7241 MARINE TRANSMISSION Caterpillar

Top Shaft

Usage:

Top Shaft Removal

The following disassembly and assembly illustrations were taken on a marine gear separated from the engine. It is not necessary to disconnect the marine gear from the engine for disassembly.

1. Remove top housing cover (1) from the main housing.

2. Disconnect oil hose (2) from the control valve.

3. Remove oil filter assembly (3).

MARINE GEAR--LEFT REAR VIEW
1. Top housing cover. 2. Oil hose. 3. Oil filter assembly. 4. Oil pump. 5. Manifold and control valve.

4. Remove oil pump (4) from manifold (5).

NOTE: For oil pump drive sleeve replacement, see SPECIAL INSTRUCTION FORM SMHS7721.

5. Remove oil manifold and control valve (5) as a unit.

COVER REMOVED FROM HOUSING
6. Bearing caps. 7. Top halves of bearing rear retainers. 8. Oil tubes.

6. Remove oil tubes (8).

7. Remove the top halves of the bearing rear retainers (7).

8. Place blocks under the clutch drive and remove the bearing caps (6).

BEARING CAPS REMOVED FROM HOUSING
9. Tapped hole in clutch cylinder. 10. Top shaft. 11. Lower halves of bearing rear retainers.

9. Loosen the bolts in bearing rear retainers (11).

10. Install an eyebolt in the tapped hole (9) in the clutch cylinder.

11. With a rope or nylon sling placed around the rear of top shaft (10), lift the complete clutch and top shaft assembly from the housing.

NOTE: If the marine gear is connected to the engine, follow Steps 1 through 7. Match mark the location of marine gear drive (13) on the flywheel as illustrated with marks (12). Remove the six marine gear drive retaining bolts and locks and separate drive (13) from the flywheel. Continue the removal by following Steps 8 through 11.

REMOVING TOP SHAFT ASSEMBLY

MARINE GEAR DRIVE
12. Location marks (drive to flywheel). 13. Marine gear drive.

REMOVING TOP SHAFT ASSEMBLY

Top Shaft Installation

The ahead gear shaft can move into the clutch assembly if the pump drive end of the top shaft is lifted higher than the clutch assembly. Blocks or jacks placed between the ahead gear and the clutch assembly rear plate will prevent ahead shaft movement when lifting the top shaft.

When the top shaft is being installed, tighten bearing cap bolts (6) only enough to seat the bearings. Tighten the bolts through bearing rear retainers (7 and 11) and then finish tightening the bearing cap bolts.

Thoroughly clean and dry the mounting surfaces of the oil manifold-to-main housing and the oil pump-to-oil manifold. Use 7M7260 Gasket Material on the clean dry surfaces when installing oil manifold (5) and pump (4). Install new O-ring seals on the pump inlet and outlet tubes.

Make certain the piston ring-type seals are not broken when oil manifold (5) is installed.

Connect oil hose (2) to the control valve and install filter assembly (3).

Make certain the gasket is in satisfactory condition when installing top housing cover (1).

Top Shaft Disassembly and Assembly

1P2420 Transmission Repair Stand.FT957 Vertical Legs (four).FT996 Positioning Group.FT989 Retaining Bracket (two).FT841 Piston Spring Clamping Tool.3S6224 Electric Hydraulic Puller or9S5800 Pump Group.5H9817 Hydraulic Puller.1H3107 Push Puller.1H3109 Leg (two).1H3110 Bearing Pulling Attachment.5F7343 Bearing Pulling Attachment.8B7561 Step Plate.1P2321 Puller Assembly.1P1855 External Retaining Ring Pliers.1P516 Plate from the 1P520 Drive Set.

FT957 VERTICAL LEGS & FT996 POSITIONING GROUP
Dimensions in inches (mm)

FT989 RETAINING BRACKET
Dimensions in inches (mm)

FT841 PISTON SPRING CLAMPING TOOL
Dimensions in inches (mm)

Clutch Disassembly

Carefully remove the six piston ring-type seals from the oil pump drive end and place the top shaft assembly on four FT996 Positioning Group with four FT957 Legs (3), on 1P2420 Transmission Repair Stand (6). Attach at least two legs (3) to clutch plate assembly (4).

