4/23/2021

SS 700-WST2021 49X Vertical Exhaust Loose - DTNA Solutions

DTNA Solutions  Service Solutions  Western Star

 SS 700-WST2021 49X Vertical Exhaust Loose

SS 700-WST2021 49X Vertical Exhaust Loose 
Applicable Vehicles
WST 49X vehicles built with dual/split vertical exhaust

Symptoms
Loose exhaust, audible noise, excessive movement of grab handles at the lower B-pillar mounting.

Issue
Torqueing sequence of exhaust pipe mounting brackets and fasteners.

Solution
Re-torque fasteners to correct specs per attached procedure document.
Labels :
49X

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4/23/2021

SS 700-WST2021 49X Vertical Exhaust Loose - DTNA Solutions

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FRACAS - 13595 - 49X Dual/Split Vertical Exhaust Loose at Lower B-Pillars
Proposed Draft Production and Field service Containment proposal:
Critical that assembly is confirmed for correct torques and Key dimensions D/E Noted Below

D

E

Front View
Lower Clamp

49X B-Pillar Exhaust
Lower Clamp-to-Casting Spacing Control
1. Remove exhaust shield
2. Loosen lower clamp to allow some rotational play in joint
3. Insert 12.5mm thick spacer block to set lower clamp-to-casting
FWD spacing.

4. Torque bottom isolator fastener to 26 ft.lb.
5. Follow torque sequence below.(see next pg.)
Rear View
Lower Clamp

6. Check lower clamp-to-casting REAR spacing.(min. 10 mm needed
to both Rear and Front bracket to ensure exhaust shield clearance
to cab skin)

Exhaust fastener torque sequence
5

2

4

1
3
26 FtLb
11 FtLb

Lower brackets

2/2/2021

6
Upper brackets

LOWER LH EXHAUST CAB BRACKET AND CLAMP MEASUREMENTS

NOK:
Actual: 8.5mm

OK:
Target: 12.5mm
Actual: 12mm

Gap Needs to
be Minimum of
10MM at Front
and Back to
avoid exhaust
shield contact
to cab
FORWARD MEASUREMENT
(Target 12.5mm)

AFT MEASUREMENT

FRACAS - 13595 - 49X Dual/Split Vertical Exhaust Loose at Lower B-Pillars
Proposed Production and Field service Containment proposal:

D

F

7. Confirm Minimum gap of 15 MM
between Cab Valence panel and
exhaust elbow. Maintain Max. 21
MM (or 203MM) to avoid risk of
tight service clearance to battery box
cover or other chassis mounted
components. Loosen and retorque
purple exhaust clamp(to 41 FtLBs) if
required.

8. Final Check for Vertical exhaust shields and Verification on Gaps and motion
after repair and reinstalling exhaust Shield and Grab Handle

B. Check minimum Gap found
to Shield and cab skin. It will
need to be > 4 mm .

A. Measure and Record minimum
Gap found- Needs to be > 4 mm
or can have risk for “clicking” or
paint damage from
motion/vibrations.
C. Measure similar gap (Min. 4 mm)
to back bracket to exhaust shield
D. Apply force to grab handle.
Deflection(shield should return to
original loc) is not to exceed
+ - 3MM or assembly torques will
need reconfirmed and retightened.

Offline Repair/ validation steps

1. Remove LH or RH exhaust Shield in offline or Service bay.
2. Reinstall grab handle (to allow for force testing in step 11 &12 below.)
3. Mark with Paint pen the 5 joints and observe motions for looseness.
4. Review where Looseness Is occurring? Upper or lower isolators or brackets?
5. Review Height of cab line mark from the Pipe to the lower orange bracket if marked and if it has moved
6. Check , record and adjust Height of 48+- 3mm clamp from Page 1 (sheet 6/24) if necessary
7. Check, record and adjust height of 98 +- 3mm to top clamp from Page 1(sheet 5/24)
8. Reset Lower clamp to exhaust clamp position per PPT page 2
9. Retorque all joints per SEQUENCE to PPT slide 3.
10. Confirm clamp spacing is minimum of 10MM per PPT slide 4( on both the front and back)
11. Confirm Deflection to bracket is less than +- 3mm Per PPT slide 6 step D
12. Confirm exhaust elbow Height is ok per PPT Page 5 step 7
13. Confirm if No paint damage to cab. If so, touchup as required.
14. If Ok, Reassemble exhaust shield and complete PPT slide 6 for confirmation and close cry.
15. APA/QA team Complete 43N Vertical exhaust check sheet before release of Unit.