Yanmar YM155d User manual

1 MAKING EFFECTIVE USE OF THIS SERVICE MANUAL
This manual discusses the maintenance standards and troubleshooting procedurestobeemploy-
ed from the standpoint of the repairman, inorder that the tractor can perform intop condition
through correct servicing procedures.
Repairs conducted by estimations or force of habit could lead to unexpectedaccidents and seri-
ous trouble. Always carry out repairs in
a scientific and accurate manner.
= SERIAL NUMBERS
Do not limit your work merely to the actual repair work alone but always strive to carry out
dependable servicing, including such efforts
as noting down the servicing history of your tractor
and keeping maintenance records.
In order to easily process any claims it is imperativethat the full details and serial numbers of
parts be clearly written on the prescribed form, and then sent to the dealer for forwarding to
the manufacturer.
/p,&s-
Drive

CONTENTS
I . Nomenclature ................ 1
.
I I Specifications ................. 5
1 . Specifications .................. 5
2 Power train ................... 10
Power train (1) ................. 10
Powertrain (2)
................. 11
Power train (3)
................. 12
Power train (4)
................. 13
3
. Transmission sectional view ........... 14
4
. Electricwiring diagram ............ 15
5
. Fuel system ................... 17
6
. Engine lubricatingsystem ............ 17
7
. Coolingsystem ................. 18
8
. Transmission lubelhydraulic system ..... 18
Ill . Tractor separation ............. 19
IV . .Disassemblysequence ............ 20
V . Enginedisassembly ............. 31
VI . Engineconstructionand maintenance . 35
................. 1 . Cylinder liners 35
2
. Pinons ..................... 36
3
. Pistonrings .................. 37
4
. Pistonpin .................... 38
5
. Connectingrods ................ 39
6
. Crankshaft ................... 40
.................... . 7 Camshaft 43
................. 8 . Cylinder head 45
9
. Combustionchambers ............. 46
10 . Rocker arm assembly ..............
48
.......
11 . Injectionpumpand injectionvalve 48
12 Governor .................... 53
13 . Lubricatingoil pump ..............
53
.
14 Cwlingsystem ................. 54
15 . Gears ..................... 54
.......
16. Oil seals. O-rings and ball bearings
54
VII . Engine assembly ............... 55
VI II . Engineadjustments ............ 61
1 . Governorlinkage ................ 61
2 Valve clearance ................. 61
3
. Fuel injectiontiming .............. 62
4
. Fan belttension ................ 63
5
. Air venting (bleeding) .............. 63
...... 6 . Other measurementsand inspections
64
IX . Electrical equipment ............ 65
1 . Battev ..................... 65
2
. Governor & current limiter ........... 67
3
. Inspectionand characteristics .......... 69
4 . Cautionsduringhandlingand assembly ..... 70
5 . Instructionsfor disassembly and assembly ... 71
6 . Maintenanceand inspection ........... a1
7 . Starter motor .................. 72
8
. Thermostart (optional) ............. 78
........... . 9 Turnsignal lights (optional) 77
10
. Water temperature indicator light ........ 77
11 . Engine lubeoil pressure ............. 77
12 . Horn ...................... 78
13
. Lights ..................... 78
74
. Safety startswitch ............... 78
X . Tractor constructionand maintenance . . 79
1 . Clutchand relevantitems ............ 79
.........
2 Transmissionand relateditems 83
3 . Brake ...................... 89
4
. Hydraulic liftdevice .............. 90
5 . Steering ..................... 93
6
. Frontaxle and rear axle ............. 95
XI . Tractorassembly .............. 103
1 . General assembly ............... 103-
2 Transmissionassembly ............ 105
2-1 P.T.O. drivingshaft assembly ...... 105
2-2 'P.T.o. fork shaft assembly ....... 106
2-3 Front P.T.O. shaft assembly
(YM135D . YM155D) .......... 107
2-4 Front P.T.O. shiftshaft assembly
(YM135D . YM155D) .......... 107
2-5 Drivenshaftassembly .......... 108
2-6 Counter shaft assembly ......... 109
2-7 Low-highshift shaft assembly ...... 110
2-8 Mainchange shaft assembly ....... 110
2-9 The fork of the 2ndl3rd speed shift
shaft assembly
............. Ill
2-10 Reversellstspeed shift shaft
assembly
................ 112
2-11 Mainshaft and transmissionfront
cover assembly
............. 113
2-12 Gear shaft lever assembly
........ 114
2-13 P.T.O. reductionshaft assembly
..... 115
2-14 Connectingshaft assembly
....... 115
2-15 P.T.O. shaftassembly
.......... 116
2-16 Differential lockshaft aisembly
..... 117
2-17 Finalreductionpinionand rear
...........
axle shaftassembly 118
...........
2-18 Differential device 120,
2-18 (a) Disassembly ............. 12
2-18 (b) Assembly
............... 122
2-19 Cam
. differential lock assembly ..... 122

