SERVICE MANUAL BULLETIN
This Service Manual Bulletin is prepared by the Publications Department of New Flyer Industries
Canada ULC. Refer to details below.

SMB-186
ISSUE DATE: Sep 20 2019

APPLICABILITY
VEHICLE LENGTH

 30ft.

 35ft.

 40ft.

 60ft.

 Xcelsior®

 MiDi®

 Invero®

 Low Floor

 High Floor

 Diesel

 Diesel/Electric

 CNG

 Fuel Cell

 Trolley/Electric

 Battery/Electric

 ALL

VEHICLE TYPE

FUEL TYPE

 ALL

 LNG
 ALL

SUBJECT

Direct Drive Scroll Air Compressor - Powerex

SECTION TITLE

PM - PREVENTIVE MAINTENANCE

DETAILS

This bulletin provides revised information for the Preventive Maintenance
on the Powerex Direct Drive air compressor.
This information supersedes any prior information on this subject
already provided in your New Flyer Service Manual.
Make this Service Bulletin available to service personnel to inform them
of changed information.

SMB-186

The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2019 New Flyer Industries Canada ULC

1 of 12

SERVICE MANUAL BULLETIN
SMB-186
1.

DIRECT DRIVE SCROLL
COMPRESSOR

1.1.

Preventive Maintenance Guide
Intervals are based on the manufacturer’s
recommendations which are expressed in
compressor operating hours.

Intervals listed in this bulletin were converted from compressor operating hours to
mileage using an average vehicle speed of
12.5 mph and a compressor duty cycle of
50%. Adjust the service interval according
to actual operating conditions.
Compressors operating in a hot dusty environment will need more frequent servicing.

PREVENTIVE MAINTENANCE GUIDE
12,000 mi.
(19,300 km)
Compressor
Air Filter
Inspection
(500 hrs.)

Yearly
Compressor
Orbital Scroll
Bearing
Lubrication

48,000 mi.
(77,250 km)

96,000 mi.
(154,500 km)

120,000 mi.
(193,000 km)

400,000 mi.
(644,000 km)

Compressor
Air Filter
Replacement
(2,500 hrs.)

Compressor
Fan & Duct
Seal Cleaning
(4,000 hrs.)

Motor Bearing
Lubrication
(5,500 hrs.)

Discharge Valve
Replacement
(16,000 hrs.)

Crank Pin
Bearing
Lubrication
(4,000 hrs.)
Compressor
Tip & Dust Seal
Replacement
(4,000 hrs.)
Heat Insulation
Pipe
Replacement
(4,000 hrs.)

1.2.
1.2.1.

12,000 Miles (19,300 km)
Preventive Maintenance

1. Remove air filter cover.

Compressor Air Filter Inspection

3. Reinstall filter element and replace cover.

2. Inspect filter element for contamination.

Inspect the air compressor air filter element.

2 of 12

The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2019 New Flyer Industries Canada ULC

SMB-186

SERVICE MANUAL BULLETIN
SMB-186
1.3.

☞NOTE:

Yearly Preventive Maintenance

1.3.1.

Compressor Orbital Scroll Bearing
Lubrication

Pump grease gun to eliminate air from the
extension adapter before use.
4. Apply three full pumps of the grease gun to
deliver the correct amount of grease to the
bearings.

Maintenance of high voltage equipment
must be performed by qualified personnel only. Refer to your New Flyer Service Manual for safety requirements.
Ensure that the High Voltage Interlock
and Battery Disconnect switches are
set to the OFF position and locked-out
and tagged-out.

☞NOTE:

Each pump of the grease gun delivers 0.65
grams of grease.
5. Remove grease gun and reinstall plastic
dust cap.

Lubricate the orbital scroll (OS) bearing
yearly. Lubricate the bearing in the spring
before the high summer temperatures.
If the compressor needs to be removed
from the vehicle to access the lubrication
port, refer to Section 8 of your New Flyer
Service Manual for removal procedure.

/8%5,&$7,21
3257

1. Wipe off around dust cap. Remove plastic
dust cap for orbital scroll bearing grease
fitting. See “Fig. 1: Orbital Scroll Bearing
Lubrication” on page 3.
2. Rotate compressor coupling with a screw
driver until grease fitting lines up with lubrication port.
3. Obtain a grease gun kit with special adapters and grease.

☞NOTE:

Contact New Flyer Parts for information on
the grease gun kit with special adapters
and grease cartridge.

s0700411b.svg

Fig. 1: Orbital Scroll Bearing Lubrication

SMB-186

The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2019 New Flyer Industries Canada ULC

3 of 12

SERVICE MANUAL BULLETIN
SMB-186
1.4.

