TJ-241-01 Reduction Gear Main Propulstion RS2719S (1).pdf

T9241-AM-MMO-010 tt.f.f,()J

0910-LP-495-0700

OPERATION AND MAINTENANCE

MANUAL FOR

REDUCTION GEAR,

MAIN PROPULSION RS2719S

MANUFACTURED BY

LUFKIN INDUSTRIES, INC.

P.O.BOX849

LUFKIN, TX. 75901

N00024-89-C-2079

HALTER MARINE INC.

TAGS 51/52

DISTRIBUTION STATEMENT"C": DISTRIBUTION AUTHORIZED TO U.S.

GOVERNMENT AGENCIES AND THEIR CONTRACTORS;ADMINISTRA

TIVE/OPERATIONAL USE: 1 MAY 1990. OTHER REQUESTS FOR THIS

DOCUMENT MUST BE REFERRED TO THE COMMANDER, MILITARY

SEALIFT COMMAND, CODE M-4E WASHINGTON, DC 20390.

WARNING: THIS DOCUMENT CONTAINS TECHNICAL DATA WHOSE

EXPORT IS RESTRICTED BY THE ARMS EXPORT CONTROL ACT

(TITLE 22, U.S.C. SEC 2751 ET.SEC.) OR EXECUTIVE ORDER 12470.

VIOLATIONS OF THESE EXPORT LAWS ARE SUBJECT TO SEVERE

CRIMINAL PENALTIES.

DESTRUCTION NOTICE: DESTROY BY ANY METHOD THAT WILL

PREVENT DISCLOSURE OF CONTENTS OR RECONSTRUCTION OF

THE DOCUMENT.

MILITARY SEALIFT COMMAND

T'1241-AM-MMO-c,10 FOR OFFICIAL USE ONLY

I llllll lllll lllll lllll llll llllllll lllll ll llllll lllll lllll llll llllll lllll lllll lllll llll llll *•'ilO-LP-495-07()0 *

T9241-AM-MMO-010

091 0-LP-495-0700

OPERATION AND MAINTENANCE

MANUAL FOR

REDUCTION GEAR,

MAIN PROPULSION RS2719S

MANUFACTURED BY

LUFKIN INDUSTRIES, INC.

P.O. BOXB49

LUFKIN, TX. 75901

N00024-89-C-2079

HALTER MARINE INC.

TAGS 51/52

DISTRIBUTION STATEMENT"C": DISTRIBUTION AUTHORIZED TO U.S.

GOVERNMENTAGENCIESANDTHEIRCONTRACTORS;ADMINISTRA

TIVE/OPERATIONAL USE: 1 MAY 1990. OTHER REQUESTS FOR THIS

DOCUMENT MUST BE REFERRED TO THE COMMANDER, MILITARY

SEALIFT COMMAND, CODE M-4E WASHINGTON, DC 20390.

WARNING: THIS DOCUMENT CONTAINS TECHNICAL DATA WHOSE

EXPORT IS RESTRICTED BY THE ARMS EXPORT CONTROL ACT

(TITLE 22, U.S.C. SEC 2751 ET.SEC.) OR EXECUTIVE ORDER 12470.

VIOLATIONS OF THESE EXPORT LAWS ARE SUBJECT TO SEVERE

CRIMINAL PENALTIES.

DESTRUCTION NOTICE: DESTROY BY ANY METHOD THAT WILL

PREVENT DISCLOSURE OF CONTENTS OR RECONSTRUCTION OF

THE DOCUMENT.

MILITARY SEALIFT COMMAND

15 JUN 1991

FOR OFFICIAL USE ONLY

RECORD OF CHANGES

Change No. Date Title Or Brief Description Entered By

'0

APPROVALANDPROCUREMENTRECORDPAGE

APPROVAL DATA FOR: T9241-AM-MMO-010

TITLE OF MANUAL: LUFKIN RS2719S REVERSE REDUCTION MARINE GEAR

APPROVAL AUTHORITY: SUPERVISOR OF SHIPBUILDING, CONVERSION AND REPAIR

USN. NEW ORLEANS. LA.

CONTRACT NO_ APPLICABILITY QTY BUILDING YARD

N00024-89-C-2079 TAGS51/52 2 PER HULL HALTER MARINE

REMARKS:

CERTIFICATION DATE: ..:'.(,, llu:;t- 1991

IT IS HEREBY CERTIFIED THAT T9241-AM-MMO-010 TO BE PROVIDED UNDER CONTRACT

NUMBER N00024-89-C-2079 HAS BEEN APPROVED BY THE APPROVAL AUTHORITY

SHOWN ABOVE. ,

?f41, cLdur9~

HALTER MARINE

TECHNICAL MANUAL VALIDATION CERTIFICATE

NA VSEA 4160/3 ( 4-82)

TECHNICAL MANUAL TITLE:

LUFKIN RS2719S REVERSE REDUCTION MARINE GEAR

NAVSEA TECHNICAL MANUAL NUMBER:

T9241-AM-MMO-010

CONTRACT/TMCR NO. :

N00024-89-C-2079

I -VALIDATION

DATE:

15JUN 1991

Except as stated in II, the technical manual identified above has been satisfactorily validated in accordance with all requirements of the ap plicable TMCR and the approved Validation Plan. The technical manual is hereby certified to be accurate and complete, and the information, instructions, text, and illustrations conform in all respects to the applicable general and detailed specifications.

II- EXCEPTIONS

EXCEPTIONS

SIGNATURE OF PUB61CATIONS QUALITY ASSURANCE OFFICER:

/\---) c,-<i-, / . ·-- .

AUTHORIZED BY

DATE:

f. -i,,~-'i I ' . .

C)

T9241-AM-MMO-010

FOREWORD

This technical manual includes installation, operation, maintenance, andrepairinstructions, with a parts list for the LUFKIN RS2719S REVERSE REDUCTION MARINE GEAR. The manual covers the following:

Chp.

No. Title

1. General Information and Safety Precautions

2. Operation

3. Functional Description

4. Scheduled Maintenance

5. Troubleshooting

6. Corrective Maintenance

7. Parts List

8. Installation

Ships, training activities, supply points, depots, naval shipyards, and Supervisors of Shipbuild ing are requested to arrange for the maximum practical use and evaluation of NA VSEA technical manuals. All errors, omissions, discrepancies, and suggestions for improvement to NA VSEA technical manuals shall be reported to the Naval Sea Data Support Activity (NSDSA), Naval Ship Weapon Systems Engineering Station (Code 5H21.5), Port Hueneme, CA 93043 on NA VSEA Technical Manual Deficiency/Evaluation Report, NA VSEA Form 9086/10. To facilitate such reporting, three (3) copies of NA VSEA Form 9086/10 are included at the end of the bound part of each newly published unclassified technical manual. All feedback comments shall be thoroughly investigated and originators will be advised of action resulting therefrom.

