Revision ‘A’ 11 Apr 2014

DHC-8 (DASH 8)

SERVICE BULLETIN 8-24-92

Electrical Power - DC System - Starter/Generator Firewall Terminal

Block Special Inspection and Rectification for Missing Insulating

Sleeves

This page transmits Revision ‘A’ of Service Bulletin 8-24-92, pages 1 thru 14,

dated 11 Apr 2014.

This service bulletin is re-issued in its entirety for the reasons that follow:

- the Effectivity section is revised to change “...with Mod 8/1926/Service

Bulletin 8-24-45 installed.” to “...with terminal blocks P/N 82450075-001

installed.”

- the Compliance section is revised to include reference to TC AD

CF-2014-03

- the References section is revised to convey the latest revision of the service

bulletin and to add reference to TC AD CF-2014-03

- the Procedure section steps (3) and (4) are revised to reflect references to

Figure 1 Sheet 1 and Sheet 2

- Figure 1 is revised for clarity, now consists of two sheets.

Remove the initial issue of Service Bulletin 8-24-92 and replace with

attached.

Previous issue of Service Bulletin 8-24-92:

Initial issue - Pages 1 thru 12 dated 25 Sep 2013.

D

S.B. 8-24-92

Page 1 of 14

25 Sep 2013

NB

Revision ‘A’ 11 Apr 2014

SERVICE BULLETIN

Customer

Support

ATA SYSTEM: 2460 NUMBER: 8-24-92

BOMBARDIER AEROSPACE REGIONAL AIRCRAFT CONSIDER THIS

SERVICE BULLETIN TO BE PARTICULARLY SIGNIFICANT AND

URGE OPERATORS TO PROMPTLY EVALUATE THE CONTENTS

SUBJECT: Electrical Power - DC System - Starter/Generator Firewall Terminal

Block Special Inspection and Rectification for Missing Insulating

Sleeves

1. PLANNING INFORMATION

A. Effectivity

Aircraft Affected:

In-Service: DHC-8 Aircraft Models 102, 103, 106, 201, 202, 301, 311, 314

and 315 Serial Numbers 003 thru 672 with terminal blocks

P/N 82450075-001 installed.

NOTE: The instructions in this service bulletin are only applicable to the systems

and parts installed at the time of delivery on the aircraft or as changed by

Bombardier Aerospace Service Bulletin(s). Before you do this bulletin,

examine all STC or equivalent action changes to make sure this bulletin

can be completed.

Spares Affected:

None
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

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B. Reason

Problem: Investigation after an unsuccessful attempt to start an engine on ground

revealed heat damage on the nacelle firewall P/N 84510222. The damage

was caused by arcing at the forward side of the terminal block P/N

82450075-001.

Cause: The terminal block did not have insulating sleeves installed causing the

terminal block to come in contact with the firewall. This condition could

result in loss of DC generator or inability to start the engine. It can also be

an ignition source due to arcing with the firewall.

Solution: This service bulletin is issued to provide the instructions to inspect the

nacelle firewall and the terminal block and its bushings for damage. It also

provides the instructions to inspect the insulating sleeves to make sure

they are installed and have no damage. Missing or damaged components

are replaced or repaired.

C. Description

The procedures in this service bulletin give the instructions to do the tasks that

follow:

- aircraft is put into standard configuration for maintenance

- aircraft electrical power is removed

- nose landing gear lock is engaged

- main landing gear lock pins are installed thru each main gear and main gear

door mechanism

- work platforms or ladders are set up and properly grounded

- access to firewall terminal block is gained

- inspection of the terminal block for presence of insulating sleeves is done

- installation of the insulating sleeves or replacement of damaged terminal block

assembly is done if necessary

- close out.
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

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25 Sep 2013

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D. Compliance

Bombardier Inc. recommends the accomplishment of this special

inspection/rectification service bulletin at the earliest opportunity unless otherwise

directed by the operator’s airworthiness authority.

Transport Canada Airworthiness Directive CF-2014-03.

E. Approval

The technical content of this service bulletin has been approved under the

authority of the Transport Canada Civil Aviation (TCCA) Design Approval

Organization No: DAO #93-Q-02.

