Motor 3304 Inyeccion Directa - Scroll Fuel System

FORM NO. SENR2253-01 FOR USE IN SERVICE MANUALS: 950B WHEEL LOADER, SENR2249 215 EXCAVATOR, SENR7421 225 EXCAVATOR, REG01578 518 SKIDDER, REG00971 120G MOTOR GRADER, REG01654 130 & 140G MOTOR GRADERS, REG01652

SYSTEMS OPERATION TESTING AND ADJUSTING

3304 DIRECT INJECTION VEHICULAR ENGINE WITH NEW SCROLL FUEL SYSTEM 7Z 9Z 12Z

3304 DIRECT INJECTION VEHICULAR ENGINE WITH NEW SCROLL FUEL SYSTEM

INDEX

SYSTEMS OPERATION Air Inlet and Exhaust System Head, Cylinder.. .. .. System, Air Inlet and Exhaust Turbocharger. . . . . . . . . . . . . . . . . . . . ............. .. Valves , .. . . .. .. Valve Mechanism.....................................

15 14 14 15 15

Basic Block Block, Cylinder.. . . . .. .. .. .. .. .. .. .. .. .. . . .. . . . . . . Crankshaft ,.. Pistons................ .. Rings, Piston Rod, Connecting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

20 20 20 20 20

Cooling System Coolant Flow...... .. .. Cooling System Components. . . . .

18 19

.. .. . . . . . . . . . .

Electrical System Charging System Components Other Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Starting System Components. . . . . . . .. . . . . . . . . . . . . .. Engine Design. . . . . . . . . . . . . . . .. . . . . . . . . . .. ... . .. .. . . .

21 22 21 4

Fuel System Control, Air Fuel Ratio.. . .. . .. Fuel Flow............................................. Governor............................................. Nozzle, Fuel Injection. . . . . . . . . . . . . . . . . . . . .. . . ...... Oil Flow for Fuel Pump and Governor.. .. .. Pump. Fuel Injection.................. . . . . . . . . . . . . . . . . Pump, Fuel Transfer

12 5 9 6 8 5 7

Lubrication System System Oil Flow

16

TESTING AND ADJUSTING

Air Inlet and Exhaust System Air Inlet and EXhaust, Measurement of Restriction. . . . .. Camshaft Lobes, Measurement Procedure. . .. .. .. . . . . .. Exhaust Temperature, Measu rement of. . . . . . . . .. .... . .. Head, Cylinder. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Inlet Manifold Pressure, Measurement of .. .. .. .. Pressure, Crankcase (Crankshaft Compartment) . . . . . . .. Valve Clearance

58 60 58 59 58 59 59

Basic Block Bearings, Connecting Rod. . . . . . . . . . . .. . . .. .. . . . . . . . . .. Bearings, Main. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .. Block, Cylinder...... .. Flywheel Gauge, Piston Ring Groove , Housing, FlyWheel Pistons Rod, Connecting. . . . . . . . .. . . . . . . . . . . .. . . . . . . . . ..

66 66 67 67 66 67 66 66

Cooling System Chart, V-Belt Tension. Cooling System, Leak Test , Cooling System, Test Tools... .. Cooling System, Testing................ . ... Cooling System. Visual Inspection................... .. Pressure Cap, Testing.. Radiator, Leak Testing......... . .. .. .. Regulator, Water Temperature. . . . . . . . . . .. . . . . . . . . Relief Valve, Testing Thermostat. . . . . . . . . . . . . .. . .. . . . . . . . . . . . . . . . . ..

65 64 63 63 63 64 64 65 64 65

Electrical System Battery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Charging System Starting System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

71 71 72

Fuel System Control, Air Fuel Ratio; Governor Adjustment Cylinders, Engine; Checking Separately. . . . . . . . . . . . Engine Speed Measurement. . . . . . . . . . . . . . . . . . . . . .. Fuel Injection Pumps, Removal and Installation of Fuel Setting Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . .. .. .. Governor, Adjustments. . . ... . .. .. ... . . . . . . . . . . . . . . . . .. Inspection, Fuel System. . . . . . . . . . . .. . . . . . . . . . . . . . .. Lines, Fuel Injection Nozzles, Fuel Injection; Testing , Pump, Injection; Plunger and Lifter Check Timing Check, 6V31 00 Engine Timing Indicator Group.. Timing Check, Timing Pin Method. . . . . . ... . . . . . . . . . . .. Top Center Compression Position for No.1 Piston .....