3 . Frontaxle assembly
.............
3-1 Frontaxle assembly (YM155D .
YM135D) ................
3-2 Frontaxle assembly (YM155. YM135)
.
3-3 Frontaxle assembly (YM155D.
. YM135Dl ...............
3-4
Differential device assembly (YM155D .
YM135D. front axle) ..........
4 . Center pinassembly .............
4-1 For YM155D & YM135D .......
4-2 For YM155 & YM135 .........
5 . Brakedrum assembly .............
6 . Hydraulic system assembly ..........
6.1 Cylinderhead assembly .........
62 Lifting shaft. lift arms. liff crank.
hydraulic piston rod assembly
.....
6-3 Control valve assembly .........
6-4 Hydrauliccontrol fork. hydraulic
control lever assembly
.........
6-5 Auto-return rod. operator's seat
bracket assembly
............
6-6 Slow returnvalve assembly .......
n 6-7 Lift arm assembly ............
68 Operationalprecautionpolnts .....
...........
XI1. Tractor adjustments 141
XI II . Tractor trouble-shooting ........ 142
1 . Engineand related items ........... 143
2 Electricalsystem ............... 145
3
. Brakesystem ................. 745
4
. Clutch and relateditem ........... 746
5
. Transmission and relateditems ....... 147
6
. P.T.O. and relateditems ........... 147
7 . Hydraulicsystem ...............
148
8 . Steering andsuspensionsystem ....... 149
XIV. Regular inspections ........... 150
.......
XV. Tightening torque ratings 151
XVI . Maintenanceequipment and tools . . 153

I. NOMENCLATURE
Model
YM135
(1) Muffler
(2) Brakepedal
(31Step
(4) Differential lock pedal
(5) Instrumentpanel
(6) Drag rod
(7) Knucklearm
(8) Bumper
(9) Battery
(101 Radiator
(111 Hood
(12) Engine
(13)Air cleaner
(14) Fuel tank
(15)Throttle lever
(16) Steering wheel
(17)Gear shift lever
(18)
P.T.O. shift lever
(19) Hydrauliccontrol lever
(20) Assist bar
(21
) Operator'sseat
(22) Fender
(23) Lift link

Model
YM155
(24)Top link
(25)Top link hinge
(26) P.T.O. shaft
(27) Lower link
(28) Liftarm
(29) Rear tire
(30) Rear wheel
(31 ) Brake
(32) Transmission case
(33) Brake rod
(34) Pitmanarm
(35) Range
.. - shift . lever
(36) Steering gear box
(37) Clutch pedal
(38) Clutch housing
(39)Starter motor
(40) Kingpin
(41 Front wheel
(42) Front tire
(43) A.C. Generator
(44) Headlight
(45) Front axle center-pin