This service bulletin does not affect Airworthiness Limitations (AWLs) or Damage

Tolerance Inspections (DTIs).

F. Manpower

It will take an estimated 2 man-hours to complete this service bulletin. The

breakdown of the man-hours is shown in the table that follows:

TASK MAN-HOURS

Job Set-Up 0.50

Procedure 1.00

Test / RTS 0.00

Close-Out 0.50

For any on-site labor assistance, please speak with a Fleet Services representative

for a quote. The Fleet Services group can be contacted via the Q Series Technical

Help Desk by telephone at 416-375-4000 or email at:

thd.qseries@aero.bombardier.com.

G. Material - Price and Availability

None
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

Page 4 of 14

25 Sep 2013

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H. Tooling - Price and Availability

None

I. Weight and Balance

None

J. Electrical Load Data

Not affected

K. Publications Affected

Maintenance Manual PSM 1-8-2 and ................................

PSM 1-82-2 and

PSM 1-83-2

L. References

Revision ‘A’ of this service bulletin was prepared to the related data that follows:

Mod 8/1926 issue 6 (for reference only)

PCA 07315 Revision 0 (for internal reference only)

Transport Canada Airworthiness Directive CF-2014-03.

2. MATERIAL INFORMATION

A. Parts Required Per Aircraft

Quantity

Per Aircraft

Part Number Description Remarks

2 82450079-101 Insulating Sleeve As required

2 82450079-103 Insulating Sleeve As required

2 82450075-001* Terminal Block

Assembly

As required
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

Page 5 of 14

25 Sep 2013

NB

Revision ‘A’ 11 Apr 2014

*Terminal Block Assembly 82450075-001 already includes one insulating sleeve

82450079-101 and one insulating sleeve 82450079-103. There is one terminal

block assembly per nacelle.

The above parts may be required for the completion of this service bulletin and

may be procured as single items from Bombardier Aerospace Regional Aircraft or

purchased directly from industry sources.

B. Parts Required to Modify Spares

None

C. Special Tools and Equipment Required

None

D. Existing Parts Accountability

None

3. ACCOMPLISHMENT INSTRUCTIONS

A. Job Set-Up

(1) Placard and select all aircraft electrical power to OFF. Obey all relevant

WARNINGS and CAUTIONS (refer to PSM 1-8-2 and PSM 1-83-2 AMM TASKs

12-00-05-00 and 24-00-00-02 and to PSM 1-82-2 AMM TASKs 12-00-05-861-804

and 24-00-00-910-803).

(2) Make sure that lock pins are installed through each main gear and main gear

door mechanism.

(3) Make sure the nose gear ground lock is engaged.

(4) Set wheel chocks in front and behind the landing gear tires.

(5) Set up the work platforms or ladders as required to gain access to LH and RH

Nacelles. Make sure the work platforms or ladders are electrically grounded.
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

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(6) Open the access panels that follow to gain access to firewall terminal block

(number 1 nacelle-2431-1/TB1, number 2 nacelle-2431-2/TB2) (refer to AMM

TASK 06-40-10-00 for locations):

NACELLE UPPER PANEL SIDE PANELS

NUMBER 1 (LEFT) 412DT 415AL, 416AR

NUMBER 2 (RIGHT) 422DT 425AL, 426AR

B. Procedure

NOTE: In this procedure, “damage” is considered to exist if any of the conditions

that follow are found:

- pitting of the firewall or terminal block conductive bushing due to

arcing between the two

- oxidation of the terminal block bushing where the sleeve was missing

- cracked, torn or worn sleeving.

(1) Do a detailed visual inspection of the RHS nacelle firewall 85410222 and

terminal block assembly 82450075-001 as follows (Refer to Figures 1, 2, 3, and

4):

(a) On the forward side of the nacelle firewall, make sure there is no damage

to the nacelle firewall around the terminal block.

(b) Looking from the forward side of the terminal block, make sure the

insulating sleeves are installed on the copper bushings of the terminal

block. Make sure the insulating sleeves are properly installed and have no

damage.

(2) If no damage is found to the nacelle firewall and terminal block and the

insulating sleeves are installed on terminal block and have no damage, do the

Close Out as no corrective action is necessary.

