5. Maintenance Specifications 1. Torque Values
5.1.3. Standard Torque Value Table
Refer to the following table for bolts other than described above.
Degree of Strength
3.6 4.6 4.8 5.6 5.8 6.6 6.8 6.9 8.8 10.9 12.9
(4A) (4D) (4S) (5D) (5S) (6D) (6S) (6G) (8G) (10K) (12K) Limit Value for Elasticity (kg/mm2)
20 24 32 30 40 36 48 54 64 90 108
M10 1.35 1.40 2.20 1.90 2.70 2.35 3.70 4.20 4.40 6.20 7.40
M10B1 1.50 1.60 2.50 2.10 3.10 2.80 4.30 4.90 5.00 7.00 8.40
M12 2.40 2.50 3.70 3.30 4.70 4.20 6.30 7.20 7.50 10.50 12.50
M12B1.5 2.55 2.70 4.00 3.50 5.00 4.60 6.80 7.70 8.00 11.20 13.40 M14 3.70 3.90 6.00 5.20 7.50 7.00 10.00 11.50 12.00 17.00 20.00 M14B1.5 4.10 4.30 6.60 5.70 8.30 7.50 11.10 12.50 13.00 18.50 22.00 M16 5.60 6.00 9.00 8.00 11.50 10.50 15.50 17.90 18.50 26.00 31.00 M6B1.5 6.20 6.50 9.70 8.60 12.50 11.30 17.00 19.50 20.00 28.00 33.50 M18 7.80 8.30 12.50 11.00 16.00 14.50 21.00 24.20 25.00 36.00 43.00 M18B1.5 9.10 9.50 14.50 12.50 18.50 16.70 24.50 27.50 28.50 41.00 49.00 M20 11.50 12.00 18.00 16.00 22.00 19.00 31.50 35.00 36.00 51.00 60.00 M20B1.5 12.80 13.50 20.50 18.00 25.00 22.50 35.00 39.50 41.00 58.00 68.00 M22 15.50 16.00 24.50 21.00 30.00 26.00 42.00 46.00 49.00 67.00 75.00 M22B1.5 17.00 18.50 28.00 24.00 34.00 29.00 47.00 52.00 56.00 75.00 85.00 M24 20.50 21.50 33.00 27.00 40.00 34.00 55.00 58.00 63.00 82.00 92.00 M24B1.5 23.00 25.00 37.00 31.00 45.00 38.00 61.00 67.00 74.00 93.00 103.00
Others:
1. The above torque ratings have been determined to 70% or so of the limit value for bolt elasticity.
2. Tension is calculated by multiplying tensile strength by cross section of thread.
3. Special screws should be tightened to 85% or so of the standard value.
For example, a screw coated with MOS2 should be tightened to 60% or so of the standard value.
Diameter B pitch (mm)
DivisionPart Inspected ItemNominalStandard ValueLimit for Repairing PointerRemarksNameValuefor AssemblyUse Inner dia. of liner for wearl111l111 ~ 111.022l111.122Replace liner CylinderAmount of liner projection0.03~0.08Must exist BlockThe flatness of upper surface of cyl. block0.050.05Correct with a surface grinderReferenced length : 200mm EngineHydraulic test for 1 minute (kg/cm2)4Replace if leaky Body Thickness of cyl.Before install1.4 Check torque value Cylinder head gasketAfter install1.2or replace gasket Head Cam height110109.9 ~ 110.1108.4Replace cyl. head Hydraulic test for 1 minute (kg/cm2)4Replace if leaky Outer dia. of pistonl110.801 ~ 110.959Replace liner Clearance between piston and liner0.041~0.2210.3Replace one worn more Piston1st ring3.50 Width of piston ring 2nd ring3.06~3.08Replace piston if groove width grooves Oil ring4.04~4.06is beyond specified value MajorPiston projection from cylinder block upper surface0~0.12Must exist Moving1st ring0.40~0.651.5 PartsPiston ring gap2nd ring0.40~0.651.5Replace ringStandard gauge inside Oil ring0.30~0.601.5diameter : N108 PistonWeight difference of pistons96g Replace piston Ring1st ring-- Piston ring 2nd ring0.07~0.1020.15Replace ring or pistonLimit for use is for side clearance Oil ring0.05~0.0850.15standard clearance Direction of ring gapCross install by 120° PistonOuter diameter of piston pinl42l41.994~42Replace piston pin PinClearence between piston pin and its bush0.009~0.015Replace one worn more
5.2. Maintenance Specification Table
Measure unworn portion beneath the rim of the upper side Measure at 13mm away from lower surface of pistonProjection difference between adjacent liners : 0.15 Torque value for cyl. head bolt : 24.5 kg . mMeasure unworn portion beneath the rim of the upper side
