Bench Test Procedure For A 784B, 784C, 785B, 785C, and 785D Off-Highway Truck Torque Converter{3101} Caterpillar

Off-Highway Truck/Tractor:

784B (S/N: 5RK1-UP)

784C (S/N: 2PZ1-UP)

785B (S/N: 6HK1-UP)

785C (S/N: 1HW1-UP; APX1-UP; 5AZ1-UP)

785D (S/N: DMC1-UP; MSY1-UP)

Introduction

Table 1

Revision	Summary of Changes in REHS3463
01	Added new introduction, Canceled Part Numbers section, and updated effectivity.

© 2011 Caterpillar All Rights Reserved. This guideline is for the use of Cat dealers only. Unauthorized use of this document or the proprietary processes therein without permission may be violation of intellectual property law.

This special instruction contains the necessary information that is required to bench test a specific torque converter arrangement. Refer to Table 2 for the correct arrangements. Bench testing the torque converter ensures correct assembly and operation of the component. Testing a torque converter provides the most conclusive evaluation. Testing allows the dealer to ensure that the torque converter will operate properly in the machine. The specifications in this guideline are specific to bench testing the component. Every effort has been made in order to provide the most current information that is known to Caterpillar. Continuing improvement and advancement of product design might have caused changes to your product which are not included in this publication. This guideline must be used with the latest technical information that is available from Caterpillar.

For questions or additional information concerning this guideline, submit a form for feedback in the Service Information System. In order to address an urgent issue, use the following resources in order to communicate your request to Caterpillar Repair Process Engineering:

• Caterpillar Dealer Technical Communicator

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Table 2

Machine Model	Torque Converter Arrangement
784B	117-3357
784C	117-3357
785B	117-3357
785C	117-3357
785D	117-3357

Canceled Part Numbers and Replaced Part Numbers

This document may include canceled part numbers and replaced part numbers. Use NPR on SIS for information about canceled part numbers and replaced part numbers. NPR will provide the current part numbers for replaced parts.

Collecting The Test Data

Since conditions vary for each test bench, use the data that is collected from your test bench. The collected data is used to compare test results. The data should be collected and maintained by the operator.

Data from each torque converter is collected and stored. Averages from each torque converter arrangement are often used in order to compare values on portions of torque converter tests. Always compare data that is collected from the same torque converter arrangement that is being tested. Averages for the last 20 torque converter arrangements should be maintained.

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Personal injury or death can result from escaping fluid under pressure. Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury. Always use a board or cardboard when checking for a leak.

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Hot oil and components can cause personal injury. Do not allow hot oil or components to contact skin.

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Personal injury or death can result from not following the proper procedures. To avoid the possibility of injury or death, follow the established procedure.

Tools Needed

Note: Pressures will be sensitive to tooling setup. The diameter of the hose, the diameter of a fitting, and additional filtering can affect pressure. The required tools that are listed in Table 3 were used in order to develop this test procedure.