46 35 54 40 49 55 35 40 36 40 43 44 42

Lubrication System Bearing Wear............. .. .. .. .. Oil Consumption , .. .. . . . . . . . . . . .. Oil Pressure, High Oil Pressure, Low.. .. . .. . . . . . . . . . . .. . . .. .. .. . . . .. ..

62 61 62 61

Troubleshooting. . . . . . . . . . .. . . . . . ... . . . . . . . . . . . . . . . . .. ..

23

3

ENGINE DESIGN

Bore Stroke Number of Cylinders Cylinder Arrangement Firing Order (Injection Sequence) Direction of Rotation (when seen from flywheel end) *No. 1 Cylinder is Opposite Flywheel End.

120.7 mm (4.75 in.) 152.4 mm (6.00 in.) 4 *in-line

1,3,4,2

'-'

Counterclockwise

EXHAUST VALVES

1

2

1 A76353X 1

3

2

4

3

4

INTAKE VALVES

CYLINDER AND VALVE IDENTIFICATION

---

4

SYSTEMS OPERATION

FUEL SYSTEM

FUEL SYSTEM FUEL FLOW

2

5

3

6

---­ 1 lL.: ~ ~~JJ B38442-2Xl

9

8

10

11

12

FUEL SYSTEM SCHEMATIC 1. Fuel tank. 2. Fuel return line. 3. Priming pump. 4. Fuel injection nozzle. 5. Fuel injection line. 6. Fuel injection pump. 7. Primary tuellilter. 8. Check valve. 9. Fuel transler pump. 10. Secondary fuel filter. 11. Constant bleed orifice. 12. Fuel injection pump housing.

Fuel is pulled from fuel tank (1) through primary fuel filter (7) and check valves (8) by fuel transfer pump (9). From the fuel transfer pump the fuel is pushed through secondary fuel filter (10) and to the fuel manifold in fuel injection pump housing (12). The pumping spring in the fuel transfer pump keeps the fuel pressure in the system at 170 to 290 kPa (25 to 42 psi). Constan't bleed orifice (11) lets a constant flow of fuel go thorugh fuel return line (2) back to fuel tank (1). This helps keep the fuel cool and free of air. Fuel injection pump (6) gets fuel from the fuel manifold and pushes fuel at very high pressure through fuel line (5) to fuel injection nozzle (4). The fuel injection nozzle has very small holes in the tip that change the flow of fuel to a very fine spray that gives good fuel combustion in the cylinder.

FUEL INJECTION PUMP The fuel injection pump increases the pressure of the fuel and sends an exact amount of fuel to the fuel injection nozzle. There is one fuel injection pump for each cylinder in the engine. The fuel injection pump is moved by cam (14) of the fuel pump camshaft. When the camshaft turns, the cam raises lifter (11) and pump plunger (6) to the top of the stroke. The pump plunger always makes a full stroke. As the camshaft turns farther. spring (8) returns the pump plunger and lifter to the bottom of the stroke.

5 ."

FUEL SYSTEM

SYSTEMS OPERATION

When the pump plunger is at the bottom of the stroke, fuel at transfer pump pressure goes into inlet passage (2), around pump barrel (4) and to bypass closed port (5). Fuel fills the area above the pump plunger. After the pump plunger begins the up stroke, fuel will be pushed out the bypass closed port until the top of the pump plunger closes the port. As the pump plunger travels farther up, the pressure of the fuel increases. At approximately 690 kPa (100 psi). check valve ( I) opens and lets fuel flow into the fuel injection line to the fuel injection nozzle. When the pump plunger travels farther up, scroll (9) uncovers spill port (10). The fuel above the pump plunger goes through slot (7), along the edge of scroll (9) and out spill port (10) back to fuel manifold (3). This is the end of the injection stroke. The pump plunger can have more travel up, but no more fuel will be sent to the fuel injection nozzle. 2

.M 4

3

I ..~

6

scroll (9) changes the distance the pump plunger pushes fuel between bypass closed port (5) and spill port (10) opening. The longer the distance from the top of the pump plunger to the point where scroll (9) uncovers spill port (10), the more fuel will be injected. To stop the engine, the pump plunger is rotated so that slot (7) on the pump plunger is in line with spill port (10). The fuel will now go out the spill port and not to the injection nozzle.