DivisionPart Check ItemsNominalStandard ValueLimit for CorrectionRemarksNameValuefor AssemblyUse Radial run-out of journal & pin0.01Correct with a grinder Diameter of journalN84N83.966~83.988N83 Diameter of pinN71N70.971~70.990N70 Ellipticity of journal & pin0.008 Concentricity of journal & pin0.010 Taper of journal & pin0.010 Crank Clearance between crank shaft & bearing0.052~0.1220.25Replace bearingShaft End play of crank shaft0.15~0.3250.5Replace thrust bearing Run-out of crank shaft0.1Adjust by a press if bended Balance of crank shaft (g . cm)
60Check dynamic balanceMeasure at 400 rpm MajorTorque value journal bearing cap bolt(kg
. m)
30Coat the bolt with engine oil Moving Crush of journal bearing0.19~0.22 Parts Oil seal for wear(crank shaft rear)Replace oil seal if oil leaking End play of con-rod0.170~0.2480.50Replace con-rod Clearance between con-rod bearing & crank pin0.034~0.0980.25Replace bearing Con-Clearance between small end bush & piston pin0.050~0.081 RodCrush of con-rod0.30~0.50 Side clearance of big-end & small-end0.50Replace con-rod Allowable weight difference per con-rods56g Torque value of con-rod bearing cap bolt (kg
. m)
18Coat the bolt with engine oil Diameter of cam shaft journalN57.86~57.88 Cam Clearance between cam shaft & cam bush0.12~0.170.24Replace cam bush Shaft End play of cam shaft0.28~0.430.6Replace thrust washer Run out of cam shaft 0.1Correct or replace the cam shaft TimingClearance between idle shaft bush & idle shaft0.025~0.0910.15 GearEnd play of idle gear shaft0.043~0.1670.30Replace thrust collar Back-lash between gears 0.16~0.280.35Correct or replace gear (cam, idle, crank and injection) Clean out foreign objects on joining surface
Measure in horizontal and vertical direction (against axial direciton) Measure at crown part not parting line Measure at No. 4 bearing (No. 1&7 bearing supported) Measure after tightening metal cap and releasing one stud Measure after installing the bearing and releasing one bolt Clean out foreign objects on joining surface
Use under-sized bearings respectively (0.25, 0.5, 0.75, 1.0)
DiviionPartInspected ItemNominalStandard ValueLimit for Repairing PointerRemarks NameValuefor AssemblyUse Diameter of intake valve stemN9N8.950~8.970N8.93 Replace valve & valve guide Diameter of exhaust valve stemN9N8.935~8.955N8.91 Clearance between valveIntake0.030~0.0650.15 Replace valve or valve guide stem and valve guideExhaust0.045~0.0800.15 Thickness of valve headIntake2.21 or more Exhaust2.21 or moreReplace valve Valve seat depressionIntake-0~0.3 Replace valve seatExhaust-0~0.3 Clearance between valve guide & cyl. head installing hole0.03 Concentricity between valve stem & valve head0.01~0.39 Clearance between valve guide &Intake26 valve spring seatExhaust26 Free length Approx. 64 Tension force kg 7066.5~73.566.5 Replace valve spring(when pressed to 41 mm) Straightness 1.0 Valve(along free length direction) Free lengthApprox. 60 Tension force kg 28.627.2~30.026.2 Replace valve springInner(when pressed to 38 mm) Straightness 1.0 Exhaust(along free length direction) valveFree lengthApprox. 71 springTension force kg 6662.7~69.367.7 Replace valve springOuter(when pressed to 41 mm) Straightness 1.0 (along free length direction) Valve clearance (at cold)Intake0.30 Adjust Exhaust0.30 Joining surfaces of valve stem & rocker arm Clearance between rocker arm shaft & rocker arm bush0.020~0.093 Diameter of rocker arm shaft for wearN24N23.75 Run out of push rod0.3
When replacing valve, replace valve guide alike Spread oil over valve guide and press it into the hole
Grind or replace if severely pitted on tip of rocker arm and stem
Replace one worn more. Without spring seat Replcae bush or shaft Replace Replace
Valve System
Intake valve spring
