FS-2014-03

Number:__FS-2014-03
Date:__November 25, 2014
Model: All CNG or BAE Equipped Buses
Approved:
Robert L. Birdwell, Executive Director
Quality Control & Field Service
Subject:
Bolt Replacement On Front Air Bags
We have found that CNG buses and BAE Hybrid buses with drum brakes will need to have the
bottom center bolt replaced on the front air bags.
FIELD
SERVICE
BULLETIN
The bolt installed on each of the four front air bags is a ½" - 13 X 3-3/4" Grade 8 bolt. The
proper bolt is ½" - 13 X 4" Grade 8 bolt.
We will be sending you the correct bolts for each of your affected buses.
After replacing the bolt, please torque the bolt to 25-30 ft/lbs.
If you require front air bags, please contact Johnny in Field Service with the VIN and mileage
of the bus(es) needing air bags.
Installation Diagram 10-67889-000 is attached.
Make sure you follow proper safety procedures when replacing suspension bolts and air bags.
RLB:rlb
Gillig, LLC
25800 Clawiter Road
Hayward, CA 94545
(800) 735-1500
(510) 785-1500
[email protected]
Air Bag Replacement Procedure
1. To provide access to the air bag bolts, place bus on lift or over pit.
2. Fully kneel front suspension so all air pressure in the front air bags is
exhausted.
3. Drain accessory air tank, leave drain valve open.
4. Turn off main run control, verify air bags remain deflated.
5. One air bag at a time, remove the 1/2-13 bolt holding on the air bag.
Remove the bolt, flat washer and lock washer.
6. Install new flat washer, lock washer and new 1/2-13 4.0" long bolt. Start
bolt by hand and ensure bolt threads are properly engaged with threads in
the air bag.
7. Torque 1/2-13 bolt to 25–30 ft-lbs.
8. If the air bag or bolt threads strip out or the bolt cannot be torqued to
25–30 ft-lbs, the threads in the air bag are damaged and the air bag must
be replaced. Replace the air bag and re install the 1/2-13 bolt at
25–30 ft-lbs.
9. Continue to-replace the 1/2-13 bolts on all four front air bags.
10. Once all the air bags bolts are replaced, close the accessory tank drain
valve and start the engine to rebuild the air pressure. Let the front
suspension bags inflate, and check for any air bag rubbing. Correct if
found.
11. Bus can be returned to service.
If you require front air bags, please contact Johnny in Field Service with the VIN
and mileage of the bus(es) needing air bags.
Parts Required
Qty/Bus
Part Number
4
54-11325-015
4
54-12602-013
4
54-12601-010
Description
Bolt 1/2-13 4.0" Long Grade 8
1/2" Lock washer
1/2" Flat washer
10-67889-000_1.DWG ()
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