Extra copies of NA VSEA Form 9086/10 may be requisitioned from the Naval Publications and Forms Center (NPFC), Philadelphia, PA 19120.

T9241-AM-MMO-010

WARRANTY

The Manufacturer will warranty this equipment against any defects or deficiencies in workmanship and/or material through the period of time that the vessel this equipment is installed on is completed, finally accepted by the Navy, and subsequently performs nine (9) months continuous service or nine (9) months of cumulative service in the event the vessel is disabled because of any equipment failure.

T9241-AM-MMO-010

TABLE OF CONTENTS

CHAPTER/PARAGRAPH PAGE

TABLE OF CONTENTS . . . . . . . . . . . . . . . . . . . . ... i LIST OF ILLUSTRATIONS . . . . . . . . . . . . . . . . . . . . iii LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . iv SAFETY SUMMARY ........................ v

1 GENERAL INFORMATION AND

SAFETY PRECAUTIONS ................... 1-1

1-1 INTRODUCTION .................... 1-1

1-2 MANUALAPPLICABILITY .............. 1-1

1-3 TECHNICAL INFORMATION AND

SPECIFICATIONS .................... 1-1

1-4 POWERTRANSMISSION ............... 1-6

1-5 SAFETY PRECAUTIONS ................ 1-8

2 OPERATION .......................... 2-1

2-1 11'-!TRODUCTION . . . . . . . . . . . . . . . . . . . . 2-1

2-2 CONTROLSANDINDICATORS ............ 2-1

2-3 INITIALSTART-UP ...... : ............ 2-1

2-4 OPERATIONALPROCEDURE ............. 2-1

3 FUNCTIONAL DESCRIPTION ................ 3-1

3-1 INTRODUCTION .................... 3-1

3-2 GENERAL ........................ 3-1

3-3 GEAR HOUSING .................... 3-1

3-4 GEARING . . . . . . . . . . . . . . . . . . . . . . . . 3-2

3-5 BEARINGS AND BEARING CARRIER . . . ..... 3-2

3-6 LUBRICATION ..................... 3-2

3-7 CLUTCHES ....................... 3-4

3-8 FLEXIBLE COUPLING . . . . . . . . . . . . . . . . . 3-4

4 SCHEDULED MAINTENANCE ................ 4-1

4-1 INTRODUCTION .................... 4-1

4-2 GENERAL ........................ 4-1

4-3 MAINTENANCEPLAN ................. 4-1

T9241-AM-MMO-010

TABLE OF CONTENTS (Cont'd)

CHAPTER/PARAGRAPH ................... PAGE

4-4 OIL PUMP MAINTENANCE . . . . . . . ....... 4-3

4-5 CLUTCH INSPECTION . . . . . . . . . . . . ..... 4-3

4-6 RECOMMENDED PRACTICE FOR PRESERVING

GEAR TEETH & BEARINGS DURING

INOPERATIVE PERIODS ................ 4-3

5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . 5-1

5-1 INTRODUCTION .................... 5-1

5-2 TROUBLESHOOTING . . . . . . . . . . . . ..... 5-1

6 CORRECTIVEMAINTENANCE ..... .I . ........ 6-1

6-1 INTRODUCTION .................... 6-1

6-2 GEAR DISASSEMBLY ................. 6-1

6-3 GEAR INSPECTION . . . . . . . . . . . . . . ..... 6-4

6-4 GEAR ASSEMBLY ................... 6-5

6-5 OIL PUMP REPLACEMENT .............. 6-7

6-6 CLUTCH REP AIR . . . . . . . . . . . . . . . . . . . . 6-9

6-7 REPLACEMENT OF FLEXIBLE COUPLING

SEGMENTS . . . . . . . . . . . . . . .- . . . . . . . 6-11

7 PARTSLISTS ......................... 7-1

7-1 INTRODUCTION .................... 7-1

7-2 GENERAL ......................... 7-1

7-3 EXPLANATIONOFPARTSLIST ........... 7-1

7-4 PARTS LISTS ...................... 7-1

7-5 LISTOFMANUFACTURERS ............ 7-26

8 INSTALLATION ........................ 8-1

8-1 INTRODUCTION .................... 8-1

8-2 ALIGNMENT OF GEAR OUTPUT SHAFT

TO TAILSHAFT ..................... 8-1

8-3 MOUNTING OF INPUT COUPLING . . . ....... 8-1

8-4 CLUTCH ALIGNMENT INSTRUCTIONS ....... 8-8

8-5 ENGINE/GEAR ALIGNMENT . . . . . . ....... 8-9

8-6 GEAR TOOTH ALIGNMENT ............. 8-12

ii

T9241-AM-MMO-010

LIST OF ILLUSTRATIONS

FIGURE DESCRIPTION PAGE

1-1 2-1 6-1 6-2 6-3 6-4 7-1 7-2 7-3 7-4 7-5 7-6 7-7 7-8 7-9 7-10 7-11 7-12 7-13 7-14 7-15 8-1 8-2 8-3 8-4 8-5 8-6 8-7 8-8

8-9

Lufkin RS2719S Reverse Reduction Gear ...... 1-7 ReliefValve ...................... 2-2 Tuthill Oil Pump ................... 6-3 Tuthill Oil Pump . . . . . . . . . . . . . . . . . . . 6-8 Eaton Marine Clutch . . . . . . . . . . . . . . . . . 6-10 Removing Flexible Segment . . . . . . . . . . . . . 6-12 Aft (Output) End View . . . . . . . . . . . . . . . . 7-11 Port Side View .................... 7-12 STBD Side View . . . . . . . . . . . . . . . . . . . 7-13 FWD (Input) End View ................ 7-14 Detail C-C of Figure 7-4 ............... 7-15 Detail A-A of Figure 7-4 ............... 7-16 Section C-C of Detail A-A ......... ; .... 7-17 Section D-D of Detail A-A .............. 7-18 Detail A-A (Auxiliary) of Figure 7-4 ......... 7-19 Section B-B of Detail A-A (Auxiliary) ........ 7-20 Section E-E of Detail A-A (Auxiliary) ........ 7-21 Section F-F of Detail A-A (Auxiliary) ........ 7-22 Reverse & Forward Oil Pump Detail . . . . . . . . . 7-23 Marine Gear Clutch Assembly ............ 7-24 Flexible Coupling ................... 7-25 Radial Alignment ................... 8-3 Axial Alignment . . . . . . . . . . . . . . . . . . . . 8-4 Angular Alignment . . . . . . . . . . . . . . . . . . 8-6 Spring Pin Positoning . . . . . . . . . . . . . . . . . 8-7 Measuring Clutch Air Manifold Runout . . . . . . . 8-9 Measuring Input Shaft End Play . . . . . . . . . . . 8-11 Flexible Coupling . . . . . . . . . . . . . . . . . . . 8-13 Lufkin RS2719S Reverse Reduction Marine Gear (STBD & AFT View) . . . . . . . . . . . ... 8-14 Lufkin RS2719S Reverse Reduction (FWD & Port View) ................. 8-15 iii

