ISSUE DATE:
SERVICE BULLETIN SUBJECT:
VINs or MODELS AFFECTED:
COMPLETE BY:
SERVICE BULLETIN #:
Labor Operation Code:

2-10-2021
40 Foot 800 Volt Parking Brake Release Retrofit
Service Specified Buses
Next Service Opportunity
SC-21-21
BD42Z

NOTICE! It is expected that this process will require 3 hours per bus. Please
schedule appropriately to minimize vehicle downtime.

40 FOOT 800 VOLT PARKING BRAKE RELEASE RETROFIT
Retrofit Description:

This procedure updates the parking brake air tank from a half-gallon to a two and one-half gallon tank
for improved performance.

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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Tools/Parts Required
Tools and Supplies Required:
•
•
•
•
•
•
•
•
•

Ratchet
13mm Socket
13mm Combination Wrench
Standard Combination Wrench Set
Calibrated Torque Wrench
Orange Torque Stripe Paint
Side Cutting Pliers
Approved Lifting Devices for the Bus
Loctite 567

Parts Required:
•

055961
KIT, PNEUMATIC COMPONENTS, 2 1/2 GALLON TANK 40FT (Consisting of)
• 000321
VALVE, SINGLE CHECK, SC-3
1 EA
• 000624
TUBING, AIR BRAKE, BROWN, 3/8 OD"
120 IN
• 006722
FITTING, COMPOSITE, 90 DEG, SWIVEL, 1/2 MPT"X 3/8 TUBE" 2 EA
• 111-5683
VALVE, DRAIN, AIR TANK
1 EA
• 042547
CABLE TIE, EDGE CLIP, FRONT EDGE, 8"
2 EA
• 052278
TANK, AIR, 2.5GAL
1 EA
• 006487
FITTING, MALE ELBOW, 1/2 NPT
1 EA
• 001146
FITTING, PTC, COMPOSITE, UNION, 3/8 OD TUBE"
1 EA
• 003784
PIPE BUSHING, BRASS, 1/2 X ¼
1 EA
• 000640
FITTING, BRASS, BUSHING, 3/8 MPT 1/4" FPT
1 EA
• 001161
FITTING, BRASS, PLUG, SOCKET HEAD, 1/2 PT"
1 EA
• 005443-004 BOLT,HEX,FLANGE,STL,YZPL,CLASS 10.9, M8-1.25X25X25
4 EA
• 013575
LKNT,HEX,FLANGE,STL,1000HSS,CLASS 10, M8-1.25
4 EA

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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Procedure:
1. Complete the Proterra approved Lockout/Tagout procedure to make the bus safe for work.
2. This procedure is best accomplished with the bus lifted for better access to the Prodrive area
of the bus.
3. This procedure will remove the 1/2 Gallon Air Tank at the curbside rear of the bus as shown in
the following illustration.

4. The procedure will replace the removed tank with a new 2.5 Gallon Air Tank as shown in the
following illustration.

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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5. Working on the Streetside Rear of the bus, open the curbside hatch and open the three air
valves shown in the following photograph to drain the air tanks.

6. Using a Schrader Valve Tool, remove the four valve cores shown to drain the air bags.

7. Disconnect the air lines from the push-on fittings on the original Air Tank as shown in the
following illustration.

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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8. Using a 13mm Ratchet/Socket, remove the two M8 Bolts that secure the Air Tank to the
Prodrive frame. Remove the Air Tank. It will not be reused.

9. Using the parts from the kit, install the fittings shown in the following illustration onto the new
Tank (052278). Apply a small amount of Loctite 567 to the tapered threads on the fittings
before installing them onto the Tank. All fittings must be torqued two to three full turns past
finger tight.

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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10. Using the following illustration as a guide, mark the four locations shown for drilling using a
Permanent Marker.

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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11. Using a Power Drill with a 10mm Drill Bit, drill a hole in each of the four marked locations for
mounting the new Tank (052278).
12. Using a 13mm Ratchet/Socket and a 13mm Combination Wrench, install the new Tank
(052278) using four M8 Bolts (005443-004) and four M8 Locknuts (013575) from the kit.

13. Using a Calibrated Torque Wrench with a 13mm Socket, torque the fasteners to 29 foot
pounds.
14. Using Orange Torque Stripe Paint, mark the properly torqued fasteners

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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15. Connect the air lines to the new Tank (052278) as shown in the following illustration.

16. The following illustration shows the connection to the Check Valve on the new Tank (052278).

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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17. A Union (001146) and additional Tubing (000624) are supplied in case the installed Tubing
needs extending.

18. Using Cable Ties (042547), secure the air lines to the Prodrive Frame.
19. Using a Schrader Valve Tool, replace the valve cores that were removed earlier.

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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20. Close the valves that were opened earlier to drain the air system.

21. Lower the bus if it was raised to complete the retrofit.
22. Remove the Lockout/Tagout devices and power on the bus.
23. Allow the bus to build air pressure until the compressor stops.
24. Verify that there are no air leaks. Repair any leaks that exist.
25. Return the bus to service.

Headquarters: 1815 Rollins Road, Burlingame, CA 94010
East Coast Manufacturing: 1 Whitlee Court, Greenville, SC 29607
West Coast Manufacturing: 383 Cheryl Lane, City of Industry, CA 91789

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