Table 3

Required Tools
Tool	Part Number	Part Description	Qty
A	294-0308	Test Fixture	1
B	1U-5119	Adapter Ring	1
C	1U-5999	Spindle Gp	1
	8B-7997	Bolt (1/2-13 x 2 inch)	4
	3B-4506	Lockwasher	4
D	138-7574	Link Brackets	2
	7X-0343	Bolt (5/8-11 x 1.25 inch)	2
	8T-4122	Hard Washer	2
E	271-3644	Drive Adapter	1
F	0S-1585	Bolt	8
	5P-8245	Washer	8
G	1U-6721	Spindle Adapter	1
H	1U-9131	Adapter Assembly	1
J	1U-9359	Adapter Assembly	1
K	8C-9025	Nipple (Plain)	1
	6B-6765	Elbow (90 degree)	1
	1L-4031	Tee	1
	N1-600S (1)	Needle Valve	1
	6L-7349	Nipple (Pipe)	1
	6V-8733	Fitting (Union)	1
	1U-8300	Fitting (Pipe to Port)	1
	2F-5277	Bushing (Reducer)	1
	1U-9873	Flange (Four Bolt)	1
	8B-7997	Hex Socket Head Bolt (1/2-13 x 2.0)	4
L	6V-7788	Meter (Flow)	1
	6V-7483	Bushing (Reducer)	2
	148-0209	Connector (37 Flared)	1
	281-5848	Connector (37 Flared)	1
M	1U-9873	Flange (Four Bolt)	1
	8B-7997	Bolt (1/2-13 X 2.00 inch)	4
	7B-7138	Elbow (90 degree)	1
	2F-5277	Bushing (Reducer)	1
	8C-9024	Fitting As	1
N	6V-3965	Nipple (Quick Disconnect)	1
O	6V-3965	Nipple (Quick Disconnect)	1
P	6V-8724	Elbow (90 degree)	1
Q	2R-6276	Connector (37 Flared)	1
	6V-5050	O-ring	1
R	6V-3965	Nipple (Quick Disconnect)	1
S	6V-3965	Nipple (Quick Disconnect)	1
T	6V-3965	Nipple (Quick Disconnect)	1
U	1U-6392	Valve (Pressure Rglt)	1
	6V-3966	Fitting As	6
	6V-3965	Fitting As	2
	8T-0856	Gauge (Pressure)	2
	6V-4144	Coupler As	2
	2D-7325	Tee	2

( 1 )

Parker - Hannifin Identification Number

Installation Procedure

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Illustration 1	g01411904

1. Install Tooling (A) .

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Illustration 2	g01411899

2. Install Tooling (B) onto Tooling (A) .

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Illustration 3	g01291592

3. Install Tooling (C) .

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Illustration 4	g01411917

4. Remove pump (1) .

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Illustration 5	g01411921

5. Remove plug (2) .

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Illustration 6	g01411918

6. Remove magnetic filter (3) .

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Illustration 7	g01411396

7. Install Tooling (D) .

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Illustration 8	g01411931

8. Install Tooling (E) .

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Illustration 9	g01411932

9. Use a hoist to install the torque converter on the test bench. The weight of the torque converter is 680.4 kg (1500 lb).

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Illustration 10	g01411936

10. Use Tooling (F) in order to secure the torque converter to Tooling (B) .

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Illustration 11	g01291616

11. Tighten the collet on Tooling (C) in order to connect Tooling (C) to Tooling (E) .

    Note: Refer to Special Instruction, SEHS8763, "Assembly and Operation of 1U-5999 Spindle Group Used for Testing Transmissions on Hydraulic Test Bench" for additional information.

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Illustration 12	g01291622

12. Install Tooling (G) .

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Illustration 13	g01291642

13. Install Tooling (H) .

    Note: Tooling (H) will adapt to the small drive shaft. If the large drive shaft is being used, install Tooling (J) on Tooling (H) .

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Illustration 14	g01291645

14. Align the torque converter with the drive shaft.

15. Connect the drive shaft to Tooling (H) .

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Illustration 15	g01291648

16. Install the drive shaft guard.

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Illustration 16	g01411402

17. Install Tooling (K) .

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Illustration 17	g01412184

18. Install Tooling (L) .

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Illustration 18	g01411413

19. Install Tooling (M) .

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Illustration 19	g01411418

20. Remove plug (4) .

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Illustration 20	g01411421

21. Install Tooling (N) .

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Illustration 21	g01411423

22. Remove plug (5) .

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Illustration 22	g01411427

23. Install Tooling (O) .

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Illustration 23	g01411430

24. Remove plug (6) .

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Illustration 24	g01411431

25. Install Tooling (P) .

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Illustration 25	g01411433

26. Remove plug (7) .

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Illustration 26	g01411435

27. Install Tooling (Q) .

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Illustration 27	g01412187

28. Remove plug (8) .

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Illustration 28	g01411437

29. Install Tooling (R) .

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Illustration 29	g01411438

30. Remove plug (9) .

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Illustration 30	g01411440

31. Install Tooling (S) .

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Illustration 31	g01412192

32. Remove plug (10) .

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Illustration 32	g01411441

33. Install Tooling (T) .

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Illustration 33	g01411442
(11) Supply Oil