TOP SHAFT ASSEMBLY ON STAND
1. Bolts (four). 2. Nuts (twelve). 3. FT957 Legs. 4. Clutch plate assembly. 5. Retaining brackets. 6. 1P2420 Transmission Repair Stand.

1. Install two FT989 Retaining Brackets (5), with bolts, to clutch plate assembly (4).

2. Remove four bolts (1) and the two locks from the astern clutch shaft bearing retainer.

3. Remove twelve nuts (2) and the six locks, which retain the spider clutch drive, and remove the spider and oil pump drive shaft from the clutch assembly.

4. Remove astern clutch discs and plates (7).

REMOVING SPIDER AND PUMP DRIVE SHAFT

ASTERN CLUTCH DISCS AND PLATES
7. Disc assemblies (five) and plates (four). 8. Cylinder assembly.

5. Remove cylinder assembly (8).

6. Remove ahead clutch discs and plates (9).

7. Place support blocks under the pump drive end of the shaft and carefully remove two retaining brackets (5). Remove clutch plate assembly (4).

8. The astern and ahead clutch dump valves and plungers are identical. If a dump valve is removed from clutch cylinder (8), the plunger (10) will slip out of the valve body.

REMOVING CLUTCH CYLINDER

AHEAD CLUTCH DISCS AND PLATES
4. Clutch plate assembly. 9. Disc assemblies (five) and plates (four).

9. Remove clutch pistons (12 and 13) from clutch cylinder (8) by compressing the piston return springs with FT841 Clamping Tool, then remove the spring retaining rings with 1P1853 Ring Pliers.

DUMP VALVE
10. Plunger.

PISTON RETURN SPRING REMOVAL
11. Retainer ring. 12. Ahead clutch piston. 13. Astern clutch piston.

CLUTCH CYLINDER AND PISTON

10. To remove oil pump drive shaft (14) from the spider, remove four bolts and locks (16). Use two bolts, in the threaded holes in cover (15), to separate the cover and shaft from the spider. Cover (15) is pinned to shaft (14). The internal splined oil pump drive, in the other end of shaft (14), is also secured with a pin.

DRIVE SHAFT REMOVAL
14. Oil pump drive shaft. 15. Cover. 16. Bolts (four). 17. Clutch drive blocks (thirty-six).

11. To remove astern clutch shaft bearing (18), remove bolts, locks and bearing retainer (19) from the spider and use 1P2321 Puller Assembly and a suitable step plate.

ASTERN CLUTCH SHAFT BEARING REMOVAL
18. Bearing. 19. Bolts, locks and bearing retainer.

Clutch Assembly

1. Heat bearing (18) in oil not to exceed 240° F (115° C) to facilitate bearing installation. The shield face of the bearing is toward the oil pump drive end of the shaft.

2. If the gasket between cover (15) and the spider was damaged, when the cover was separated from the spider, install a new gasket when cover (15) and shaft (14) are installed in the spider.

3. When assembling ahead clutch piston (12) and astern clutch piston (13) in cylinder assembly (8), use the FT841 Spring Clamping Tool to compress the piston return washer and spring. 1P1855 Retaining Ring Pliers are used when installing the piston return spring retainers.

4. Place clutch plate assembly (4) over the shaft and install the two FT989 Retaining Brackets (5).

5. If the overall height of five disc assemblies and four plates (9), alternately stacked, is near the minimum permissible worn dimension of 2.208 in. (56.08 mm), install new disc assemblies. Make certain the surfaces of the plates are not rough.

6. Install cylinder assembly (8) and disc assemblies and plates (7), if the stacked height of five discs and four plates (7), alternately stacked, is near the minimum permissible worn dimension of 2.208 in. (56.08 mm), install new disc assemblies.

7. Install the astern clutch ring over the discs and plates, the clutch drive spider and pump drive shaft.

8. Remove FT989 Retaining Brackets (5).

NOTE: To prevent the ahead shaft from moving into the clutch assembly, before the top shaft is installed in the marine gear housing, place blocks or jacks between the ahead gear and clutch plate assembly (4).

9. Carefully install the six piston ring-type seals on the end of the shaft.

Astern Clutch Shaft and Ahead Clutch Shaft Disassembly

Remove the top shaft from the marine gear housing and remove the clutch assemblies.