(3) If no insulating sleeves are installed, or the existing sleeves are damaged, and

there is no damage to nacelle firewall and terminal block, install replacement

insulating sleeves as follows (refer to Figure 1 Sheets 1 and 2):

(a) On the forward side of the firewall, disconnect the DC power cables from

the terminal block. Keep the hardware for reinstallation.
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

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(b) Install replacement insulating sleeves 82450079-101 and 82450079-103.

(c) Connect existing 3/8 feeder cable lug on forward side of terminal block

82450075-001 with flat washer NAS1070-616, spring washer B0750-056-S

and nut MS21043-6. Position lug as required and torque bolt. Refer to

torquing procedure. Observe hardware stack-up as shown in Figure 1

Sheet 1.

(d) Connect existing 5/16 feeder cable lug on forward side of terminal block

82450075-001 with flat washer NAS1070-516, spring washer B0625-047-S

and nut MS21043-5. Position lug as required and torque bolt. Refer to

torquing procedure. Observe hardware stack-up shown in Figure 1 Sheet

1.

(e) Refer to Figure 1 and carefully confirm the correct hardware stack up for

each terminal block connection.

(4) If no insulating sleeves are installed and there is no damage to nacelle firewall

but there is damage to terminal block, replace the terminal block assembly as

follows:

(a) Remove damaged terminal block. Discard terminal block and attaching

hardware.

(b) Install replacement terminal block assembly with four bolts NAS5903-12,

washers AN960C10L and nuts MS21043-3 (refer to Figure 1 Sheet 1). Make

sure terminal block conductors are centered in the firewall terminal holes as

the mounting bolts are tightened.

NOTE: Teflon sleeves over terminal block conductors serve to maintain

minimum clearance during the block mounting procedure.

CAUTION: MAKE SURE THAT THE INSULATION SLEEVES ARE

RETAINED ON TERMINAL BLOCK ASSEMBLY DURING

TERMINAL BLOCK INSTALLATION. FAILURE TO DO THIS

COULD RESULT IN DAMAGE TO THE FIREWALL OR NEARBY

EQUIPMENT.
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

Page 8 of 14

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(c) Install existing bus bar 82440059-101 to aft side of terminal using flat washer

NAS1070-616, spring washer B0750-056-S, bolt NAS1306-20 and on the

forward side connect 3/8 feeder cable lug with flat washer NAS1070-616,

spring washer B0750-056-S and nut MS21043-6. Position lugs as required

and torque bolt. Refer to torquing procedure. Observe hardware stack-up as

shown in Figure 1 Sheet 1.

(d) Install existing 5/16 feeder cable lugs on forward and aft side of terminal block

82450075-001 with bolt NAS1305-21, two flat washers NAS1070-516, spring

washers B0625-047-S and nut MS21043-5. Position lugs as required and

torque bolt. Refer to torquing procedure. Observe hardware stack-up shown

in Figure 1 Sheet 1.

(e) Refer to Figure 1 Sheet 1 and carefully confirm the correct hardware stack up

for each terminal block connection.

(5) If no insulating sleeves are installed and damage to the nacelle firewall and

terminal block is found, contact Technical Help Desk by telephone at

416-375-4000 or email at: thd.qseries@aero.bombardier.com for approved

disposition/action.

(6) Repeat steps (1) to (5) for the LHS nacelle firewall and terminal block assembly.

C. Close Out

(1) Remove all tools and equipment from the work area.

(2) Close the access panels that follow (refer to AMM TASK 06-40-10-00 for

locations):

NACELLE UPPER PANEL SIDE PANELS

NUMBER 1 (LEFT) 412DT 415AL, 416AR

NUMBER 2 (RIGHT) 422DT 425AL, 426AR

(3) On completion of this service bulletin, make the following entry in the

appropriate logbooks: “Service Bulletin 8-24-92 (i.e. Electrical Power - DC

System - Starter/Generator Firewall Terminal Block Special Inspection and

Rectification of Missing insulating Sleeves) accomplished.”
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

Page 9 of 14

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Terminal Block Installation

Figure 1 (Sheet 1)