34. Connect hose assembly (11) from the pressurized flow meter to Tooling (K) .

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Illustration 34	g01411444
(12) Torque Converter Outlet Flow

35. Connect hose assembly (12) from Tooling (M) to the inlet of the No. 2 flow meter.

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Illustration 35	g01412792
(13) Return To Sump

36. Connect hose assembly (13) from the outlet of the No. 2 flow meter to the test bench sump.

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Illustration 36	g01411452

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Illustration 37	g01411706
(14) Lockup Clutch Oil Supply

37. Connect hose assembly (14) from Tooling (L) to Tooling (Q) .

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Illustration 38	g01411709
(15) Spindle Lubrication

38. Connect lube line (15) from the test bench to Tooling (C). Maintain an oil pressure of 275.8 kPa (40 psi).

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Illustration 39	g01411714
(16) Lockup Clutch Control Supply

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Illustration 40	g01411726

39. Connect hose assembly (16) from Tooling (K) to the inlet of Tooling (U) .

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Illustration 41	g01411734

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Illustration 42	g01411940
(17) Lockup Clutch Signal Supply

40. Connect hose assembly (17) from the outlet of Tooling (U) to Tooling (S) .

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Illustration 43	g01411730
(18) Pressure Reducing Valve Drain

41. Connect hose assembly (18) from Tooling (U) to the drain.

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Illustration 44	g01411943
(19) Lockup Clutch Signal Pressure

42. Connect pressure gauge (19) to Tooling (T) .

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Illustration 45	g01411720
(20) Torque Converter Inlet Relief Pressure

43. Connect pressure gauge (20) to Tooling (N) .

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Illustration 46	g01411941
(21) Torque Converter Outlet Relief Pressure

44. Connect pressure gauge (21) to Tooling (O) .

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Illustration 47	g01411945
(22) Lockup Clutch Pilot Pressure

45. Connect pressure gauge (22) .

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Illustration 48	g01411946
(23) Lockup Clutch Pressure

46. Connect pressure gauge (23) to Tooling (R) .

Test Procedure

Note: The torque converter inlet relief valve and the torque converter outlet relief valve MUST BE tested before the torque converter can be tested. Refer to Testing and Adjusting, SENR6307, "784B and 785B Off-Highway Truck/Tractors Power Train" or Testing and Adjusting, SENR1489, "784C and 785C Off-Highway Truck/Tractors Power Train" for additional information.

Start Checks

Table 4

Oil Requirements
Oil Viscosity	SAE 10W
Oil Temperature	49 °C (120 °F) to 54 °C (130 °F)
ISO Particle Count	16/13

Warm-up Procedure

1. Begin using SAE 10W hydraulic oil. Warm the oil to 50 °C (125 °F). Maintain this temperature for the duration of the test.