48,000 Miles (77,250 km)
Preventive Maintenance

1.5.

96,000 Miles (154,500 km)
Preventive Maintenance

1.4.1.

Compressor Air Filter Replacement

1.5.1.

Air Compressor Cleaning, Lubrication
& Parts Replacement

❒ Replace the air filter element.
❒ Remove the fixed scroll cover and clean
the cooling fins using compressed air. See
“Fig. 2: Scroll Compressor Filter Replacement” on page 4.

Maintenance of high voltage equipment
must be performed by qualified personnel only. Refer to your New Flyer Service Manual for safety requirements.
Ensure that the High Voltage Interlock
and Battery Disconnect switches are
set to the OFF position and locked-out
and tagged-out.

),;('6&52//
&29(5
),/7(5(/(0(17

',5(&7'5,9(
02725

s0700571a.svg

Fig. 2: Scroll Compressor Filter Replacement

4 of 12

The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2019 New Flyer Industries Canada ULC

SMB-186

SERVICE MANUAL BULLETIN
SMB-186
1.5.2.

Compressor Fan & Duct Seal Cleaning
Remove the blower fan cover and clean
the compressor fins and fan using compressed air. Wipe the fan duct interior with
a clean cloth.

1.5.3.

Crank Pin Bearing Lubrication

1. Remove scroll compressor assembly from
vehicle. Refer to Section 8 of your New
Flyer Service Manual for removal procedure.
2. Remove the six attaching fasteners and
separate the fixed scroll assembly from the
orbital scroll assembly.
3. Obtain a grease gun kit with special adapters and grease.

☞NOTE:

Contact New Flyer Parts for information on
the grease gun kit with special adapters
and grease cartridge.

*5($6(),77,1*6
)25&5$1.3,1
%($5,1*6

☞NOTE:

s0700407a.svg

Pump grease gun to eliminate air from the
extension adapter before use.
4. Locate the three grease fittings on the
crank pin bearing and apply seven full
pumps of the grease gun to deliver the correct amount of grease to the bearings. See
“Fig. 3: Crank Pin Bearing Lubrication” on
page 5.

☞NOTE:

Each pump of the grease gun delivers 0.65
grams of grease.
5. Reinstall all removed parts.

Fig. 3: Crank Pin Bearing Lubrication
1.5.4.

Compressor Tip & Dust Seal
Replacement

1. Remove the scroll compressor assembly
from the vehicle. Refer to Section 8 of your
New Flyer Service Manual for removal procedure.
2. Remove the hardware from fixed scroll
assembly and separate from orbital scroll
assembly. See “Fig. 4: Scroll Compressor
Assembly” on page 6.
3. Remove old seal. Clean scroll using a
clean cloth and compressed air.

☞NOTE:

Tip seals for fixed scroll and orbital scroll
have opposing seal cut angles. To distinguish between fixed scroll and orbital scroll
seals. See “Fig. 5: Seal Identification” on
page 7.
4. Insert tip seal with lip of the seal (grooved
bottom) facing bottom of scroll seal groove.
Ensure lip faces center of scroll. See “Fig.
6: Orbital Scroll Seal Installation” on
page 7.

SMB-186

The New Flyer vehicles described in this manual may be protected by one or more
patents and design applications or registrations in the United States and Canada,
and in other countries. Refer to “Vehicle Patent Information” in this manual.
Copyright © 2019 New Flyer Industries Canada ULC

5 of 12

SERVICE MANUAL BULLETIN
SMB-186
7. Remove the dust seal and backup tube on
outermost side of fixed scroll set.
During seal installation, it is important
to verify that a notch in the seal has
been achieved. Follow the procedures
carefully to prevent seal movement during installation.
5. Insert a new high pressure tip seal from
the center of the orbital scroll as follows:

8. Insert new backup tube in fixed scroll set.
Orient split in tube to the 6 o’clock position.
See “Fig. 8: Backup Tube Installation” on
page 7.
9. Insert new dust seal on backup tube. Face
seamed section of dust seal at the 3
o’clock position. See “Fig. 9: Dust Seal
Installation” on page 8.

☞NOTE:

a. Make sure there is no gap at the tip,
and that the low pressure seal contacts
the high pressure seal inside the scroll
groove.
b. Insert approximately half of the low
pressure seal and then remove it to verify that a notch in the seal has been
achieved. See “Fig. 7: Seal Installation”
on page 7.
c. Reinstall the portion of the seal
removed previously and complete the
installation of the remainder of the seal.

DO NOT allow dust seal or tip seal to fall
out of position during installation.
10.Reassemble fixed scroll set to orbital
scroll.
11.Install and lightly tighten the six retaining