FUEL INJECTION NOZZLE The fuel injection nozzle goes through the cylinder head into the combustion chamber. The fuel injec­ tion pump sends fuel with high pressure to the fuel injection nozzle where the fuel is made into a fine spray for good combustion.

1\ F I

6

7

8 FUEL INJECTION

8

9

ID 12

13 A92938X1

FUEL INJECTION PUMP 1. Check valve. 2. Inlet passage. 3. Fuel manifold. 4. Pump barrel. 5. Bypass closed port. 6. Pump plunger. 7. Siol. 8. Spring. 9. Scroll. 10. Spill port. 11. Ufter. 12. Fuel rack. 13. Gear. 14. Cam.

When the pump plunger travels down and un­ covers bypass closed port (5), fuel begins to fill the area above the pump plunger again, and the pump is ready to begin another stroke. The amount of fuel the injection pump sends to the injection nozzle is changed by the rotation of the pump plunger. Gear (13) is attached to the pump plunger and is in mesh with fuel rack (12). The governor moves the fuel rack according to the fuel needs of the engine. When the governor moves the fuel rack, and the fuel rack turns the pump plunger,

6

5

B9219X1 ~OZZLE

1. Carbon dam. 2. Seal. 3. Spring. 4. Filler screen. 5. Inlet passage. 6. Orifice. 7. Valve. 8. Diameter. 9. Passage.

Seal (2) goes against the cylinder head and pre­ vents leakage of compression from the cylinder. Car­ bon dam (I) keeps carbon out of the bore in the cylinder head for the nozzle. Fuel with high pressure from the fuel injection pump goes into inlet passage (5). Fuel then goes through filter screen (4) and into passage (9) to the area below diameter (8) of valve (7). When the pres­ sure of the fuel that pushes against diameter (8) becomes greater than the force of spring (3), valve (7) lifts up. When valve (7) lifts, the tip of the valve comes off of the nozzle seat and the fuel will go through the nine 0.20 mm (.008 in.) orifices (6) into the combustion chamber. The injection of fuel continues until the pressure of fuel against diameter (8) becomes less than the force of spring (3). With less pressure against diameter (8), spring (3) pushes valve (7) against the nozzle seal and stops the flow of fuel to the combustion chamber.

FUEL SYSTEM

SYSTEMS OPERATION

The 8N7005 Fuel Injection N o:zzle ca n not be disassembled and no adjustments can be made.

FUEL TRANSFER PUMP (LATER) The fuel transfer pump is a piston pump that is moved by a cam (eccentric) on the camshaft for the fuel injection pump The transfer pump is located on the bottom side or the fuel injection pump housing. B50041X1

is pushed thru the outlet check valve (3) and out pump outlet port (8). Fuel also moves thru pump in let port (6) and in let check valve (7) to fill the area below piston (2). The pump is now ready to start a new cycle. B50042X 1

3

3

2

4

~>I t'r/~ ~

4

5

8 FUEL TRANSFER PUMP (START OF UP STROKE) (ARROWS INDICATE FUEL FLOW DIRECTION)

1. Push rod. 2. Piston. 3. OUllet check valve. 4. Pumping check valve. 5. Pumping spring. 6. Pump inlet port. 7. Inlet check valve. B. Pump out lei port.

5

6

7

B

FUEL TRANSFER PUMP (START OF DOWN STROKE) (ARROWS INDICATE FUEL FLOW DIRECTION)

1. Push rod. 2. Piston. 3. Outlet check valve. 4. Pumping check valve. 5. Pumping spring. 6. Pump inlet port. 7. Inlel check valve. B. Pump outlet port.

