Usage:
Lubrication System
1 Oil pump.
2 Manifold.
3 Selector valve.
4 Passage.
5 Ahead clutch shaft rear support bearing assembly.
6 Passage.
7 Cavity.
8 Passage.
9 Ahead clutch.
10 Astern clutch.
11 Passage.
12 Front spider bearing.
13 Rear spider bearing.
14 Astern clutch shaft rear support bearing assembly.
15 Oil tube.
16 Astern clutch shaft front support bearing.
17 Ahead clutch shaft front support bearing.
18 Passage.
19 Output bearing assembly.
20 Planet gear bearing.
21 Lower shaft rear support bearing.
22 Lower shaft front support bearing assembly.
LUBRICATING OIL FLOW (Section View)
The gear-type oil pump (1), located at the rear of the marine gear, is splined to a shaft which is splined to the drive spider. The volume of oil which the oil pump delivers depends on the speed of the engine. Oil is drawn from the sump through a metallic strainer, to the pump and then to the filter, selector valve and oil cooler. These components are connected by a series of flexible hoses and steel tubes.
Oil to lubricate and cool the clutch plates (9) and (10) is pumped directly through the manifold (2) to the passage (4) between the oil pump drive shaft and the astern clutch shaft. This passage permits the oil to reach the passage (8) leading to the ahead clutch plates and the passage (11) leading to the astern clutch plates. Grooves in the sintered bronze driven clutch plates channel the oil between the driving and driven plates in an outward direction. Centrifugal force throws the oil off the clutch circumference and the oil then returns to the sump. The bearings (12), (13), (14) and (16) are lubricated by oil routed to the clutches.
Catch basins above the bearings (5) and (22) channel lubricating oil into the notched bearing spacers. The straight roller bearings (17) and (21) are splash lubricated. Oil from the manifold is routed from the cavity behind bearing (14), through the oil tube (15), to the output bearing (19). The passage (18), through the spacer of this bearing, channels oil through the carrier radially to the three planet gear bearings (20).
NOTE: Regardless of the position of the selector valve lever, an ample supply of oil is supplied through the manifold to lubricate the bearings and gears. The clutches are always lubricated and cooled in any selector valve position.
| NOTICE |
|---|
When the vessel is being towed with the engine stopped, the propeller shaft should be disconnected from the marine gear or the propeller rotation prevented in some suitable manner. The oil pump would not operate under these conditions and serious damage to the bearings, gears and clutches would result. |
By-pass System
The oil filter by-pass valve allows lubrication and cooling of the marine gear regardless of any possible stoppage of the normal flow passages because of either cold oil or a clogged filter.
The normal oil flow is from the pump to the oil filter to the selector valve. By-pass oil from the selector valve is directed from the selector valve to the oil cooler and back to the manifold. Should the oil filter be restricted, the filter by-pass valve opens, allowing oil to go directly to the selector valve from the pump. This, however, is an emergency type of operation and should not be allowed to continue any longer than necessary before replacing the filter.
Hydraulic System
Actuating Oil to Clutches
ACTUATING OIL TO AHEAD CLUTCH (Cross Section)
1-Manifold. 2-Selector valve. 3-Passage. 4-Clutch spider. 5-Passage. 6-Clutch cylinder. 7-Passage through driving ring. 8-Cavity. 9-Ahead clutch plates. 10-Ahead clutch piston. 11-Dump piston.
When the selector valve (2) is moved to engage the ahead drive clutch plates (9), high pressure oil flows from the manifold (1) through the passage (3) around the tube in the center of the oil pump drive shaft.
A passage (5) in the clutch drive spider (4) intercepts and carries the oil outward where it is directed through the passage (7) in the clutch drive ring and into the clutch cylinder (6). As high pressure oil enters the clutch cylinder it moves the dump valve piston (11) toward the center of the cylinder where it blocks the dump valve exit (13). As the high pressure oil enters the cylinder cavity (8) behind the ahead clutch piston (10), the piston moves the clutch plates together and engages them. See the illustration for oil flow through the dump valve.
HIGH PRESSURE OIL FLOW THROUGH DUMP VALVE (Dump Valve Cutaway)
11-Dump valve piston. 12-High pressure oil entrance. 13-Dump valve exit. 14-Passage to clutch cavity.
Disengagement of the clutch occurs when engaging oil pressure is cut off from the dump valve piston by the selector valve. The dump valve piston, unrestrained by engaging oil pressure, is moved outward by centrifugal force, aligning the dump passage (15) through the piston with the passage to the clutch cavity (14). Oil which was in the clutch cavity now moves out of the cavity by centrifugal force and passes through the dump valve piston to the dump valve exit (13) and then to the sump. See the illustration.