C) LIST OF TABLES

TABLE DESCRIPTION PAGE

1-1 Specifications . . . . . . . . . . . . . . . . . . . . . 1-1 1-2 Bearings ........................ 1-3 1-3 Shafts ......................... 1-3 1-4 Herringbone Gears - 30° Helix 20° Pressure Angle .1-3 1-5 Auxiliary Equipment ................. 1-4 1-6 Double Helical Gears - 20° Pressure Angle . . . . . . 1-4 5-1 Clutch Troubleshooting ................ 5-3 7-1 RS2719S Parts List .................. 7-2 7-2 Marine Gear Clutch Assembly Parts List ....... 7-7 7-3 Marine Gear Clutch Assembly Parts List ....... 7-8 7-4 Flexible Coupling Parts List . . . . . . . . . . . . . 7-9 8-1 Alignment Tolerances (inches) ............ 8-3 iv

T9241-AM-MMO-010

SAFETY SUMMARY

The following are general safety precautions that are not related to any specific pro cedures and therefore do not appear elsewhere in this publication. These are recom mended precautions that personnel must understand and apply during many phases of operation and maintenance.

WARNING notices are used to warn personnel about procedures which must be fol lowed for the protection of personnel. Failure to comply may result in injury or death to personnel.

CAUTION notices are used to warn personnel about procedures which must be fol lowed for protection of equipment. Failure to comply may result in damage to equip ment.

KEEP AWAY FROM LIVE CIRCUITS

Operating personnel7Tlust at all times observe all safety regulations. Do not replace components or make adjustments inside the equipment with the high voltage supply energized. Under certain conditions, dangerous potentials due to the charges retained by the capacitors may exist when power is off. To avoid casualties, always disconnect the power and discharge the circuit before touching it.

DO NOT SERVICE OR ADJUST ALONE

Under no circumstance should any person reach into an enclosure for the purpose of servicing or adjusting the equipment when not in the company of someone who is capable of rendering aid in the event of accidental shock.

REDUCE RISK OF ACCIDENTAL SHOCK

Personnel working with or near high voltage should remove watches, rings or any jewelry that could accidentally make physical contact with circuits.

RESUSCITATION

Personnel working with high or near high voltage should be familiar with modern methods ofresuscitation. Such information may be obtained from the Bureau of Medicine and Surgery.

WARNING AND CAUTIONS

The following warnings and cautions appear in this technical manual, and are , repeated here for emphasis.

V

T9241-AM-MMO-010

CAUTION

Operation of the gear with low oil level could result in damage to the equipment.

CAUTION

Operation using only splash lubrication should be limited to emergency situations and should be limited to half propeller speed.

If speeds over half speed are used, care must be taken not to overheat the oil. If the oil pump is not working, oil will not be going through the heat exchanger, and the ther mometer will not be useful in monitoring oil temperature.

CAUTION

Marine Reduction Gears are precision made to extremely close tolerances. Operating the gear under casualty conditions may cause extensive equipment damage. It is recom mended that the gear be stopped whenever unusual noise, vibration, or loss of lubricat ing oil is detected, and the cause be deter mined and corrected before restarting.

II WARNING II

Care should be taken to insure that the main or auxiliary propulsion engines do not turn the gear unit while maintenance is underway on the gear as personal injury or loss of life could occur.

II WARNING II

Care should be taken to insure that all electri cal power connected to the gear is discon nected while maintenance is underway on the gear. Failure to do this could result in per sonal injury or loss of life.

vi

T9241-AM-MMO-010

CAUTION

Ensure lifting lines and lifting device are rated for load. Ensure lifting lines do not bear on lubricating lines.

CAUTION

Too little end play in the pump pinion could result in failed pump gear bearings. To in crease the pump gear end play, place 0.032 inch shim between the pump adapter and the pump housing.

II WARNING II

Contains asbestos fibers. Avoid creating dust. Breathing asbestos dust may cause serious bodily harm.

CAUTION

All four flexible segments must be replaced as a set.

CAUTION

Do not exceed 500°F when heating hub.

CAUTION

Ensure segments are centered by the fitted bolts. Ensure segment makes full contact with the ten.sion ring.

CAUTION

Ensure segments makes contact with the connecting parts.

CAUTION

Do not use porta-power units to shift the shaft as the bearing retainer that secures the retained bearing could be damaged.

vii

1'9241-AM-MMO-010

CHAPTERl

GENERAL INFORMATION AND SAFETY

PRECAUTIONS

1-1 INTRODUCTION

This chapter contains general information, technical specifications and safety precautions for the Lufkin RS2719S Reverse Reduction Marine Gear.

1-2 MANUAL APPLICABILITY

This manual applies only to the Lufkin Model RS2719S Reverse Reduction Marine Gear, Serial numbers 7121 and 7122, as installed on TAGS-51 and TAGS-52.

1-3 TECHNICAL INFORMATION AND SPECIFICATIONS

The following tables give technical data and specifications for the Lufkin RS2719S Reverse-Reduction Marine Gear.

Table 1-1. Specifications

Gear Model No.