Model
YM135D
(1) Muffler
(2) Brakepedal
(3)Step
(4) Differential lock pedal
(5) Instrumentpanel
(6) Drag rod
(7) Nuklearm
(8) Bumper
(9) Battew
(10) Ragiator,
(11 ) Hood
(12) Engine
(13) Air cleaner
(14) Fueltank
(15)Throttle lever
(16) Steering wheel
(17) Gear shift lever
(18) P.T.O. shift lever
(19)Hydrauliccontrol lever
(20)Assist bar
(21
) Operator's seat
(22) Fender
(23) Lift link
A
(24)Top link

Model
YM155D
(25)Top link hinge
(26) P.T.O. shaft
(27) Lower link
(281Liftarm
(291Rear tire
(30) Rear wheel
(31
1 Brake
(32)Transmission case
(331Brake rod
(34) Frontwheel drive lever
(35) Pitmanarm
(36) Range shaft lever
(37)Steering gear box
(38) Clutchpedal
(39) Clutch housing
(401Starter motor
(41 I Frontwheel
(42) Fronttire
(43) A.C. Generator
(44) Headlight
(45) Frontaxle center pin
(461 Range shift lever
(47) Frontaxle
(48) Front differential
(49) Frontdrive propeller

II. SPECIFICATIONS
1. SPECIFICATIONS (1)
1 Item I Unit / YM735 I YM735D I YM155 I YM155D 1
I I
Cylinder liner type
I I I
Wet type
2T73AEngine model
EN-
Cylinder layout
i Bore stroke
I ~vcle 1 I 4-strokecvcle I
2TR13AEngine
Number of cylinders
Vertical inline
2.874 x 2.953 2.953
x 2.953
jn I 173mm x 75mml I
(75mmx 75mml
GlNE
I
2
block Typeof engine
Combustion chamber type
Valve system
Displacement
Comoression ratio
[ngineweight 1 lbs 1 242.3(llOkgI ! 253.3(115kg)
Diesel engine
( Maximumoutput
Maximum torque
/ Pistion I Compressionrings 1 I 3
1 Precombustionchamber
cu. in.
hplrpm
Overhead valves
38.3 (627cc)
I
40.4 (662cc)
23 : 1
L
25.312400 28.912200
"' FL 1 (3.5 krml2400) 1 14.0 k~-m/2200)
13/2700
Fuel
system
1512700
rings
/ Scraper rings
I
1 . <
Injection pump plunger diameter I In. I 0.2756 (7mml
1
Enginestarting 1 1 Electricstarting
Ignition
lnjection timing
Injection pump
type
0.2756 (7mml
Injectionplunger stroke .
Injectionvalve type 1
Injection valve diameter 1 ~n.
Valve
t~ming
I Compression ignition
Pi 24'f lo beforeT.D.C.
Yanmar Bosch PFR 2K
~n.
lnjectlon pressure
Injection order
I Fuel
Fuel tank capaciry
Speed control method
Semi throttletype
0.1958 (5mm)
2.276 (160kglcm2 1
1-2
Diesel oil
psi
U.S.ga1. 2.5 (9.5 1)
Intake
valves
4.0 (152)
Open I degree I 20' before T.D.C.
Closed
/ degree / 50' after B.D.C.
i
Exhaust
valves
All speed mechanical type
Open I degree / 50' before B.D.C.
Closed
/ degree 20° after T.D.C.
0.0078 (0.2mm)
0.0078 (0.2mm)
~n.
Valve Intakevalves
clearances Exhaust valves
1 in.