NAS1306--20

BOLT

B0750--056--S

SPRING WASHER

2 REQD

MS21043--6

NUT

NAS5903--12

BOLT

4 REQD

AN960C10L

WASHER

4 REQD

MS21043--3

NUT

4 REQD

NAS1070--516

WASHER

2 REQD

NAS1305--21

BOLT

NAS1070--616

WASHER

2 REQD

MS21043--5

NUT

82440059--101

BUS BAR

82450075--001

TERMINAL

B0625--047--S

SPRING

WASHER

2 REQD

BLOCK ASSY

A

A

B

82450079--101

INSULATING SLEEVE

82450079--103

INSULATING SLEEVE

NACELLE

FIREWALL

2

1

1

2

MS21043--5 FINAL TORQUE =

RUN DOWN TORQUE (IN--LBS) +

65 IN--LBS

MS21043--6 FINAL TORQUE =

RUN DOWN TORQUE (IN--LBS) +

90 IN--LBS

5/16 FEEDER CABLE LUG

3/8 FEEDER CABLE LUG

FWD NACELLE AFT NACELLE

(ROTATED 90 ̊ CW FOR CLARITY)

(ROTATED 90 ̊ CCW FOR CLARITY)

(SEE SHEET 2 FOR DETAILS)
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

Page 10 of 14

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Revision ‘A’ 11 Apr 2014

Terminal Block Installation

Figure 1 (Sheet 2)

NOTE

Trim insulated sleeve

flush with mounting

block after installation.

82450079--101

INSULATING SLEEVE

82450079--103

INSULATING SLEEVE

C

C

SECTION C-C

TERMINAL BLOCK ASSY 82450075-001

BUSHING
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

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A

Terminal Block Inspection

Figure 2

VIEW A

82450079-101

INSULATING

SLEEVE

82450079-103

INSULATING

SLEEVE
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

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Revision ‘A’ 11 Apr 2014

Terminal Block With Insulating Sleeves

Figure 3

INSULATING

SLEEVE

INSULATING

SLEEVE

824500079-101

824500079-103
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

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Terminal Block Without Insulating Sleeves

Figure 4

SIGN OF DAMAGE DUE TO ARCING
SERVICE BULLETIN 8-24-92

S.B. 8-24-92

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This Page Intentionally Blank
Jan 2009

SERVICE BULLETIN (SB) --- RECORD OF INCORPORATION

--- Q SERIES DASH 8 AIRCRAFT

To: CMDB Focal

Facsimile: (1) 416 375 4538

E --mail: cmdb.requests@aero.bombardier.com

From:

Company:

Phone: Extn:

Facsimile: Date:

E --mail:

The data that you provide below will help us record the incorporation of this ModSum

and the aircraft effectivity in the maintenance manual.

Operator: Service Bulletin: __________________ Revision: _________

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Aircraft Serial Number: Model Number: Date Bulletin Completed:

Fax this sheet to (1) 416 375 4538 or Email PDF to:

cmdb.requests@aero.bombardier.com
Feb 2009

SERVICE BULLETIN (SB) --- COMMENT SHEET --- Q SERIES DASH 8 AIRCRAFT

To: SB Focal (Toronto), Bombardier Aerospace Commercial Aircraft

Phone: (1) 416 375 4078 Facsimile: (1) 416 375 4538

E --mail: syed.rizvi@aero.bombardier.com

From:

Company:

Phone: Extn:

Facsimile: Date:

E --mail:

Select appropriate box(es) and add comments or suggestions you would like us to know

that may enhance the quality of our service bulletins.

Service Bulletin: Revision: ModSum:

1. PLANNING INFORMATION

V Effectivity V Reason V Description V Compliance

V Approval V Manpower V Material V Weight and Balance

V Electrical Load V Tooling V References V Publications Affected

2. MATERIAL INFORMATION

V Kit Content V Special Tools/Equipment V Parts to Modify Spares

V Consumables V Disposition of Existing Parts V Other

3. ACCOMPLISHMENT INSTRUCTIONS

V Job Set ---Up V Procedure V Close---Out V Test

V Illustration(s) V Other

4. COMMENTS, REMARKS, SUGGESTIONS

Fax this sheet to (1) 416 375 4538 or Email PDF to:

syed.rizvi@aero.bombardier.com