Content .. 61 62 63 64 ..

Takeuchi compact excavator TB125, TB135, TB145 / diesel TNE / diesel Yanmar. Service Manual - page 63

iii

3.3.2.

Re-assembling Cam Shaft

･････････････････････････････････････････････････････････

3.3.3.

Install the hydraulic head CMP.

･･････････････････････････････････････････････････

3.3.4.

Assembling the Hydraulic Head

･･･････････････････････････････････････････････････

3.4.

Re-assembling the Governor

･････････････････････････････････････････････････････････････

3.5.

Combining Governor and Pump Bodies

････････････････････････････････････････････････････

ADJUSTMENT OF FUEL INJECTION PUMP AND GOVERNOR

･･････････････････････････････

4.1. Preparations

････････････････････････････････････････････････････････････････････････

4.2. Bottom clearance adjustment(Fuel Injection Timing)

････････････････････････････････････

4.2.1.

The bottom clearance adjusting value and the Cam classification

･････････････････････

4.3. Adjustment of Governor

･･････････････････････････････････････････････････････････････

4.3.1.

Adjustment of No Load Max. Engine Speed

･････････････････････････････････････････

4.3.2.

Adjustment of Fuel Limit Bolt

･････････････････････････････････････････････････････

4.3.3.

Adjustment of Torque-Rise Point

･･･････････････････････････････････････････････････

4.3.4.

Adjustment of Reverse Angleich

･････････････････････････････････････････････････････

4.3.5.

Adjustment of Staring Injection Amount

････････････････････････････････････････････

4.3.6.

Checking the Injection Stop

･･･････････････････････････････････････････････････････

FUEL INJECTION NOZZLE

･････････････････････････････････････････････････････････････

5.1. Functioning of fuel injection nozzle

････････････････････････････････････････････････････

5.2. Type/construction of fuel injection nozzle

･･･････････････････････････････････････････････

5.3. Fuel injection nozzle disassembly

･･････････････････････････････････････････････････････

5.4. Fuel injection nozzle inspection

･･･････････････････････････････････････････････････････

5.4.1. Washing

･････････････････････････････････････････････････････････････････････････

5.4.2. Nozzle

inspection

･････････････････････････････････････････････････････････････････

5.5. Fuel injection nozzle reassembly

･･････････････････････････････････････････････････････

5.6. Adjusting fuel injection nozzle

････････････････････････････････････････････････････････

5.6.1.

Adjusting opening pressure

････････････････････････････････････････････････････････

5.6.2. Injection test

･････････････････････････････････････････････････････････････････････

TROUBLESHOOTING

･･････････････････････････････････････････････････････････････････

6.1. Troubleshooting of fuel injection pump

･････････････････････････････････････････････････

6.2. Major faults and troubleshooting

･･････････････････････････････････････････････････････

TIGHTENING TORQUES FOR MAIN BOLTS AND NUTS

････････････････････････････････････

7.1. Pump part

･･････････････････････････････････････････････････････････････････････････

7.2. Mechanical governor part

･････････････････････････････････････････････････････････････

TOOLS

･･･････････････････････････････････････････････････････････････････････････････

1. For Safe Servicing

Most accidents are caused by negligence of basic safety rules and precautions. For accident prevention,

it is important to avoid such causes before development to accidents.

Please read this manual carefully before starting repair or maintenance to fully understand safety

precautions and appropriate inspection and maintenance procedures.

Attempting at a repair or maintenance job without sufficient knowledge may cause an unexpected

accident.

It is impossible to cover every possible danger in repair or maintenance in the manual. Sufficient

consideration for safety is required in addition to the matters marked CAUTION. Especially for safety

precautions in a repair or maintenance job not described in this manual, receive instructions from a

knowledgeable leader.

1.1. Warning Symbols

Safety marks used in this manual and their meanings are as follows:

Any matter marked

[NOTICE]

in this manual is especially important in servicing.

If not observed, the product performance and quality may not be guaranteed.

DANGER

indicates an imminently hazardous situation,

which if not avoided, WILL result in death or serious injury.