Serial Numbers

Item

Service Horsepower - Main Engine Auxiliary Engine

Input Speed RPM

Ratios (Input to Output) 1st FWD (Ahead) Reverse (Astern)

Thrust Bearing End Play (inches)

Input Shaft End Play - Main Engine Auxiliary Engine

Clutch Apply Pressure PSI (all clutches)

Lube Oil

Sump Capacity (gallons)

1-1

Specification

RS2719S

1121n122

4.026 4.223

.006- .011

7121 (.048) 7122 (.054) 7121 (.060) 7122 (.055)

Mobil Gear 630, ASTM#

"!':Wl!-AM-MMU-U!U

Table 1-1. Specifications (Cont'd)

Item

Heat Exchanger Data:

Heat Rejection Rate (BTU/HR) Cooling Water Flow (GPM) Cooling Water Temp. °F (inlet) Water Pressure Drop (PSI) Tube Material

Lube Oil Low Pressure Alarm Set Point (PSI)

Lube Oil High Temp. Alarm Set Point (°F)

Gear Unit Dry Weight (LBS) Gear Unit Wet Weight (LBS)

Clutch Data:

Controlled Inflation Time (0-50 PSI) Final Inflation Time (50-150 PSI)

Engine RPM During Controlled Inflation (maximum)

Engine Gov. Response Point (Inflation Pressure)

Engine Gov. Response Time (Final Inflation Rate)

Clutch Exhaust Time (maximum)

Air Supply Line Size: 12 VClOOO 24 VClOOO

Friction Lining Thickness (new) 12VC1000

24VC1000

Replace at 12VC1000

24VC1000

Drum Diameter 12VC1000

24VC1000

Type Fastener 12VC1000 + 24VC1000

Oil Pump Data: Size End Play Capacity

Bushing Ream Size (Bushing No. E7058923)

Recommended Tightening Torques Nominal Size: 1/2

5/8 3/4 1-1/4 1-1/2

1-2

Specification

129,795 90° 1.5

90110 CUN!

27,000 27,885

3 seconds 1-2 seconds

1.25 x Idle RPM

Greater than 50 psi

More than 2 seconds

1 second

3/8" O.D.

1/2" O.D.

21/64 inches 29/64 inches 5/32 inches 5/32 inches 11-29/32 inches 23-7 /8 inches Rivets

5RCSA

.003/.005 inches 61gpm

1.001/1.002

30 ft. lbs.

58 ft. lbs.

96 ft. lbs.

242 ft. lbs.

535 ft. lbs.

855 ft. lbs.

Table 1-1. Specifications (Cont'd)

Item Specification

Auxiliary Oil Pump Data:

Manufacturer I.M.O. Delaval Inc.

Rotation C/W (clockwise)

Body Material Cast Iron

Rotor Size 143

Capacity 18.5 GPM at 1750 RPM

Discharge Pressure 25PSI

Auxiliary Oil Pump Motor Data:

Horsepower 5

Speed 1800RPM

Frequency 60Hz

Frame 184TC

Volts 230/480V

Phase 3

Enclosure TEFC (Totally Enclosed Fan Cooled)

1-3

Note: Refer to Figure 1-1 when using Tables 1-2 through 1-6

Table 1-2. Bearings

Mark Description Qty.

Bl Thrust BRG. AP10324 1

B2 Bearing 23052 1

B3 Bearing 23040 4

B4 Bearing 22230 4

BS Bearing 22228 2

B6 Bearing 22218 1

B7 Bearing 6215 3

Table 1-3. Shafts

0 Mark Description Hardness WR2 (F'r'LBS)

15 LSPShaft 270-312 178

16 HS Shaft 270-312 21

17 HS Shaft (Aux.) 270-312 2

18 Rev. Idler Shaft 270-312

19 HS GR Shaft (Aux.) 270-312 16

Table 1-4. Herringbone Gears - 30° Helix 20° Pressure Angle

Mark P.D. D.P. No. Ratio Material Effect Actual BHN ~:S) Teeth J:1ace Widtl Face Width Hardness

6 24.571 3.5 86 1.051 414SH 9 3/4 101/4 300-34: 689

inches inches inches inches

7 23.429 3.5 82 1.051 414SH 9 3/4 101/4 300-34'. 588

0 inches inches inches inches

1-4

1 !1~'t 1-J-UV1-!VllV1V-V 1V

Table 1-5. Auxiliary Equipment

Mark Description Material BHN 2

~BS) Hardness

8 Coupling, Output (BM098077) Alloy Cast S tee! 217-259 193

9 Clutch Adapter (BM102758) Alloy Cast Steel 225-267 6

11 Clutch, 24VC1000 (Outer Element) - - 1794

12 Clutch, 24VC1000 (Drum) - - 416

13 Clutch, 12VC1000 (Outer Element) - - 96

14 Clutch, 12VC1000 (Drum) - - 25

10 Clutch, Adapter (BM119557) Alloy Cast S tee! 225-267 56

20 Retainer, T-BRG (AM022320) Alloy Cast Steel 225-267 5

21 Retainer, LSP CPLG (AM022320) Alloy Cast S tee! 225-267 5

Table 1-6. Double Helical Gears - 20° Pressure Angle

Marlc: P.D. D.P. No. Ratio Material Helix Effect Face Actual BHN ~~S) Teeth Angle Width Face Width Hardness

1 43.257 4 153 4.031 4140(R]M) · 27° 50' 22.2" 19 211/1. 300-342 5153 inches inches inches inches

2 10.743 4 38 4.031 4145H 27° 50' 22.2" 19 211/1. 350-392 69 inches inches inches inches

3 10.743 4 38 4.031 4340H 27° 50' 22.2" 19 211/1. 350-392 65 inches inches inches inches

4 33.143 4 116 2.231 4140(RIM) 28°57' 18.1" 8 10 1/2 350-392 1145

inches inches inches inches

5 14.857 4 52 2.231 4145H 28° 57' 18.1" 8 101/2 350-392 90 inches inches inches inches

1-5

1-4 POWER TRANSMISSION

The following is a detailed description of how the power is transmitted through a Marine Gear train. This particular description refers to the RS2719S. All references are to Figure 1-1.

Power is transmitted to the Input Shaft Number 16. Gear 7 turns with the input shaft Number 16 and it also meshes with Gear 6. Both Gears, 6 and 7, will turn at all times that the Input Shaft Number 16 is turning.

1-4.1 Forward Condition

When the clutch on the ouput side of the gearbox is engaged, Pinion 2 and Gear 4 begin turning. Pinion 2 will drive the Bull Gear 1, which drives the Output Shaft 15. The output shaft will be turning in a direction opposite to the direction which the input shaft is turning.

This is the fory.,ard drive condition.

Because Gears 4 and 5 mesh, anytime the output side clutch is engaged, the auxiliary high speed shaft number 19, also turns in a direction opposite the input shaft.

Gear 1 and Pinion 3 also mesh, so the bull gear drives the pinion. This causes Pinion 3 to turn in the same direction as Pinion 2. Because Gears 6 and 7 mesh, they rotate in opposite directions. Therefore, the Idler Shaft Number 18 which keyed to Gear 6, turns in a direction opposite t o that which Pinion 3 turns. Also, the clutch on the input side of the gearbox, has parts 11 and 12 turning in opposite directions.