When the fuel injection pump camshaft turns. the cam moves push rod (1) and piston (2) down. As the piston moves down, in let check valve (7) and outlet check valve (3) close. Pumping check valve (4) opens and allows the fuel below the piston to move into the area above the piston. Pumping spring (5) is com­ pressed as the piston is pushed down by push rod (1 ). As the fuel injection pump camshaft continues to turn, the cam no longer puts force on push rod (1 ). Pumping spring (5) now moves piston (2) up. This causes pum ping check valve (4) to close. Inlet check val ve (7) and outlet check valve (3) will open. As the piston moves up, the fuel in the area above the piston

FUEL TRANSFER PUMP (EARLIER) The fuel transfer pump is a two-piston pump that is moved by a cam (eccentric) on the camshaft for the fuel injection pump. The transfer pump is located on the right side of the fuel injection pump housing. When the camshaft turns, the cam lifts push rod (10) up. The push rod lifts luge piston (9), push plate (6) and small piston (3). As the pistons move up, inlet check valve (5) and outlet check valve (8) close. Pumping check valve (7) in the large piston opens and fuel goes through the holes in the bottom of the large piston and fills the passages and chamber between the bottom of the farge piston and outlet check valve (8). As small piston (3) moves up, the pressure of the fuel above the piston increases and flows out of the pump through outlet (4). As the camshaft continues to turn, the cam lowers push rod (l0) down. Pumping spring (2) pushes small piston (3), push plate (6) and large piston (9) down. When the piston moves down, inlet check valve (5) and outlet check valve (8) open. Pumping check

7

SYSTEMS OPERATION

FUEL SYSTEM

valve (7) in the large piston closes and the pressure of the fuel below the check valve increases. Fuel now flows through the outlet check valve. A part of the fuel goes through outlet (4) and the remainder goes to the area above small piston (3). 2

3

5

As the large piston moves down, fuel from the fuel tank is pulled through inlet check valve (5) into the area between the large and small piston. The pump is now ready to start a new cycle.

4

Bypass valve (I) controls the outlet pressure of the fuel. If the fuel pressure goes beyond 170 to 280 kPa (25 to 40 psi), the bypass valve opens and fuel flows to the inlet of the pump.

6

OIL FLOW FOR FUEL PUMP AND GOVERNOR Oil from the side of the cylinder block goes to support (9) and into the bottom of front governor housing (4). The flow of oil now goes in three differ­ en t directions.

1

l5lINLET FUEL

§ PRESSURE FUEL

9

10

B9213Xl

FUEl TRANSFER PUMP SCHEMATIC (UP STROKE)

1. Bypass valve. 2. Pumping spring. 3. Small piston. 4. Outlet. 5. Inlet check valve. 6. Push plate. 7. Pumping check valve. 8. Outlet check valve. 9. Large piston. 10. Push rod.

2

3

4

6

5

1

A part of the oil goes to the rear camshaft bearing in fuel pump housing (5). The bearing has a groove around the inside diameter. Oil goes through the groove and into the oil passage in the bearing surface (journal) of camshaft (7). A drilled passage through the center of the camshaft gives oil to the frvnt camshaft bearing and to the thrust face of the cam­ shaft drive gear. Drain hole (6) in the front of fuel pump housing (5) keeps the level of the oil in the housing even with the center of the camshaft. The oil returns to the oil pan through the timing gear housing. Oi I also goes from the bottom of the front governor

housing through a passage to the fuel pump housing

and to governor servo (2). The governor servo gives

hydraulic assistance to move the fuel rack.

~-~--

The remainder of the oil goes through passages

to the rear of rear governor housing (3), through air

fuel ratio control (1) and back into another passage

in the rear governor housing. Engines that do not

have an air fuel ratio control have a cover with an

oil passage to complete the oil flow. Now the oil goes

into the compartment for the governor controls.

Drain hole (8) keeps the oil at the correct level. The

oil in this compartment is used for lubrication of

the governor control components and the oil is the

supply for the dashpot.

8

The internal parts of the governor are lubricated

by oil leakage from the servo and the oil is thrown by

parts in rotation. The flyweight carrier thrust bear­

ing gets oil from the passage at the rear of the

camshaft.

rn INLET FUEL Iii PRESSURE FUEL

9 B9214X1

FUEL TRANSFER PUMP SCHEMATIC (DOWN STROKE)

1. Bypass valve. 2. Pumping spring. 3. Small piston. 4. Outlet. 5. Inlet check valve. 6. Push plate. 7. Pumping check valve. 8. Outlet check valve. 9. Large piston. 10. Push rod.