WARNING

indicates a potentially hazardous situation,

which if not avoided, COULD result in death or serious

injury.

CAUTION

indicates a potentially hazardous situation,

which if not avoided, may result in minor or moderate

injury.

1.2. Safety Precautions

Place allowing sufficient ventilation

Jobs such as engine running part welding and polishing the paint with

sandpaper should be done in a well-ventilated place

．

Failure to Observe
Very dangerous for human body due to the possibility of inhaling

poisonous

gas or dust

．

Sufficient wide and flat place

The floor space of the service shop for inspection and maintenance should
be sufficiently wide and flat without any holes.

Failure to observe
An accident such as a violent fall may be caused.

Clean

，

orderly arranged place

No dust

，

mud

，

0il or parts should be left on the floor surface.

Failure to Observe
An unexpected accident may be caused

．

Bright

，

safety illuminated place

The working place should be illuminated sufficiently and safety

．

For a job in

dark place where it is difficult to see

，

use a portable safety lamp. The

bulb

should be covered with a wire cage for protection.

Failure to observe
The bulb may be broken accidentally causing ignition of leaking oil.

Place equipped with a fire extinguisher

Keep a first aid kit and fire extinguisher c1ose at hand in preparation for fire
emergencies

Wears for safe operation

Wear a helmet

，

working clothes

，

safety shoes and other safety protectors

suited to the job. It is especially important to wear well-fiting work clothes.

Failure to observe
A serious accident such as trapping by a machine may occur.

Always use genuine parts

Jobs such as engine running part welding and polishing the paint with

sandpaper should be done in a well-ventilated place

．

Failure to Observe
Shortening of MP pump unit life or an unexpected accident may arise.

Always tighten to the specified torque if designated in the manual.

Failure to Observe
Loosening or falling may cause parts damage or injury.

Observe the following instructions with regard to waste disposal.

Negligence of each instruction will cause environmental pollution

Waste fluids such as engine oil and cooling water shall be

discharged into a

container without spillage onto the ground

Do not let waste fluids be discharged into the sewerage

，

a river

or the sea.

Harmful wastes such as oil, fuel, solvents, filter elements and

battery shall be

treated according to the respective laws and

regulations. Ask a qualified collecting company for example.

Use of appropriate tools

Use tools appropriate for the jobs to be done. Use a correctly sized tool for
loosening or tightening a machine part.

Failure to observe
A serious injury or engine damage may occur.

2. General information

2.1. Outline of MP pump

MP pump is a fuel injection pump that has been newly developed to be installed on Yanmar direct injection system diesel

engines for the purpose of complying with the regulation for the exhaust gas emission that are becoming tighter in the

future.

The fuel injection pump is a fuel distribution type pump that supplies fuel to each cylinder of the engine through a

distribution shaft by using a single plunger unlike conventional rail system or distribution system pumps.

Pump name plate

ID code for Exh.gas regulation

FIE ASY code

ID code for production

Serial numbers

Injection Pump No.

Fuel Injection Pump Asy. code

2.2. Specifications

Model

YPD-3MP2 YPD-4MP2 YPD-4MP4

Applicable Engine

3TNV82A /84(T)/88

4TNV84(T) /88

4TNV94

/98(T)/106(T)

Plunger Diameter (mm)

9mm

10mm

Max. Cam Lift (mm)

8.1mm

10mm

Governor-System Mechanical

All

Speed

Governor

Fuel Injection Timing Control

System

Built-in Hydraulic Control Timer

Fuel feed pump

Forced Lubrication System With Trochoid Pump

Lubrication system

Engine System Oil

Dry Weight (kg)

8.4

8.6

11.5

2.3. Outline of fuel injection pump

Yanmar distribution type fuel injection pump YPD-MP consists of a hydraulic head that is equipped with a single plunger, a

single distribution shaft, and delivery valves for each individual cylinders, a pump housing that includes camshafts, and a

governor, all of which are integrated into the main unit of the pump.

For the feed of the fuel, the plunger moves up / down and the distribution shaft rotates with the revolution of the camshaft

to distribute the fuel among the cylinders individually.