2. Turn on the knob Tooling (K) counterclockwise in order to remove any restriction to the inlet flow.

3. Adjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

4. Adjust Tooling (K) clockwise in order to increase the supply pressure to 3447.4 ± 68.9 kPa (500 ± 10 psi).

5. Readjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

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Illustration 49	g02604480

6. Rotate the input shaft in a counterclockwise direction. Adjust the input rotation to 1300 ± 10 rpm.

7. Maintain input speed, oil flow, and pressure for 5 minutes in order to purge the air from the system.

Torque Converter Leakage and Lockup Clutch Pilot Pressure

1. Turn on the knob Tooling (K) counterclockwise in order to remove any restriction to the inlet flow.

2. Adjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

3. Adjust Tooling (K) clockwise in order to increase the supply pressure to 3447.4 ± 68.9 kPa (500 ± 10 psi).

4. Readjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

5. Rotate the input shaft in a counterclockwise direction. Adjust the input rotation to 1300 ± 10 rpm.

6. Record the Torque Converter Inlet Flow in Table 7.

7. Record the Torque Converter Outlet Flow at the No. 2 flow meter in Table 7.

8. Record the Lockup Clutch Pilot Pressure at pressure gauge (22) in Table 8.

Torque Converter Inlet Relief Valve Test

1. Turn on the knob Tooling (K) counterclockwise in order to remove any restriction to the inlet flow.

2. Adjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

3. Adjust Tooling (K) clockwise in order to increase the supply pressure to 3447.4 ± 68.9 kPa (500 ± 10 psi).

4. Readjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

5. Rotate the input shaft in a counterclockwise direction. Adjust the input rotation to 1300 ± 10 rpm.

6. Adjust the load valve on the No. 2 flow meter that is connected to the torque converter outlet until there is visible oil flow from Tooling (P) .

7. Record the Torque Converter Inlet Pressure in Table 9. Reference 930.8 ± 34.5 kPa (135.0 ± 5.0 psi)

Lockup Clutch Test

1. Turn on the knob Tooling (K) counterclockwise in order to remove any restriction to the inlet flow.

2. Adjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

3. Adjust Tooling (K) clockwise in order to increase the supply pressure to 3447.4 ± 68.9 kPa (500 ± 10 psi).

4. Readjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

5. Rotate the input shaft in a counterclockwise direction. Adjust the input rotation to 1300 ± 10 rpm.

6. Adjust Tooling (U) in order to increase the signal pressure at the lockup clutch. The lockup clutch will engage at approximately 1289.3 ± 68.9 kPa (187 ± 10 psi).

7. Record the supply pressure to the lockup clutch at pressure gauge (23) in Table 10. Reference 2138.0 ± 34.0 kPa (310.0 ± 5.0 psi)

8. Record the Lockup Clutch Leakage on Tooling (L) in Table 10.

   Note: Lockup Clutch Leakage must not exceed 15.2 L/min (4.0 US gpm).

9. Adjust Tooling (U) in order to remove all pressure from the Lockup Clutch Signal Supply.

10. Stop rotation of the torque converter.

11. Discontinue all oil flow and pressure to the Torque Converter Inlet.

Lockup Clutch Primary Pressure

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Illustration 50	g01411951

1. Remove cover (24) from the Lockup Clutch Valve Group.

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Illustration 51	g01411952

2. Remove load piston plug (25) .

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Illustration 52	g01411951

3. Reinstall cover (24) .

4. Turn on the knob Tooling (K) counterclockwise in order to remove any restriction to the inlet flow.

5. Adjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

6. Adjust Tooling (K) clockwise in order to increase the supply pressure to 3447.4 ± 68.9 kPa (500 ± 10 psi).

7. Readjust the inlet flow to 159.0 ± 3.8 L/min (42 ± 1 US gpm).

8. Rotate the input shaft in a counterclockwise direction. Adjust the input rotation to 1300 ± 10 rpm.

9. Adjust Tooling (U) in order to increase the signal pressure at the lockup clutch. The lockup clutch will engage at approximately 1289.3 ± 68.9 kPa (187 ± 10 psi).

10. Measure the lockup clutch pressure at Tooling (23) and record the value in Table 11. Reference 1175 ± 35 kPa (170.5 ± 5.0 psi)

