Installation of the Oil Filter Differential Pressure Switch [CFMI]

TASK 79-35-15-400-040-A
Installation of the Oil Filter Differential Pressure Switch

FIN: 4001EN ** ON A/C NOT FOR ALL

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	OHMMETER MULTIRANGE
No specific	AR	PLIERS - CONNECTOR, JAW, SOFT
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 36 and 32 lbf.in (0.41 and 0.36 m.daN )
No specific	Torque wrench: range to between 100 and 90 lbf.in (1.13 and 1.02 m.daN )
No specific	Torque wrench: range to between 135 and 125 lbf.in (1.53 and 1.41 m.daN )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.CP1041)	isopropyl alcohol
(Material No.CP2244)	primer 1200
(Material No.CP2442)	engine oil
(Material No.CP8001)	lockwire 0.032 in. (0.8 mm) dia.
(Material No.14SBA1)	Textile-Lint free Cotton -
No specific	primer SS-4004
No specific	silicone sealant DC 90-006
No specific	silicone sealant RTV-88

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [1000EM1] (ENGINE-1)
437AL, 438AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
25	PACKINGS	AIPC 79-35-15-01-030

E. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-00-790-001-A	Leak Test of the Accessory-Gearbox (AGB) Carbon Seal
TASK 71-13-00-010-040-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-040-A	Closing of the Fan Cowl Doors
Oil Filter Differential Pressure Switch

3. Job Set-up
Subtask 79-35-15-860-051-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) On the center pedestal, on the ENG panel 115VU, make sure that a WARNING NOTICE(S) is in position to tell persons not to start the engine.
(2) On the overhead maintenance panel 50VU, make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off. Make sure that a WARNING NOTICE(S) is in position to tell persons not to energize the FADEC 1(2).

Subtask 79-35-15-010-053-A ** ON A/C NOT FOR ALL

B. Make sure that the fan cowl doors are open: (Ref. AMM TASK 71-13-00-010-040)
(1) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(2) FOR [1000EM2] (ENGINE-2)
447AL 448AR

Subtask 79-35-15-640-051-A ** ON A/C NOT FOR ALL

C. Lubrication of Packing

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

(1) Lubricate the packings (25) with engine oil (Material No.CP2442) .

Subtask 79-35-15-110-050-A ** ON A/C NOT FOR ALL

D. Cleaning of the switch

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

(1) To be sure of a good electrical bond between the pressure switch (10) and the bracket, clean the mating surfaces with isopropyl alcohol (Material No.CP1041) and a Textile-Lint free Cotton - (Material No.14SBA1) .

4. Procedure
Subtask 79-35-15-910-051-A ** ON A/C NOT FOR ALL

A. Precautions

NOTE: The oil filter differential pressure switch looks like the low oil pressure switch. Installation of the incorrect switch could cause engine damage

Subtask 79-35-15-420-051-B ** ON A/C NOT FOR ALL

B. Installation of the Oil Filter Differential Pressure Switch.
POST SB RA32079-8
(1) Put the bracket (55), thermo barrier (60) and the switch (10) on the mounting bracket and attach them with the bolts (30) and washers (35).
(2) TORQUE the bolts (30) to between 36 and 32 lbf.in (0.41 and 0.36 m.daN )

.
END OF POST SB RA32079-8

Subtask 79-35-15-760-050-A ** ON A/C NOT FOR ALL

C. Do an electrical bond resistance check as follows:

NOTE: Do an electrical bond resistance check at each bolt location.

(1) Put one lead of the OHMMETER MULTIRANGE on the flange of the pressure switch (10) near the bolt (30).
(2) Put the other lead of the ohmmeter on the surface of the bracket.
(3) The resistance measured between the ohmmeter leads must not be more than 0.0025 ohm. Do the check two more times.
(4) If the resistance is more than 0.0025 ohm, remove the pressure switch (10) and clean the mating surfaces again. Do this procedure until the resistance is less than 0.0025 ohm.

Subtask 79-35-15-390-050-A ** ON A/C NOT FOR ALL

D. Seal the electrical bond surfaces
(1) Using of primer

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

(a) Mix the primer 1200 (Material No.CP2244) or primer SS-4004 per the manufacturer's instructions.
(b) Apply a layer of primer to the area around each bolt head and the area around the switch where it touches the bracket.

NOTE: Allow the primer to dry for a minimum of 1 hour or a maximum of 24 hours before you apply the sealant.

(2) Using of sealant

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

(a) Mix the silicone sealant DC 90-006 or the sealant RTV-88 as specified in the manufacturer's instructions.

NOTE: The sealant should not be applied when the temperature is below 50 deg.F (10 deg.C).

NOTE: Use the silicone sealant DC 90-006 with the primer (DC 1200) or silicone sealant RTV-88 with the primer (SS 4004).

(b) Apply a layer of sealant between 0.010 in. and 0.020 in. (0.25 and 0.51 m) thick around each bolt head, and around the pressure switch where it touches the bracket.
(c) Allow the sealant to cure for a minimum of 24 hours, or as specified in the manufacturer's instructions.

NOTE: To decrease the cure time, allow the sealant to cure for a minimum of 2 hours. After 2 hours apply a maximum of 120 deg.F (49 deg.C) heat to the sealant for a minimum of 2 hours.

Subtask 79-35-15-420-052-B ** ON A/C NOT FOR ALL

E. Installation of the union, reducer, hoses, electrical connector and insulation on the switch.
POST SB RA32079-8
(1) Put the AIPC 79-35-15-01-030 PACKINGS (25) on the reducer (15) and the union (20).
(2) Install the reducer (15) and the union (20) in the switch (10).
(3) TORQUE the reducer (15) and union (20) to between 135 and 125 lbf.in (1.53 and 1.41 m.daN )

.
(4) Remove the protective covers from the hose couplings and the switch (10).
(5) Connect the two hoses to the switch (10). TORQUE the couplings on the hoses to between 100 and 90 lbf.in (1.13 and 1.02 m.daN )

NOTE: Use a second wrench to hold the fittings on the switch when you torque the hose couplings.

(6) Remove the protective cover from the connector.
(7) Make sure that all the electrical connections are clean and in the correct condition.
(8) Connect the electrical connector 4001ENA (5) to the switch (10). Tighten the connector with you hand then tighten another 1/8 to 1/4 turn using PLIERS - CONNECTOR, JAW, SOFT.
(9) Put the two halves of the insulation housing (40) on the switch (10).
(10) Use CP8001lockwire 0.032 in. (0.8 mm) dia. to attach the insulation housing (40).
(a) Attach the lockwire to the capstan on the insulation housing (40).
(b) wind the lockwire around the insulation housing and put it between the fittings on the switch.
(c) Attach the other end of the lockwire to the capstan on the opposite side.
(11) Put the insulation boots (45) and (50) on the hoses fittings.
(12) Wind CP8001lockwire 0.032 in. (0.8 mm) dia. around the insulation boots.
END OF POST SB RA32079-8

Subtask 79-35-15-790-050-A ** ON A/C NOT FOR ALL

F. Do these Checks:
(1) Do an idle leak check (Ref. AMM TASK 71-00-00-790-001).
(2) Do a check of the unions for leakage.

5. Close-up
Subtask 79-35-15-410-051-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the fan cowl doors: (Ref. AMM TASK 71-13-00-410-040)
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 03:38:45 UTC