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

11-2-2020
800 Volt Rear Coolant Hose Retrofit
Service Specified Buses
Next Service Opportunity
SC-20-155
CC45Z

NOTICE! It is expected that this process will require 2 hours per bus. Please
schedule appropriately to minimize vehicle downtime.

800 VOLT REAR COOLANT HOSE RETROFIT
Retrofit Description:

This updates the rear coolant hose from a flexible hose to a formed hosed for improved reliability.

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:
•
•
•
•

Side Cutting Pliers
Catch Pan
Flat Blade Screwdriver
50-50 Ethelene Glycol Coolant (Obtain Locally) 7 Gallons

Kit Parts Required:
• 055917
KIT, COOLANT HOSE, DCDC TO VFD (Consisting of)
o 048059
HOSE, MOLDED
o 044137
CLAMP, CONSTANT TENSION WORM DRIVE
o 012138
CABLE TIE, HEAVY DUTY .5WIDE 9.1" BLACK
o 020657
CABLE TIE .18 X 12""
o 045827
INSULATION SLEEVE, PIPE WRAP ,1.5", AUX HEAT

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

1 EA
2 EA
2 EA
3 EA
7 IN

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Procedure:
1. Complete the Proterra approved Lockout/Tagout procedure to make the bus safe for work.
2. Using a Catch Pan, drain the power electronics coolant loop so that the rear coolant hose
may be removed for replacement.

Hose

Drain Plug

3. Using Side Cutting Pliers, remove the two cable ties that secure the hose.

Cable
Ties

4. Using a Flat Blade Screwdriver, remove the Hose Clamps and the Hose from the bus.

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. Wrap the Molded Hose (048059) with Pipe Wrap (045827).
6. Using a Flat Blade Screwdriver, install the Hose (048059) and Pipe Wrap (045827) in place of
the original hose using the Hose Clamps that were removed earlier. Using Cable Ties
(020657), secure the Pipe Wrap to the Hose.
Note: The Streetside section of the hose must be vertical.

012138

020657
Swivel
Spacer

020657
Vertical
Section

7. Using Electrical Tape, wrap the steel tube even with the Streetside end of the Lenze. Using
Cable Ties (012138), secure the Cable Tie Mount and Swivel Spacer to the Hose and steel
tube on the electrical tape as shown in the previous photograph. Secure the Hose to the steel
tube with a Cable Tie leaving a small gap between the Hose and steel tube.

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. The following photographs show top and Curbside views of the completed Hose (048059)
installation.
Note: Do not overtighten the Cable Tie (020657) shown in the second photograph. Leave a
gap of approximately 5mm between the Hose and steel tube.

Gap

9. Remove the Lockout/Tagout devices.
10. Refill the Power Electronics Coolant Loop using the fill port at the rear of the bus.

11. Remove the Lockout/Tagout devices and return the bus to service after verifying that there
are no coolant leaks.

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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