8

10

Oil from the governor returns to the oil pan

through a hole in the bottom of the front governor

housing and through passages in the support and

cylinder block.

.;/

SYSTEMS OPERATION

FUEL SYSTEM

2

5

4

I

,I

~ PRESSURE OIL

9

OASHPOT OIL

\ 825650Xl

FUEL PUMP AND GOVERNOR 1. Air fuel ratio control. 2. Servo. 3. Rear governor housing. 4. Front governor housing. 5. Fuel pump housing. 6. Drain hole. 7. Camshaft. 8. Drain hole. 9. Support.

GOVERNOR The governor controls the amount of fuel needed by the engine to maintain a desired rpm. The governor flyweights (8) are driven directly by the fuel pump camshaft. Riser (l0) is moved by flyweights (8) and governor spring (l). Lever (7) connects the riser with sleeve (2) which is fastened to valve (3). Valve (3) is a part of governor servo (5) and moves piston (4) and fuel rack (6). The fuel rack moves toward the front of the fuel pump housing (to the right in the illustration) when moved in the FU EL OFF direction. The force of governor spring (I) always pushes to give more fuel to the engine. The centrifugal (rotating) force of flyweights (8) always push to get a reduction of fuel to the engine. When these two forces are in balance (equal), the engine runs at a constant rpm.

When the engine is started and the governor is at the low idle position, over fueling spring (9) moves the riser forward and gives an extra amount of fuel to the engine. When the engine has started and begins to run, the flyweight force becomes greater than the force of the over fueling spring. The riser moves to the rear and reduces the amoun~ of fuel to the low idle requirement of the engine. When the governor control lever is moved to the high idle position, governor spring (I) is put in compression and pushes riser (10) toward the flyweights. When the riser moves forward, lever (7) moves sleeve (2) and valve (3) toward the rear. Valve (3) stops oil flow through governor servo (5) and the oil pressure moves piston (4) and the fuel rack to the rear. This increases the amount of fuel to the engine. As engine speed increases, the flyweight force increases and moves the riser toward the governor spring. When the riser moves to the rear, lever (7) moves sleeve (2) and valve (3) 9

SYSTEMS OPERATION

FUEL SYSTEM

forward. Valve (3) now directs oil pressure to the rear of piston (4) and moves the piston and fuel rack for­ ward. This decreases the amount of fuel to the engine.

Governor Servo The governor servo gives hydraulic assistance to the mechanical governor force to move the fuel rack. The govemor servo has cylinder (3), cylinder sleeve (4), piston (2) and val ve (I).

~

}

11

GOVERNOR SERVO (Fuel on position)

89136-Jx3

GOVERNOR 1. Governor spring. 2. Sleeve. 3. Valve. 4. Piston. 5. Gov­

ernor servo. 6. Fuel rack. 7. Lever. 8. Flyweights. 9. Over

fueling spring. 10. Riser. 11. Spring seat. 12. Stop

bolt. 13. Torque spring. 14. Power setting screw. 15. Tor­

que rise selting screw. 16. Stop collar. 17. Stop bar. 18.

Load stop bar.

When the tlyweight force and the governor spring force become equal, the engine speed is constant and the engine runs 8t high idle rpm. High idle rpm is adjusted by the high idle adjustment screw. The adjustment screw 1imits the amount of compression of the governor spnng. With the engine at high idle, when the load is increased, engine speed will decrease. Flyweights (8) move in and governor spring (1) pushes riser (10) forward and increases the amount of fuel to the engine. As the load is increased more, governor spring (1) pushes riser (10) farther forward. Spring seat (11) pulls on stop bolt ( 12). Stop collar ( 16) on the opposite end has power setting screw (14) and (on engines so equipped) torque rise setting screw (15) that controls the maximum amount of fuel rack travel. The power setting screw moves forward and makes contact with load stop bar (18) or torque spring (13). This is the balance point. For engines with a torque spring, if more load is added to the engine, engine speed will decrease and push riser (10) forward more. This will cause power setting screw (14) to bend (deflect) torque spring (13) until torque rise screw (15) makes contact with stop bar (17). This is the point of maximum fuel to the engine.