1-4.2 Reverse Condition

When the clutch on the input side of the gearbox is engaged, and the clutch on the ouput side of the gearbox is not engaged and the box run~ in a reverse direction. The Gear 6 drives the Idler Shaft Number 18 turning the outer part of the clutch in a direction opposite to the input shaft direction. The clutch on the input side of the gearbox now turns the shaft of which Pinion Number 3 is integral in a direction opposte of the input shaft. Pinion 3 drives Bull Gear Number 1 which results in an output in the same direction as the input shaft. Bull Gear 1 now drives Pinion 2.

Pinion 2 is rotating in a direction opposite to the direction of the Input Shaft Number 16.

Gear 4 rotates in the same direction as Pinion 2; Gear 5 rotates in a direction opposite to Pinion 2, and therefore is rotating in the same direction as input shaft Number 16. Gear 5 turns Shaft Number 19.

1-4.3 Auxiliary Drive

This mode of operation should only occur with both forward and reverse clutches are disconnected. Power is transmitted from the auxiliary engine/gear drive to the LUFKIN Shaft Number 17. This shaft if connected to the inner part of the Auxiliary Clutch Number

14. When this clutch is engaged Items 13 & 14 turn as an assembly. Item 13 is connected through Clutch Adapter Item 9 to Auxiliary Shaft Number 19. This shaft drives Pinion 5.

These parts are all turning as a unit with the ouput from the Twin Disc Drive.

Pinion 5 is in mesh with Gear 4 mounted on Pinion Shaft 2. Pinion Shaft 2 then drives Bull Gear 1 and Output Shaft 15.

Reverse direction from the auxiliary engine is provided by a separate marine reverse reduction gear.

1-6

CJ

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14.M G.D

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-/l\J"l-

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1 1/4 X 118 X 6 318, TWO KEYS .,acr v ~

I 1'4 X 718 X 8 fl.[Y

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TWO K[YS I 114 l 711 l • . , ...

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1'9241-AM-MMO-010

N

Figure 1-1. Lufkin RS2719S Reverse Reduction Gear

1-7

(View Looking UP!)

Forward

Port Side Starboard Side

AFT

1'9241-AM-MMO-010

1-5 -SAFETY PRECAUTIONS ,

Safety precautions, highlighted as WARNING or CAUTION, are positioned near the applicable text throughout this manual. In addition, a complete listing of all the WARNING and CAUTIONS is contained in the SAFETY SUMMARY in the front matter of this manual.

Every effort has been made to place the warning and cautions in the appropriate parts of this text, but it is strongly recommended that the safety summary be reviewed before attempting to install, service, repair, or operate this equipment.

1-8

·1~:t'll-AM-MMU-UlU

CHAPTER2

OPERATION

2-1 INTRODUCTION

This chapter provides information and operating instructions for the Lufkin RS2719S Reverse-Reduction Marine Gear.

2-2 CONTROLS AND INDICATORS

All controls and indicators are fully integrated into the main propulsion engine controls and the central machinery control system monitoring and alarm system.

2-3 INITIALSTART-UP

The gear unit is shipped from the factory dry. Before starting the unit, fill the sump to the required quantity, as indicated on the nameplate and dipstick. At the time of shipment, LUFKIN coats interior gear parts with a rust preventative oil. This oil should be compatible with the operating oil, and it should not be necessary to flush the unit prior to putting in lubricating oil. Filling can be accomplished through one of the inspection covers on top of the gear case. Use clean oil and strain through a 100 mesh wire cloth or filter, if possible.

This marine gear is designed to use an AGMA #SEP lubricant which should have viscosity from 918 to 1120 SSU at 100°F. The oil should be a high quality, well-refined petroleum oil with rust and oxidation inhibitors and an anti-foam additive. The preferred minimum viscosity index is 90.

The lube oil must be suitable for use in a gear box. The oil must have non- corrosive characteristics to steel, brass, aluminum and cast iron even in the presence of moisture. None of the additives mentioned above can act as abrasives.

2-4 OPERATIONAL PROCEDURE

a. Check the gear dipstick to verify that the gear sump is full of oil.

CAUTION

Operation of the gear with low oil level could result in damage to the equipment.

b. Start the engine and run it at idle speed. Check the gear lubricating oil pressure immediately. If the pressure does not pick up within the first minute or two, shut the unit down and determine the cause. When oil circulation is achieved, set the main oil header pressure control valve at 30 to 35 psi operating pressure by means of the adjusting screw on the relief valve (Figure 2-1) at full engine speed.

c. Check the oil temperature and make adjustments in cooling water supply to maintain the oil temperature between 120° and 140°F. After initial start-up and shutdown, or when unit has been drained. Check the oil level and add oil as required to replace the volume absorbed by heat exchanger, filters, and piping. The oil level can only be measured with the unit shut down.

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d. After temperature has stabilized, re-check pressure to insure pressure is between 30 to 35 psi at full engine speed. This pressure will fall when engine speed is reduced, but sufficient oil will be supplied to bearings and gear meshes at pressures as low as 5 psi.

e. If the oil pump cavitates during operation, the oil level should be raised and the dip stick re-marked. On units furnished with high temperature-low pressure alarm switches, the switches have been pre-set at the factory. (Temperature switches are set to alarm at 170°F. Pressure switches are set to alarm at 10 psi.)

AdJustin under ca g p

RELIEF VALVE

Screw located

•N

Figure 2-1 Relief Valve

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CHAPTER3

FUNCTIONAL DESCRIPTION

3-1 INTRODUCTION

This chapter provides a functional description of the Lufkin RS2719S Reverse Reduction Marine Gear and is broken down into the following sections:

a. General

b. Gear Housing

c. Gearing

d. Bearings and bearing carriers

e. Lubrication

f. Clutches

3-2 GENERAL

The LUFKIN Reverse-Reduction Marine Gear is capable of transmitting full engine horsepower to the propeller shaft. By engaging either the forward or astern clutch, the output shaft direction of rotation can provide either ahead or astern vessel motion.

The gear teeth are designed for optimum reliability taking into account both tooth bending strength and surface contact stress durability. The gear teeth are designed to American Bureau of Shipping and AGMA specifications (1.6 minimum AGMA service factor).

The unit is equipped with a self-contained lubrication system suitable for distributing filtered and cooled oil to the various bearings and gear meshes. In addition the low speed gear runs in a bath of oil. This action not only lubricates the gear but also splashes oil throughout the gear box which is collected in oil troughs and distributed to the bearings.