Specifically, one revolution of camshaft completes three cycles (for three cylinder engine) of a process, including switching

over to the high pressure flow path to each cylinder with the distribution shaft, opening delivery valve, high pressure pipe,

fuel injection valve, and engine cylinders in this order. This process is repeated by the revolution of the camshaft.

The Flow of the Fuel

Fuel filter

Electric fuel
feed pump

Fuel tank

Engine crankcase

Accumulator

Overflow
orifice

Timer piston

Plunger

Distributor
shaft

Torochoid pump

Fuel return

Pressure control valve

Fuel injection pipe

Nozzle

Injection pump

tappet

Oil seal

joint

Engine

oil

Cam

High pressure gallery

Low pressure gallery

orifice

Water separator

12/48

Engine coolant

Thermo-element

2.4. Construction of MP-Pump

2.4.1. Fuel Injection Part

Holder (delivery)

Plug (distribution shaft)

Plug (C.W.)

Joint (C.W.)

Thermo element.

Holder (timer)

Piston (timer)

Delivery valve CMP.

Sleeve (distribution shaft)

Removal stop
(Transmission shaft)

Hydrauric head

Packing (timer)

Barrel (plunger)

Sleeve (control)

Retainer (spring)

Spring (plunger)

Tappet (roller)

Roller

Camshaft

Flange

Plunger

Plug (barrel)

Joint (distribution shaft)

Distribution shaft

Transmission shaft

Strainer (A)

F. O. feed pump CMP

Control rack

Whirl-stop (tappet)

Accumulator

Spring (accumulator)

Plug(accumurator)

Joint (FO inlet)

Joint (overflow)

Strainer (B)

Drive gear A

Drive gear B

2.4.2. Governor Part

2.4.2.1. Construction of Governor

Usage condition of diesel engines are extremely varied

，

with a wide range of loads and speeds

．

The governor plays an

important role in the operation of the engine by quickly adjusting the position of the control rack to control the amount of

fuel injected, according to changes of engine speed.

It also automatically controls the engine to prevent engine speed from

exceeding the maximum ,and

keeps the engine

from stopping.

Mechanical governor

The governor weight mounted on the end of the fuel injection pump cam shaft rotates around the governor support pin,

driven by the cam shaft, and is forced outwards by the centrifugal force acting on the weight

．

The thrust force acting on the cam shaft due to this centrifugal force acts on the lower part of the tension lever through the

sleeve A starting excess fuel spring is mounted on the bottom of the tension lever

．

0ne end of the governor spring is hooked to the right upper end of the tension lever, and the other end to the spring lever

of the control lever shaft.

Angleich spring assembly

Stop solenoid

Governor case cover

Governor lever CMP

Sleeve (governor)

Link

Spring (governor)

Control lever

Governor weight

Shaft (Control lever)

Regulator lever

Shaft (Governor lever)

Fuel limiter CMP.

Torque spring

Camshaft

As the spring lever and control lever are mounted on the same shaft, when the control lever is turned towards full, the

governor spring is pulled and the load gradually increases.

Since the tension lever can move freely around the governor shaft on the player bearing, as speed increases and the

shifter is pushed to the left

，

the tension lever rotates clockwise, and when speed decreases

，

the tension lever rotates

counterclockwise.

The governor lever rotates smoothly on the second shaft installed on the tension leveb. The bottom part of this lever is in

contact with the sleeve through the shifter, which is in contact with the bottom of the tension lever through the excess fuel

spring. It therefore moves with the tension lever according to increases

／

decreases in engine speed.

The top of the governor lever is connected to the fuel pump control rack through the governor link. The movement of the

lever controls the volume of fuel injected by the pump. When speed increases the lever rotates clockwise to cause the

control rack to reduce fuel and when speed decreases the lever rotates counterclockwise to cause the control rack to

increase fuel, thus engine speed is controlled.

The top of the tension lever comes in contact with the stopper built into the top of the governor case to limit the maximum

fuel injection volume.

