumable parts
01580-11210 NUT Consumable parts
01643-31232 WASHER Consumable parts
561-84-64240 BAND Consumable parts
01010-81030 BOLT Consumable parts01580-11008 NUT Consumable parts
01643-31032 WASHER Consumable parts
3. Installation procedure
3.1 Preparations
Park the vehicle on a flat place. Stop the engine, turn on the parking brake and apply chocks to the tires.
2. Table of necessary parts for modification of the exhaust flow route
changeover system
No.
1
Part No. Part name Q'ty Remarks
1
2
3
4
5
6
7
8
9
10
11
12
1
1
6
6
1
1
1
2
1
2
2
1
Remarks
1 1
No. Part No. Part name Q'ty
13
2 63 6
4 1
5 1
6 2
7 1
8 2
9 2
10 1
11 1
Numbers indicated after the part numbers in the descriptions of this manual and numbers
given in the drawings correspond to the numbers in the above table of parts.
12 1
13 1
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
4/11
Page 4 of 11Service News
3.2 Removal of the exhaust flow route changeover box and reworking of the related parts
1. Remove the exhaust flow route changeover box.
2. Rework the exhaust tube (561-84-64141).
Cut 25 mm of the top end section (hatched section).
Rework (Cut the top
end section.)
Exhaust tube
(561-84-64141)
Remove
Exhaust flow route changeover box
(561-84-64101)
Cut to remove this
section.
Fig. 2
Fig. 3
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
5/11
Page 5 of 11Service News
3. Rework the fire prevention cover (561-89-62513). (Add a notch.)
Add a notch.
Fig. 4
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
6/11
Page 6 of 11Service News
3.3 Installation of the improved exhaust flow route changeover box
Install the improved exhaust flow route changeover box 1 (561-84-64700) and fix the
exhaust tube using the clamp 6 (561-02-61240), band 7 (568-95-11160) and band 10
(561-84-64240) and connect the exhaust tube to the changeover box.
Tightening torque for the exhaust flow route changeover box mounting bolts:
98 - 123 Nm {10 - 12.5 kgm}Tightening torque for the clamp 6 (561-02-61240): 6.9 - 8.3 Nm {0.7 - 0.85 kgm}
1
23
6
7
8 910
11
1213
Fig. 5
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
7/11
Page 7 of 11Service News
3.4 Reworking the body
1.
2.
3.
Remove the exhaust tube (including the plate) welded to the body. (The hatched
section in the drawing below)
Remove the hatched section around the hole for the exhaust tube to expand the size of
the hole.
Weld the exhaust inlet tube 4 (HD785-5: 561-84-64820, HD985-5: 561-84-6D151) andthe plate 5 (561-84-64830) to the body by actually positioning the parts to.
Refer to Fig. 8, 9, 10 and 11 on pages 8 thru 11.
Remove the exhaust tube
and the plate.
Fig. 6
Remove thebe
hatched section.
Fig. 7
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
8/11
Page 8 of 11Service News
Fig.
8
HD
985-5
HD
785-5
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
9/11
Page 9 of 11Service News
Fig.
9
Insertion
depth
Insertion
depth:
55
Tightening
torque
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
10/11
Page 10 of 11Service News
F
ig.
10
Tightening
torque
-
7/27/2019 Exhaust Flow Modification HD785 - HD985
11/11
Page 11 of 11Service News
3.5 Adjustment of the exhaust inlet tube position to weld
Carry out this work after the body mount adjustment work.
(1)
(2) Slip the plate (561-84-64830) on the tube (561-84-64820).
(3)
(4)
(5)
(6) Raising and lowering the body, check that the exhaust box operates properly.
Fix the dimensions "A" of the exhaust box (561-84-64700) to 65 mm using a jig (vice,
etc.).
After aligning the centers of the box and the tube at the contact surface weld the tube
and plate to the body by actually positioning the parts to the body.
(Front to back and side to side runout should be 2 mm or less.)
After the welding work, raise the body to remove the jig and check that the dimension
"A" is 120 mm.
Lower the body slowly to seat and check that the body and the flange surface of the
exhaust box comes to even contact without gap.
Fig. 11
Front to back and side
to side runout should be
2 mm or less
When the body is raised: 120
When the body is lowered: 65
The flange surface should come
to even contact without gap.