3-3 GEAR HOUSING

The gear housings are made up of three major parts: the sump with mounting flanges, the center section and the cover. They are made of close-grained cast iron or fabricated steel which has been fully stress relieved. Housings are split at each shaft for easy access to rotating elements and bearings. The housing bores are machined on numerically controlled boring mills to obtain bore parallelism. Heavy ribbed sections are utilized to maintain proper internal gear alignment

Inspection covers are provided for inspection and examination of all gear components, with a breather provided in one cover to maintain atmospheric pressure inside the gear housing.

3-1

3-4 GEARING

The gearing is double helical design precision manufactured using the Hobbing or Sykes cutting method. Gear ratings are based on AGMA and applicable marine classification societies' rating formulas (ABS, Lloyd's, etc.). Conservative service factors are applied to the seratings to insure long gear life. Gearing is made from high tensile strength, through hardened alloy steel forgings, which have been thoroughly stress relieved and heat treated to provide low working stresses and dependability. The bullgear and its shaft are statically balanced, while the other elements are dynamically balanced.

3-5 BEARINGS AND BEARING CARRIER

All shaft support bearings are self-aligning spherical roller bearings. The thrust bearing is a double row tapered roller bearing designed to transmit full propeller thrust in both forward and astern modes to the ship structure. All bearings are conservatively rated, having an average design life, based on full load conditions, in excess of 100,000 hours.

All shaft support bearings are mounted in replaceable cartridges or bearing carriers which are mounted in the gear housing bores. This design eliminates any wear to the gear housing due to bearing outer race movement and eliminates costly housing reboring.

3-6 LUBRICATION

Each gear is equipped with a self-contained lube oil system that provides cooled and filtered oil to the gearing and bearings. The bull gear runs in a bath of oil in the sump. The oil that is splashed by the bull gear is collected in oil troughs which distribute the oil to all bearings.

In addition to this splash system, the unit is equipped with a pressurized oil system which circulates the oil through the filter and heat exchanger and furnishes oil to the gear mesh Q sprays and bearing supply troughs. It consists of the following parts.

a. Suction Strainer - This strainer protects the oil pump from foreign particles that might be in the gear sump.

b. Check Valve -This valve is used to maintain the oil pump prime during inoperative periods.

c. Oil Pump - The gear driven oil pump is a Tuthill model which has an automatic reversing feature. The pump is designed to maintain constant direction of flow from the same pump port regardless of the direction of shaft rotation.

The internal gear principle is based on the use of a rotor, idler gear and crescent partition. Only two moving parts comprise the pumping element.

Power is applied to the rotor and transmitted to the idler gear with which it meshes.

The space between the outside diameter of the idler and the inside diameter of the rotor is sealed by the crescent. When the pump is started, there is an increase of volume as the teeth come out of mesh. This creates a partial vacuum drawing the oil into the pump through the suction port. The oil fills a space between the teeth of the idler and rotor, and is carried past the crescent partition to the pressure side of the pump. When the teeth mesh on the pressure side, oil is forced from the spaces and out through the discharge port.

When the direction of shaft rotation changes, the idler carrier (including the idler gear and crescent) automatically rotates 180° through suction zone which changes the

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1'9241-AM-MMO-010

direction of flow within the pump without changing port position. The idler carrier rotates in a cover casting fitted with stops so that the crescent can rotate only 180° -always through the suction zone.

There is also a motor driven auxiliary lube oil pump. This pump is a positive displacement type pump, it is used for circulating oil before start-up and in emergency conditions. Refer to figure 8-8.

d. Filter - The oil filter is a canister type with a replaceable 40 micron synthetic element.

The filter is equipped with an internal bypass which allows a portion of the pumped oil to circumvent the filter if the oil is unusually thick due to cold temperatures. A 149 micron wire-mesh filter element is available on special request which can be cleaned and reused.

e. Heat Exchanger - Each gear is equipped with a tube and shell heat exchanger for cooling the lube oil. It has either 3/8" admiralty tubes for use with 120° fresh water or 5/8" 90/10 cupro nickel tubes for use with sea water. Special cooler materials are available if required.

f. Relief Valve - The relief valve maintains system oil pressure by use of a spring and piston. An adjustment screw compresses the spring which varies the pressure required to displace the piston and flow oil.

g. Thermometer - An alcohol filled stem-type thermometer is used to monitor system oil temperature.

h. Pressure Gauge - A glycerin filled bourdon tube type pressure gauge is used to monitor system oil pressure. An isolation valve is included so gauge maintenance can be done while the vessel is underway.

i. Low Oil Pressure Alarm Switch - This device is used to provide an alarm signal to the ship's bridge in case oflow oil pressure.

j. High Oil Temperature Switch - (Optional) This device is used to provide an alarm signal to the ship's bridge in case of high oil temperature.

k. Low Oil Level Switch - (Optional) This device warns of low oil level by using a magnet-equipped float and reed switch.

1. Thermostatic Bypass Valve - (Optional) In cold climates, this device is used to direct oil around the heat exchanger until it reaches a pre-set temperature. This is extremely important since very cold oil can become so thick that it will not flow properly through feeder passages. If engine room ambient temperatures are below 50°F, then a thermostatic bypass valve should be used.

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CAUTION

Operation using only splash lubrication should be limited to emergency situations and should be limited to half propeller speed. If speeds over half speed are used, care must be taken not to overheat the oil. If the oil pump is not working, oil will not be going through the heat exchanger, and the thermometer will not be useful in monitoring oil temperature.

The splash lubrication system insures the reduction gear will operate under emergency conditions without the benefit of the oil pump. This is accomplished by the low speed gear dipping in oil and scattering that oil inside the gear. This scattered oil lubricates the reverse gears and is collected in oil troughs as it runs back to the sump. These troughs direct the oil to each bearing.

3-7 CLUTCHES

Clutch engagement occurs when air pressure is applied to the clutch through the rotorseal.

The inflation rate of the clutch is controlled from 5 to 50 psi. Once the air pressure reaches 50 psi, the clutch is "locked up" and rapid inflation to 150 psi is desirable for quicker maneuvering response. All clutch slip occurs between 5 and 50 psi. The clutch disengages when air pressure is removed. Clutch exhaust must be rapid to eliminate clutch drag during disengageme,nt. A surprising quantity of heat can be generated at the clutch drum surface by sluggish disengagement, and will reduce the service life of the clutch.