11. Adjust Tooling (U) in order to remove all pressure from the Lockup Clutch Signal Supply.

12. Stop rotation of the torque converter.

13. Discontinue all oil flow and pressure to the Torque Converter Inlet.

14. Remove cover (24) from the Lockup Clutch Valve Group.

15. Reinstall load piston plug (25) .

16. Reinstall cover (24) .

Contamination Control

1. Drain all oil from the torque converter.

2. Take an oil sample of the test bench oil supply. Oil contamination must be below ISO 16/13.

3. Record the results in Table 12.

4. Remove the torque converter from the test bench if the test bench oil supply is within specifications.

Specifications

Table 5

General Specifications
Input Speed	1300 ± 10 rpm
Inlet Flow (Torque Converter)	159.0 ± 3.8 L/min (42 ± 1 US gpm)
Supply Pressure	3447.4 ± 68.9 kPa (500 ± 10 psi)
Maximum Torque Converter Leakage	15.2 L/min (4.0 US gpm)
Inlet Relief Valve	930.0 ± 35.0 kPa (135.0 ± 5.0 psi)
Outlet Relief Valve	551.6 ± 34.5 kPa (80 ± 5 psi)
Maximum Lockup Clutch Leakage	15.2 L/min (4.0 US gpm)
Lockup Clutch Supply Pressure	2138.0 ± 34.0 kPa (310.0 ± 5.0 psi)
Lockup Clutch Signal Pressure	1289.3 ± 68.9 kPa (187 ± 10 psi)
Lockup Clutch Pilot Pressure	1725.0 ± 70.0 kPa (250.0 ± 10.0 psi)
Lockup Clutch Primary Pressure	1175 ± 35 kPa (170.5 ± 5.0 psi)

Torque Converter Bench Test Data Sheet

Table 6

CATERPILLAR	Torque Converter Bench Test Data Sheet	Test Date:
		Models: 784B, 784C, 785B, 785C, 785D
Work Order:		Serial No.:

Torque Converter Leakage

Table 7

Torque Converter Leakage
Input Speed (1300 ± 10 rpm) Inlet Flow 159.0 ± 3.8 L/min (42 ± 1 US gpm) Supply Pressure 3447.4 ± 68.9 kPa (500 ± 10 psi)	Inlet Flow (Torque Converter) (1)	L/Min (gpm)
	Outlet Flow (Torque Converter) (2)	L/Min (gpm)
	Leakage (3)	L/Min (gpm)

( 1 )	Measured at the pressurized flow meter
( 2 )	Measured at the No. 2 flow meter
( 3 )	Leakage = Converter Inlet Flow − Converter Outlet Flow

Torque Converter Lockup Clutch Pilot Pressure

Table 8

Lockup Clutch Pilot Pressure (1)
Input Speed (1300 ± 10 rpm) Inlet Flow 159.0 ± 3.8 L/min (42 ± 1 US gpm) Supply Pressure 3447.4 ± 68.9 kPa (500 ± 10 psi)			kPa (psi)

( 1 )

The Lockup Clutch Pilot Pressure is measured at pressure gauge (22) .

Torque Converter Inlet Relief Valve Test

Table 9

Torque Converter Inlet Relief Valve Test (1)
Input Speed (1300 ± 10 rpm) Inlet Flow 159.0 ± 3.8 L/min (42 ± 1 US gpm) Supply Pressure 3447.4 ± 68.9 kPa (500 ± 10 psi)			kPa (psi)

( 1 )

The pressure for the Inlet Relief Valve is measured at pressure gauge (20) .

Torque Converter Lockup Clutch Pressure

Table 10

Torque Converter Lockup Clutch Pressure
Input Speed (1300 ± 10 rpm) Inlet Flow 159.0 ± 3.8 L/min (42 ± 1 US gpm) Supply Pressure 3447.4 ± 68.9 kPa (500 ± 10 psi)	Lockup Clutch Pressure (1)	kPa (psi)
	Lockup Clutch Leakage (2)	L/Min (gpm)

( 1 )	The Lockup Clutch Pressure is measured at pressure gauge (23) .
( 2 )	The Lockup Clutch Leakage is measured at Tooling (L) .

Lockup Clutch Primary Pressure

Table 11

Lockup Clutch Primary Pressure (1)
Input Speed (1300 ± 10 rpm) Inlet Flow 159.0 ± 3.8 L/min (42 ± 1 US gpm) Supply Pressure 3447.4 ± 68.9 kPa (500 ± 10 psi)			kPa (psi)

( 1 )

The Lockup Clutch Primary Pressure is measured at pressure gauge (23) .

Contamination Control

Table 12

ISO Particle Count

Sample the test bench oil supply.

________/________Particle Count

Table 13

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