10

B9220X1

D

B

1. Valve. 2. Piston. 3. Cylinder. 4. Cylinder sleeve. 5.

Fuel rack. A. Oil inlet. B. Oil outlet. C. Oil passage. D. Oil

passage.

When the governor moves in the FUEL ON direc­ tion, valve (1) moves to the left. The valve opens oil outlet (B) and closes oil passage (D). Pressure oil from from oil inlet (A) pushes piston (2) and fuel rack (5) to the left. Oil behind the piston goes through oil passage (C), along valve (l) and out oil outlet (B).

A

2

4

5

a LOW PRESSURE OIL B9222X1

GOVERNOR SERVO (Balanced position) 1. Valve. 2. Piston. 3. Cylinder. 4. Cylinder sleeve. 5. Fuel rack. A. Oil inlet. B. Oil outlet. C. Oil passage. D. Oil passage.

_lo'

SYSTEMS OPERATION

FUEL SYSTEM

4

When the governor spring and flyweight forces are balanced and the engine speed is constant, valve (1) stops moving. Pressure oil from oil inlet (A) pushes piston (2) until oil passages (C and D) are opened. Oil now flows through oil passage (D) along valve (1) and out through oil outlet (B). With no oil pressure on the piston, the piston and fuel rack (5) stop moving.

B92:24-1Xl

DASH POT

(Governor Moving to Fuel On)

1. Cylinder. 2. Piston. 3. Dashpot spring. 4. Spring seat. 5. Needle valve. 6. Check valve. 7. Oil reservoir.

GOVERNOR SERVO (Fuel Off Position) 1. Valve. 2. Piston. 3. Cylinder. 4. Cylinder sleeve. 5. Fuel rack. A. Oil inlet. B. Oil outlel. C. Oil passage. D. Oil oassaae.

When the governor moves in the FUEL OFF dir­ ection, valve (1) moves to the right. The valve closes oil outlet (B) and opens oil passage (D). Pressure oil from oil inlet (A) is now on both sides of piston (2). The area of the piston is greater on the left side than on the right side of the piston. The force of the oil is also greater on the left side of the piston and moves the piston and fuel rack (5) to the right. Dashpot

The dashpot helps give the governor better speed control when there are sudden speed and load changes. The dashpot has cylinder (1), piston (2), dashpot spring (3), needl~ valve (5) and check valve (6). Piston (2) and spring seat (4) are fastened to dashpot spring (3). When the governor moves toward FUEL ON, spring seat (4) and piston (2) move to the right. This movement pulls oil from oil reservoir (7) through check valve (6) and into cylinder (1).

1 DASHPOT

(Governor Moving to Fuel Off)

89224Xl

1. Cylinder. 2. Piston. 3. Dashpot spring. 4. Spring seat. 5. Needle valve. 6. Check valve. 7. Oil reservoir.

When the governor moves toward spring seat (4) and piston (2) move to movement pushes oil out of cylinder needle valve (5) and into oil reservoir

FUEL OFF, the left. This (1), through (7).

If the governor movement is slow, the oil gives no restriction to the movement of the piston and spring seat. If the governor movement is fast in the FUEL OFF direction, the needle valve gives a restriction to the oil and the piston and spring seat will move slowly.

11

SYSTEMS OPERATION

FUEL SYSTEM

AIR FUEL RATIO CONTROL 3 4

2

6

5

III

DRAIN OIL

1m FLOWING

11

10

9

8

1

B31943·2X1

OIL

AIR FUEL RATIO CONTROL (Engine Stopped) 1. Inlel air chamber. 2. Diaphragm assembly. 3. Internal valve. 4. Oil drain passage. 5. Oil inlet. 6. Stem. 7. Spring. Piston. 9. Oil passage. 10. Oil chamber. 11. lever.

a.

2

6

5

4

3

)

§INLET MAN. PRESSURE ODRAIN OIL ~FLOWING OIL

B3194J-1Xl

1

B

9

10

11

AIR FUEL RATIO CONTROL (Increase in Inlet Air Pressure) 1. Inlet air chamber. 2. Diaphragm assembly. 3_ Internal valve. Piston. 9. Oil passage. 10. Oil chamber. 11. lever.

4. Oil drain passage. 5. Oil inlet. 6. Stem. 7. Spring.

a.

'