The splash lubrication system insures the reduction gear will operate under emergency to overheat the oil. If the oil pump is not working, oil will not be going through the heat exchanger, and the thermometer will not be useful in monitoring oil temperature. This is accomplished by the low speed gear dipping in oil and scattering that oil inside the gear.

This scattered oil lubricates the reverse gears and is collected in oil troughs as it runs back to the sump. These troughs direct the oil to each bearing.

3-8 FLEXIBLE COUPLING

The main propulsion engine is connected to the marine gear via a Vulkan-Rato flexible coupling. The coupling is comprised of four flexible segments, a membrane, link, and various connecting parts. All connecting elements are joined with no clearance which eliminates wear. The free-of-play torque transmission and the large sectional rubber area provide good noise attenuation and heat dissipation.

3-8.1 Flexible Segment

The flexible segment consists of 4 pieces which are supplied as a set. The position of the segments toward each other are marked.

3-8.2 Membrane and Link

The membrane consists of a number of circular membranes, which are clamped into rubber cone bushings on their outer side. The link consists of flexible links which are arranged in tangential direction. The membrane and link respectively are arranged behind the flexible segments and provide axial displacement capacity.

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T9241-AM-MMO-0IO

CHAPTER4

SCHEDULED MAINTENANCE

4-1 INTRODUCTION

This chapter contains information on normal scheduled maintenance procedures pertaining to the Lufkin RS2719S Reverse Reduction Marine Gear. Detailed information for maintenance and repair or replacement is discussed in Chapter 6.

4-2 GENERAL

A properly installed and operated Marine Gear requires very linrited maintenance and/or repair. Scheduled Maintenance procedures include inspections, checking lubricant levels and cleaning/replacing filters.

The Scheduled Maintenance instructions in this manual are not intended to duplicate those furnished in the Planned Maintenance System (PMS). In case of conflicts, the PMS documentation takes precedence. Such conflicts should be reported immediately on the user activity technical manual comment sheet

4-3 MAINTENANCE PLAN

4-3.1 Daily Maintenance

Should consist of monitoring the lubricating oil pressure and temperature gauges.

4-3.2 Weekly Maintenance

Check oil level in sump (this check must be made while the unit is shut down). Check oil filter element for foreign material. Clean and/or replace filter element and reinstall if dirty.

The clutch linings should be inspected weekly and if a lining becomes badly saturated with oil, the friction shoes should be removed and cleaned or replaced. The inspection may be done by viewing the shoes through the ventilating holes in the clutch backplate. If cleaning is required, the friction shoes should be thoroughly cleaned with a safety cleaner suitable for use on oil.

4-3.3 Quarterly Maintenance

Take oil sample and submit for laboratory analysis. It is recommended that the oil be changed in the following cases:

a. The total acid number increases by 2. For example: new oil might have a total acid number of 0.5. When this number increases to 2.5 or above, the oil should be changed. This acid number increase is associated with oxidation of the oil which results in oil breakdown.

b. A decrease in the sulfur-phosphorus content is noted. These elements are "EP" (extreme pressure) additives and a reduction of these elements means the "EP" additive is breaking down.

c. The total solid content is more than 2%. This would indicate excessive dirt and/or

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1'9241-AM-MMO-010

wear particles.

d. A rapid change in viscosity is noted. Gear oil is "sheared" as it lubricates the meshing gear teeth. This "shearing" eventually causes the oil to thin out and lose its film thickness. A rapid increase could mean oxidation.

e. The water content is more than 2%. Water in oil causes the oil to lose its film strength and also will cause corrosion to gear elements and bearings.

f. The silicon content is above 50 parts per million. This signifies the oil is dirty.

g. The iron content is above 200 parts per million. This would indicate contamination from gear wear particles.

h. A rapid increase is noted in any of the wear elements.

As a guide, if rapid increases of any of the following wear elements are detected, the probable origins of that material are listed.

Brass or Bronze - Bearing roller cage, oil cooler.

Alloy Steel - Gear teeth, bearings.

Mild Steel - Oil pump, slinger, or baffle rubbing gear case.

Cast Iron - Bearing carrier, oil pump.

Aluminum - Oil seal, seal guards or carriers.

The greatest advantage to oil analysis is that it can detect many failures before they are catastrophic. The only way to do this is to take frequent samples and have them evaluated immediately, monitor the results; if a change is noted, respond accordingly.

4-3.4 Semi-Annual Maintenance

Inspect heat exchanger tubes for possible errosion, corrosion, or foreign material. Inspect zinc anodes to be sure they are not excessively corroded or insulated with scale. Scrape them to bright medal if scale is present. Replace if 50% erroded.

4-3.5 Annual Maintenance

Visually inspect flexible coupling and check alignment.

4-3.6 Gear Contact Check

Periodically check gear tooth contact to insure that the contact pattern is even across the face and that no abnormal wear is occurring. Heavy contact or pitting on one end of a helix that diminishes toward the opposite end of that helix could indicate a bad bearing, a worn bearing carrier, or a mis-aligned gear case.

Abnormal wear across the entire tooth could indicate contaminated oil or tooth overload.

Refer to Chapter 6 to aid in wear evaluation.

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Pay close attention to changes in the wear pattern of the gear teeth from one inspection to the next. A sudden change could be the forewarning of problems.

4-3.7 Oil Change

Under normal operating conditions, the lubricating oil should be changed every 2500 hours of operation or every six months whichever comes first The unit should be drained by removing the drain plugs located on the forward and aft side of the sump. After changing the oil filter, and cleaning the suction line strainer, refill the unit with new oil. (See chapter 1 for oil type.) Be sure that the correct oil level has been reached before starting again.

4-4 OIL PUMP MAINTENANCE

The oil pump requires no adjustment after it leaves the factory. It should not be disassembled as it is possible to rearrange the suction and discharge ports resulting in loss of oil circulation.

If for any reason the pump cover is removed, the small bulge in the cover should point to the suction side of the pump when reassembled.

4-5 CLUTCH INSPECTION

The Eaton-Fawick clutch/brake depends upon the gripping ability of high grade asbestos friction blocks against a finely finished drum. Foreign materials such as oil, grease, paint, water, etc., or solids which might embed into the friction blocks, and cause abnormal drum wear will greatly reduce the clutch/brake gripping capacity and may result in clutch/brake slip, heat build up and loss of power to the ship's propeller. Therefore, the clutch/brake must be kept clean of any foreign material and should be inspected at regnlar intervals for such foreign material. If contaminants do get into the clutch/brake, they must be removed even though a major disassembly might be required. Inspectors should look for:

1. Foreign material

2. Friction block wear

3. Airleaks

4. Broken parts

5. Loose bolts and capscrews

6. Looseness between hub and shaft

4-6 RECOMMENDED PRACTICE FOR PRESERVING GEAR

TEETH & BEARINGS DURING INOPERATIVE PERIODS

Most reco=ended operating oils will protect exposed surfaces from corrosion for inoperative periods up to 30 days.