DUMP OIL FLOW THROUGH DUMP VALVE (Dump Valve Cutaway)
11-Dump valve piston. 13-Dump valve exit. 15-Dump passage through piston from clutch cavity.
When the selector valve (2) is moved to engage the astern clutch plates (20), high pressure oil flows from the manifold through the passage (17) in the center of the tube running through the oil pump drive shaft. The oil flows to the fore end of the oil pump drive shaft and through a passage (16) in the retainer cover. Oil is routed back into the hub of the clutch spider (4) by the passage (16). From the hub, oil flows outward into passage (18), which is located 180° from the ahead clutch passage (21) and moves the astern clutch dump valve (22) through the clutch drive ring through the passage (21) and moves the astern clutch dump valve piston (23) inward blocking the dump exit. The astern clutch dump valve is located 180° from the ahead clutch dump valve. As the high pressure oil enters the cavity (24) behind the astern clutch piston (19), the piston forces the astern clutch plates (20) together. Power is then transmitted from the flywheel through the astern clutch and power train.
1 Manifold.
2 Selector valve.
4 Clutch spider.
16 Passage.
17 Passage.
18 Passage.
19 Astern clutch piston.
20 Astern clutch plate.
21 Passage.
22 Cylinder.
23 Dump valve piston.
24 Cavity.
ACTUATING OIL TO ASTERN CLUTCH
Operation
Power is transmitted from the engine through the clutches to the clutch shafts (2) and (4). Power from the engine is transmitted through the drive ring (6) which is secured to the engine flywheel and mated with the drive spider (7). The drive spider is secured to the clutch drive rings (5) by studs. The clutch drive rings mate with teeth on the circumference of the steel clutch driving plates (9). Teeth on the inner diameter of the sintered bronze clutch driven plates (10) mate with teeth on the shafts (2) and (4).
1 Idler gear.
2 Astern clutch shaft.
3 Astern drive gear.
4 Ahead clutch shaft.
5 Clutch drive rings.
6 Drive ring.
7 Clutch drive spider.
8 Coupling flange.
9 Steel driving plate.
10 Sintered bronze driven plates.
11 Ahead drive gear.
12 Lower shaft.
13 Carrier.
14 Planet gear.
15 Astern driven gear.
16 Sun gear.
17 Ahead driven gear.
18 Sun gear shaft.
MARINE GEAR OPERATION
The clutches are hydraulically actuated by positioning the selector valve lever in the appropriate clutch drive positions. When the selector valve lever is placed in the ahead clutch engaged position, the power is transmitted from the clutch spider (7) and drive rings (5) through the steel clutch drive plates of the ahead clutch (19) to the sintered bronze driven plates. Teeth on the inside diameter of these driven plates transmit the power to the ahead clutch shaft (4). The power is transmitted from the ahead clutch shaft to the lower shaft (12) by two constant mesh helical gears (11) and (17). The gears change the direction only and do not change the lower shaft speed. The ahead driven gear (17) is keyed to the lower shaft (12) which is internally splined to the sun gear shaft (18). Power is transmitted from the sun gear to the carrier (13) by the three planet gears (14). The coupling flange (8) is splined to the planet carrier and transmits power to the propeller shaft through the companion flange. Reduction in speed takes place in the planetary system only.
AHEAD CLUTCH DRIVE SCHEMATIC (Right Hand Propeller)
19-Ahead clutch.
When the selector valve lever is placed in the astern clutch (20) engaged position, power is transmitted from the clutch drive spider (7) and drive ring (5) to the astern clutch steel drive plates. The sintered bronze driven plates transmit power to the astern clutch drive shaft (2) and astern drive gear (3) which is in constant mesh with the idler gear (1). Power is then transmitted from the idler gear to the astern driven gear (15). The astern driven gear is keyed to the lower shaft as was the ahead driven gear. Power is transmitted to the propeller shaft from the lower shaft (12) in the same manner as described for the ahead drive. The idler gear provides means for opposite rotation in the astern power train.
ASTERN CLUTCH DRIVE SCHEMATIC (Right Hand Propeller)
20-Astern clutch.
Since the gears in the power transmission are in constant mesh, the disengaged clutch will turn in the direction opposite to that of the engaged clutch.
For the hydraulic operation of the clutches, see the topic HYDRAULIC SYSTEM.