ISSUE DATE:
SERVICE BULLETIN SUBJECT:
VINs or MODELS AFFECTED:
COMPLETE BY:
SERVICE BULLETIN #:
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10/26/2021
Forty Foot Compressor Snorkel Intake Retrofit
Service Specified Buses
Next Service Opportunity
SC-21-151
N/A

NOTICE! It is expected that this process may require up to 1 hour per bus. Please
schedule appropriately to minimize vehicle downtime.

FORTY FOOT COMPRESSOR SNOKEL INTAKE RETROFIT
Description

The procedure adds a snorkel to the input of the air compressor to reduce contamination of the
compressor.

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
10mm Socket
10mm Combination Wrench
Phillips Screwdriver
Side Cutting Pliers

Kit Parts Required:
•

059515
RETROFIT KIT, AIR COMPRESSOR INTAKE (Consisting of)
• 054841
KIT, AIR FILTER HOUSING RELOCATION TUBE
1 EA
• 012138
CABLE TIE, HEAVY DUTY .5WIDE 9.1" BLACK
6 EA
• 012108
SWIVEL BUNDLE, SPACER
3 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 will remove the Compressor Air Intake shown in the first illustration and extend
it with a Snorkel as shown in the second illustration.

3.

This procedure shows all steps for installing the Snorkel on a 40-foot bus with Aux Heat. This
represents the most complex installation. Some steps may be omitted if the Compressor Air
Intake is more easily accessible than it is on the bus with Aux Heat shown in this procedure.

4.

Open the Trunk Hatch and the Curbside Rear hatch to access the Air Compressor.

5.

Inspect the bus to determine if the Air Compressor Intake Worm Drive Clamp can be loosened
with the Compressor Air Filter Assembly installed.

Intake
Clamp

6.

If the Intake Worm Drive Clamp is accessible, proceed to step 14. Otherwise proceed to step 7
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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7.

Using a 10mm Ratchet/Socket and a 10mm Combination Wrench, remove the bolt shown in
the following photograph.

Bolt
Clamp

8.

Using a Flat Blade Screwdriver, loosen the Worm Drive Clamp shown in the Previous
Photograph.

9.

Remove the Filter Assembly from the bus.

Air Intake

10.

Using an 8mm Ratchet/Socket, remove the Compressor Air Intake.

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.

Place the large end of the Hose inside the intake as shown in the following photograph.

12.

Using a #2 Phillips Screwdriver, Secure the Intake to the Hose with a Worm Drive Clamp from
the kit.

13.

Using a Flat Blade Screwdriver and 10mm Wrenches, reinstall the Filter Assembly onto the Air
Compressor without the Intake.

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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14.

Test fit the Snorkel and Hose to find the best location for mounting them. The mounting
location should be as high as possible without interfering with any other components.

15.

Using a #2 Phillips Screwdriver, connect the Hose to the Compressor Filter Assembly using a
Worm Drive Clamp from the Kit.

Clamp

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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16.

Using Cable Ties (012138) and Swivel Spacers (012108), secure the hose along its route.

17.

Using Side Cutting Pliers, trim the ends of the Cable Ties (012138).

18.

Close the Side Panel and the Trunk.

19.

Remove the Lockout/Tagout devices and 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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