If additional down time is needed, the customer should spin the unit every 30 days to redistribute the oil to the non-submerged parts and gain another 30 days protection.

If extended down time is expected and it is impractical to spin the unit, a rust preventive type oil should be brushed or sprayed on the gear teeth and bearings. Any openings such as breathers or labyrinth seals should be sealed. A quality rust preventive oil should give 12 months protection against corrosion. This oil should be compatible with the operating oil, and it should be unnecessary to remove the rust preventive oil when the unit is started again.

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CHAPTERS

TROUBLESHOOTING

5-1 INTRODUCTION

This chapter discusses common Marine Reduction Gear problems and provides guidance in determining their causes and suggests methods of correction.

CAUTION

Marine Reduction Gears are precision made to extremely close tolerance. Operating the gear under casualty conditions may cause extensive equipment damage. It is recommended that the gear be stopped whenever unusual noise, vibration, or loss of lubricating oil is detected, and the cause be determined and corrected before restarting.

5-2 TROUBLESHOOTING

The following are common Marine Gear problems, probable causes and suggested methods of correction.

5-2.1 Abnormally High Oil Temperature

High oil temperature can be caused by an inadequate water flow through the heat exchanger, or by cooling water that is too hot. Check the technical data sheet in Chapter 1, for water flow and temperature.

If the oil level in the gear box is so high that the gear runs too deeply in the oil, then the resulting churning action will heat up the oil. Check the oil level with the dip stick and remove oil if necessary.

If the gear housing should get coated with a foreign material that will not permit natural heat removal by convection, high temperature may result. To prevent this, the unit should be cleaned periodically.

Obviously, a high ambient temperature will cause abnormally high temperature. To prevent this, allow for adequate ventilation around the gear.

If the oil flow to the bearings and gear mesh is below normal (indicated by below normal oil pressure), the heat created by friction at the mesh and bearings will cause abnormally high temperatures. To correct this situation, check the lubrication system (see 5-2.2 below) for the problem. Maintaining proper oil flow will carry heat to the heat exchanger where excess heat will be removed from the system. ·

Coupling misalignment can cause high operating temperature by introducing unnecessary friction to the gear box. This may be corrected by maintaining proper coupling alignment.

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5-2.2 Low Oil Pressure

One possible cause of low oil pressure is the use of a lubricant which has a viscosity less than that for which the lube system was designed. There are several orifices in the lube system which are sized for lubricants with a particular viscosity. A lubricant with less than normal viscosity will pass through the orifices without building up pressure. This situation can be prevented by using the lubricant designated on the name plate of the gear unit Abnormally low viscosity may also result from high lubricant temperatures. (See 5-2.1 on abnormally high temperatures)

A clogged oil filter will also cause low oil pressure. Replacing the filter will allow more ·oil to flow through it, thus bringing the oil pressure back to normal.

Another cause of low oil pressure is pump cavitation. Should the oil level in the sump get so low that the pump suction line sucks both air and oil, then the oil pressure will drop off. This problem may be cured by maintaining proper oil level in the sump.

Another cause of low oil pressure is an air leak in the suction line to the pump. This situation is similar to pump cavitation in that air gets in the oil and results in low oil pressure. To remedy this problem, check and tighten all pipe fittings in the suction line.

An incorrect relief valve setting may also cause low oil pressure by venting the pump discharge line back to the sump before proper pressure is built up. The relief valve may be reset by adjusting the spring adjusting screw under the cap.

5-2.3 Unusual Noise

One common cause of unusual noise is worn parts. If a part wears enough to cause slack in the system, the slack may be heard as a rattle or noise of some sort. A mechanic's stethoscope may be used to pinpoint the worn part which should be replaced.

An input coupling that is out of alignment may also cause noisy operation. The misaligned coupling causes misalignment in the gear train which produces noise or vibrations. The coupling should be immediately realigned before damaging wear occurs.

5-2.4 Excessive Vibrations

Loose foundation bolts may cause the gear unit to vibrate. This may be prevented by checking the tightness of the bolts periodically.

Any unbalanced rotating parts may also cause excessive vibrations. In this case, the amplitude and frequency of vibration is directly proportional to the rotational speed of the unbalanced part. In checking for unbalanced parts, make certain that full length half-keys are used in all exposed keyways, and that the correct type of coupling is used.

A foundation that is not sufficiently rigid may also cause vibration problems. To correct this, reinforce the foundation. ·

At certain speeds a rotating shaft will become dynamically unstable, and the resulting vibrations and deflections that occur may cause damage to the gear unit The speeds at which the shaft becomes unstable are called the critical speeds. They are a function of the shaft geometry and the type and spacing of the supporting bearings.

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Torsional vibrations may be caused by operating the gear unit with an engine/propeller shaft system that is not torsionally compatible; that is a system in which the inherent torsional vibrations do not dampen out, but build to damaging proportions.

5-2.5 Clutch Troubleshooting

The following table gives clutch malfunction symptoms, probable cause, and suggested corrections.

Table 5-1 Clutch Troubleshooting

MALFUNCTION CAUSE SOLUTION

SYMPTOM

Excessive slip, detected by A. Low air pressure A. Increase to 105 PSI loss of power, high min.

clutch/brake smoke

B. Foreign material in friction surface

B. Clean completely

C. Worn friction blocks C. Replace when worn to min. thickness

Slow engagement or A. Blocked air line A. Clean or replace disengagement

B. Sticking quick release B. Replace valves or 4-way valve

C. Embedment of foreign C. Clean or replace material in friction shoe

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CHAPTER6

6-1 INTRODUCTION

This chapter provides information and instructions on the disassembly, inspection and reassembly of the Lufkin RS2719S Reverse Reduction Marine Gear. Instructions are also given for the repair/replacement of the oil pump and clutches.

NOTE

Repair/Replacement of any internal gears or bearings should be accomplished only under the supervision of Lufkin or other qualified engineers experienced in marine gear repair.

6-2 GEAR DISASSEMBLY

II WARNING u Care should be taken to insure that the main or auxiliary propulsion engines do not turn the gear unit while maintenance is underway on the gear as personal injury or loss of life could occur.

n WARNING U Care should be taken…