A SPECIFICATIONS (2)
1 Item 1 Unit IYM135 YM135D YM155 YM155D 1
EN-
!61NE
Lubri-
cating
I
Lubricatingpumptype
system
Trochoid
.
system
I I
CHAS-
SIS
Heatdissipation method
system
Generatorcapacity
Current limiter
Batteryvoltage, capaciw
Thermostart plugtype (optionall
Power
train
Lubricatinssystem
Lubricatingoil capacity
Radiator
Forcefeed lubrication
S114-219 (Hitachi), D.C. compound motor
Electrical
I A.C. generator type 1 (GP8108(KOKUSAN) magneto revolving
Starter motor capacity
V-W
V-AH
U.S.ga1
Water-cooled
Cooling
Starter motor type
12-8.5
RS2130 (KOKUSANI
12-35
SH100-02 (HITACHI)magneticvalve type
Thermostancapacity
1 V-A
Clutch
I
Travel [Forwardl
1 MPH (kmlhl MPH (kmlh)
speed* 1st 0.71 (1.14)
1 0.67 (1.071 I
0.44 (2.0 1)
Coolingsystem
V-KW
12-13
Trans-
mission
r'\
(*Difference in specificarion depending on serial number)
'12-1.2
Mechanicaldry single plate
7.09
x 4.92 x 0.33
(180mm x 125mm x 8.4mrn)
20.4 (132cm2 )
97.7 (13.5 kg-m)
Clutchtype
Fac~ng(outsidediam.
x insidediam. x
thickness
Facing area
Statictorsue capacitv
Transmission type
In.
sq. in.
ft. Ibs
Mechanical. constantselective mesh gears
combination
Transmission meeds
1
6-speedfor forward, 2-speedfor reverse

system
Item
I /
Unit
in.
degree
degree
in.
CHAS-
SIS
/ King-pininclination ( degree ( 7O 1 6" 1 7O 1 6O
Steer- 1 Steering svstem Ball - screw 1
lOGA 1 10GA
I
Option- Front Tiresize /20x8.00-10-4PR- 1 6-12-2PR-FD
Ing
system
Tires
/ al tires I wheels I
PD /
YM135
Running
gear
I I I
Tirepressure
/ lb/in2 124.2 11.7 kg/cm2) 1 17.1 11.20 kg/cm2)
1
Rims 5JA-12
YM135D
Rear axle type
Gear ratio
Steering wheel diam.
Gear box oil capacity
I I
wheels Tire pressure ( psi 125.6 (1.8 kg/cm2) 1 22.8 (1.6 kg/cm2)
Rims I 5Xk-16 1 5Zk-16
Front
wheel
align-
ment
Semi-floating
0.16-0.32 (4-8mm)
3O
in.
U.S.ga1.
psi
Front
wheels
I option-/Rear I Tiresize i 127~8.50-15-~PR- 1 8-16-4PR-FD I
YM155
Toe-in
Camber
Caster
Trail
0'
0
Tire size
Tire pressure
Rims
al tires
15.4
: 1
-
Brakes
YM755D
-
2.5O
0.43 (11
mm)
18.9 : 1
wheels PD
Tire pressure psi 11.4 (0.8 kg/cm2
1
22.8 (1.6 kg/cm2)
Rims 7001 x 15DT 5%K-16
Typeof main brakes Internalexpansionmechanical brakes
Parking braketype Lockingfoot brake
-
Liningsurface area
1
sq. in. 16.1 (104cm2)
.
I
Lining (width x thick- ~n. 0.98 x 0.16
x 4.09 (25 x 4 x 104mm)
ness x length)
o0
0
15.0 (380mm)
Brakedrum diameter in. 4.3 (IlOmm)
-
Methodof activation Main brakes by foot
Parkingbrake bv hand
I Type Hydraulic
2.5"
-
0.43 (11
mm)
15.8 (400mm)
Type of hydraulicpump Gear pump
Positionof pump
/ Infront of engine governor chamber
/ Purno drive
4
I 1 Claw couolino I
0.05 (0.2 1)
1 Pump discharge capacity. 1 ~.S.gal.j 3.76 (14.2 1) at 2700 rpm I
4.50-10-
2PR-FSR 5-12-
2PR-FSL
17.8 (1.25 kg/cm2 )
3.506 x / 4JA-12
17.8 (1.25 kg/cm2)
3.50 x 14JA-12
4.50-10-
ZPR-FSR 5-12-
2PR-FSL