1. Place the clutch end of astern clutch shaft (1) on blocks and remove bearing retaining nut (2) and lock (4).

ASTERN CLUTCH SHAFT BEARINGS
1. Astern clutch shaft. 2. Retainer nut. 3. Bearing assembly (one bearing cup removed). 4. Lock.

2. Remove bearing assembly (3) by using the 5F7343 Bearing Pulling Attachment, two 1H3109 Legs, 1H3107 Push Puller, a suitable step plate, 5H9817 Hydraulic Puller and either the 3S6624 Electric Hydraulic Pump or the 9S5800 Pump Group.

REMOVING BEARING ASSEMBLY

3. Remove the spacer resting on gear (5). Remove gear (5) from astern clutch shaft (1). The tools necessary for removing gear (5) are the same tools used to remove bearing assembly (3) except use the 1H3110 Bearing Pulling Attachment in place of the 5F7343.

4. After gear (5) is removed, remove the gear key from the shaft. Lift the ahead clutch shaft (8) off of the astern clutch shaft (1) and place it on blocks.

5. Remove the retainer nut, lock and spacer from shaft (8).

GEAR REMOVAL
5. Gear.

6. Remove the bearing assembly (6), the spacer under the bearing and gear (7) from shaft (8) at the same time. Use the same tools which were necessary to remove gear (5) with the addition of 1P516 Plate between the hydraulic puller and the shaft.

GEAR AND BEARING REMOVAL
1. Astern clutch shaft. 6. Bearing assembly. 7. Gear. 8. Ahead clutch shaft.

REMOVING BEARING
9. Bearing.

7. Remove the gear key from shaft (8). Remove bearing (9) with the same tools used to remove bearing (6) and gear (7).

8. If either bearing (10) or bearing (11) is damaged, it may be necessary to destroy the damaged bearing to remove it from the ahead clutch shaft (8).

AHEAD CLUTCH SHAFT
10. Bearing. 11. Bearing.

Astern Clutch Shaft and Ahead Clutch Shaft Assembly

The diameters of the shafts and the bores in the bearings and gears will not allow either the bearings or the gears to be assembled on the shafts incorrectly.

Each bearing assembly includes two roller bearing cones, two bearing cups and a spacer between the cups. The bearings are marked to make certain a cone and the corresponding numbered cup will be installed together. The large diameters of the roller bearing cones are installed back to back, this makes it necessary to place bearing cup on the shaft before the first roller bearing cone is installed.

AHEAD CLUTCH SHAFT

1. Race.

2. Shield.

3. Race.

4. Bearing assembly.

5. Cup.

6. Cones.

7. Cup.

8. Spacer.

9. Shaft assembly.

10. Key.

11. Gear.

12. Spacer.

13. Cup spacer.

14. Lock.

15. Nut.

Take care when assembling the shafts because the bearing assembly cups and spacers, the gear keys and the spacer between each gear and bearing assembly can be easily overlooked when installing the heated gears and bearings.

1. Install shield (2) in shaft assembly (9).

2. Freeze race (1) and install it in shaft assembly (9).

3. Heat race (3), bearing assembly (4), gear (11) and bearing cones (6) in hot oil to a temperature of 350° F (176° C).

4. Install race (3) and bearing assembly (4).

5. Install key (10) and gear (11).

6. Install spacer (12), cup (5) and cones (6).

7. Allow the assembled parts to cool for four hours.

8. Install the 7H7539 Nut and 4K684 Washer (16), FT1506 Plate (17), (with the step on the plate toward the shaft), FT1508 Spacer (18), (with the counterbore toward the bearings), 5P2998 Hydraulic Puller (19), 4K684 Washer and 3K9770 Nut (20) and 9S5558 Stud (21) apply a force of 16.5 ± 2.5 ton (148 ± 22 kN) force to seat the bearings and gear.

9. Remove the tools and install cup (7), spacer (8) and lock (14).

10. Put 5P3931 Anti-Seize Compound on threads of nut (15) and install the nut.

11. Use the 6V3132 Spanner Wrench and 6V3134 to tighten nut (15) to a torque of 500 lb. ft. (680 N·m).

12. Bend one of the tabs on lock (14) into one of the slots in nut (15).

AHEAD CLUTCH SHAFT ASSEMBLY