(1) Shape of control and stop levers

The control and stop levers that operate the governor

have different shapes depending on engine design and

method of attachment, as seen in the pictures below.

The motion of the control lever is regulated by the maximum speed adjustment bolt and the idling adjustment bolt. This

maintains the necessary engine speed.

(2) Engine stop device

The magnetic solenoid is equipped to stop the engine.

(3)Torque rise equipment

As mentioned before

，

this governor has a structure that allows you to equip it with an anglich and/or torque spring as

torque rise equipment. In this way the requirements for different engines can full filled.

Stop solenoid

Angleich spring CMP

Torque spring CMP

Link

Decrease

Injection volume

2.4.2.2. Function of Governor

(1) Function of governor

Following is a representation of the movement characteristics of the control rack at respective speeds

，

when the speed

rise from 0,with the governor control lever at the maximum speed position:

A-B : Fuel volume condition during starting. Volume is controlled by excess fuel spring.

B-C : The rack moves towards decrease after engine starts and speed increase as the load of the excess fuel spring is

overcome by the centrifugal force of the governor weight.

C-D : High torque at low speed is developed by increasing fuel injection volume equivalent to the angleich stroke.

D-E : Condition when the thrust force exceeds that of the angleich spring force on the bottom of the tension lever and it

gradually pushes the rack to decrease fuel when engine speed increases.

E-F : Condition when both right and left ends of the

shifter come in contact with the sleeve and the bottom of the tension

lever, and the control rack is kept at the normal position by the stopper.

（

max

．

injection volume position on models not

equipped with an angleich spring)

F :

Point when governor starts to take effect.

This is the rated output of the engine

．

F’ : Point when governor start to take effect on models with torque spring

．

G : Continuous rating point

（

usually 85

－

％

injection volume of F point).

H : No load max

．

speed

L :

Low-idle position

(2) Starting control

Moving the control lever to the max

．

speed position pulls the governor spring, and moves the tension lever until it comes in

contact with the control stopper.

When this is done

，

the excess fuel spring provided in between the tension lever and governor lever holds the control rack

at the maximum starting injection volume position R

A-B

After the engine is started, the excess fuel spring is compressed when the centrifugal force of the governor weight

overcomes the set of the excess fuel spring as speed exceeds N

, speed goes from B to C' (on models with angleich

spring ) or B to C(on models without angleich spring ). The rack reaches the position of R

where the governor lever and

tension lever are interlocked.

（

）

Idling

When the control lever is returned to the idling position after the engine is started. the governor spring tension decreases

and the tension lever descends clockwise, and the governor weight load keeps the governor spring and the excess fuel

spring load in equilibrium to maintain idling speed at (R

(4) Max speed

The angle of the control lever is set at determined

engine speed. The governor keeps engine speed

constant by adjusting sped when load changes.

For example, if the operator moves the control lever

with the link from the idling position to max. Output,

governor spring tension increases, the tension lever is

pulled until it comes in contact with the full load stopper,

the movement of the governor lever is transmitted

to the control rack via the link, maintaining the full load

rack position, and engine sped increase until the

governor weight thrust load and governor spring

tension come into equilibrium at full load max. Speed.

(5) Necessity and function of angleich

The governor must satisfy the required injection curves

represented in the diagram below in order to obtain

sufficient output at low speed, and not emit black

smoke at high speed. the angleich spring was devised

to provide for maximum torque at low sped by setting

injection volume at point A, and shifting injection

volume to point B' at high engine speed.

The angleich spring is mounted to the part of the

tension lever (however some engine are not equipped

with an angleich spring depending on usage and speed

range utilized).

When engine speed is low, the governor weight cannot

compress the angleich spring as the angleich spring

load is lager than the governor weight, thrust load, and

the control rack is held at a position (R

) to increase

injection volume.

Furthermore, as engine speed rise, the angleich spring

is gradually compressed as governor weight thrust load

increases and exceeds angleich load, before high

speed control is effected. When the governor lever and

the bottom of the tension lever come into contact (end

of angleich stroke), injection volume is reduced by that

amount, and the rack reaches the rated position (R

Content .. 61 62 63 64 ..