/-. SPEC1FICATIONS (4)
With 3-point hitch 99.2" l2520rnml
,--
(*Difference in specification dependingonserial number)

SPECIFICATIONS (5)
.-
[DIFFERENCE INSPEClFlCATlONSj
ance
P.T.O. speed, r.p.m.
Maximumgrade
Braking distance
degree
ft.
6.2
(1.9m) 7.2
(2.2ml
35O
11.5 (3.5171)
7.2
(2.2m)
35O
11.5 (3.5m)
6.9
(2.lm)

,--.
2. POWER TRAIN (1)
NOTE: 'New'indicatesthoseafterNo. 51 001.
'Old'indicates those before No. 51 000.
No. of sear teeth 1

POWER TRAIN (2). , YM135(D)IYM155(D)POWER TRANSMISSIONSTRUCTURAL DRAWING
,--.
FRONTTIRE
Nore:
(I) 0 hold only ro YMISZDIYM135D
(2) * Shofi. nnd geor are combined
I
DIFFERENTIAL LOCK

POWER TRAIN (3)
YM135(D)/YM155(D) FRONTAXLE SECTIONAL VIEW
n
(BeforeSerial No. 51000)
FRONT DRIVINGSHAFT
-7
KNUCKLE ARM.(L)
FRONT AXLE CASE
BEVEL GEAR
DIFFERENTIAL PINION
DIFFERENTIAL
SIDE GEAR
LOWER FRONT GEAR CASE
DIFFERENTIAL
PINIONSHAFT
DIFFERENTIAL HOUSING BEVEL GEAR
FRONT AXLE SHAFT
FRONTGEAR CASE CAP
FRONTWHEELTIRE
2

POWER TRAIN (4)
Yhl135(D)/YrV:155(D)FRONT AXLE SECTIONAL VIEW
IAfter Serial No. 51001)
FRONT DRIVING SHAFT
7
r
FRONT AXLE (L)
FRONT AXLE CASE 7 \ i rKNUCKLE ARM (L)
FRONT WHEEL TIRE J'

3. Yh1135(D)/YM155(D) TRANSMISSION SECTIONAL VIEW
DIFFERENTIAL LOCK CLUTCH GEAR
DIFFERENTIAL, LOCK CAM COVER
FFERENTIAL LOCK CAM
#'
DIFFERENTIAL HOUSl
FINAL REDUCTION
GEAR HOUSING ASS
FINAL REDUCTI
PINION (Ll DIFFERENTIAL
INION SHAFT
BRAKE COVER
(
BRAKE COVER (Rl
FINAL REDUCTION
EAR AXLE SHAFT
FINAL REDUCTION GEAR REAR WHEEL HUB
REAR AXLE HOUSING IL) FINAL REDUCTION GEAR
REAR AXLE HOUSING IRI
FRONT P.T.O. SLIDING GEAR LOW-HI REDUCTION GEAR
LOW-HI SLIDING GEAR
FRONT DRIVING GEA
REVERSE GEAR NSMlSSlON HOUSING
REAR COVER
P.T.O. SHAFT
COUNTER SHAFT
1STlREVERSE
0. REDUCTION GEAR
MAIN CHANGE S .O. REDUCTION SHAFT
DRIVEN SHAFT
DRIVEN GEAR AL REDUCTION
GEAR HOUSING
DRIVEN GEAR E-WAY CLUTCH 10)
P.T.O. DRIVING SHAFT
TRANSMISSION HOUSING .O. REDUCTION GEAR

TURN TURN
SIGNAL SIGNAL
WORK LIGHT LEFT RIGHT
HEADLIGHT
LIGHT SWITCH
WATER TEMP
~NDICATORLIGHT (redl
WATER TEMP
OIL PRESSURE
Graan
BUTTON
SWITCH