DivisionPartInspected ItemNominalStandard ValueLimit for Repairing PointerRemarks NameValuefor AssemblyUse Clearance between tappet & tappet hole of cyl. block0.035~0.0770.1Replace tappet TappetDiameter of tappetN20N19.944~19.965Replace tappet Tappet face in contact with cam---ReplaceReplace if severely worn or deformed OilOil pressure(at nominal speed) (kg/cm2)- 4.8Check oil leakage and Pressureclearance between each part Oil pressure(at idling speed) (kg/cm2)0.8~1.40.6Use recommended oil Oil Max. oil temp (c)---90 Must not exceed this valueTemp Short term peak oil temp (c)---100 Axial play of oil pump gear0.055~0.105-Replace gear or cover Lubricating Clearance between gear shaft & oil pump cover hole0.032~0.077Replace gear shaft or cover System OilClearance between driving gear bush & cover hole-0.040~0.094-Replace bush or cover PumpDiameter of gear shaftN17e7N16.950~16.968N16.950Replace gear shaft Diameter of driving gear bushN28e8N27.939~27.960N27.939Replace bush Backbetween crank gear & idle gear-0.15~0.250.8 Adjust back-lash lashbetween oil pump driving gear & indle gear-0.15~0.250.8 Oil pressure control valve kg/cm2-4.0~4.8-Replace valve ValveBy-pass valve for filter element kg/cm21.8~2.3-Replace valve OpeningBy-pass valve for full oil filter kg/cm2-4.0~4.8-Replace valve Pressure Relief valve for oil pump kg/cm2-8.5~11.5-Replace valve Spray nozzle control valve kg/cm2-1.5~1.3-Replace valve Oil FilterDamage of oil filter elementClean or replace
DivisionPartInspected ItemNominalStandard ValueLimit for Repairing PointerRemarks NameValuefor AssemblyUse pump speed 2000rpm Dilivery(M/min) water temp. 80Approx. 190Check the water passage Water
negative pressure 0.5 barFor any restrictions PumpClearance between impeller & housing0.35Replace if impeller & housing are intact CoolingPerpendicularity of pulley0.3Adjust by a bench press SystemFan belt depression (with thumb) Approx. 15Adjust CoolingOperating temp c80~8595 must not exceed this value WaterTemp.short term peak temp c105 ThermostatInitiating temp. (1 atm) c71-Replace Full opening temp c 86 or less-Replace if defective stroke : mimimum 8 mm Compression PressureCylinder compression pressure kg/cm22824Overhaul the engineAt normal operating temp, over 200 rpm Fuel pipe, injection pipe & nozzle holderRepair or replace Piping & for damage, crack, improper packing, etc. Others Fuel filter element for damage or dimpleReplace fuel filter Opening pressure of overflow valve kg/cm21~1.5Replace valve Projection height of nozzle from the head surface3.6~4.1Replace cyl.head & nozzle Shaft run-out0.1Replace rotor Rotor Bearing noiseReplace bearing Slip ring face for foulingCorrect by sand paper AC BrushBrush & itsBrush length147 Correct or replace if ElectricalAlternator springTension force g300255~345defective Devices PerformanceUnload speed rpm28V950 Output speed rpm28V, 40A5000 VoltagePerformanceRegulated voltage V27.5~29.5 Correct if terminal point RegulatorField relay cut-in voltate V8~12is defective
Fuel System
DivisionPart Inspected ItemNominalStandard ValueLimit for Repairing PointerRemarks NameValueforAssemblyUse Bolt tightening for looseCorrect Shaft run-outN140.1 ArmatureFront bearingN140.1 Gap between Center bearingN20.40.1 shaft & brush Pinion bearingN140.1 Diameter of commutatorN48N45Replace Out of round of commutator0.050.4Correct CommutatorDepth from undercut insulator to 0.5~0.80.2Correct surface of commutator Surface of commutatorCorrect by sand paper if fouled or damaged Electrical StarterLength 19.512.5 Devices Brush and
of brush Brush spring Spring forceg 130013001100 of brush Operating voltage V-16- Holding voltage V-8- Pinion stroke2222~23+1Correct or replace if severely worn or damaged Gap between pinion and ring gear3~5 Unload speed rpm4000105when 24V, 79A PerformanceLoad torque g. m 1.5-Replacewhen 390A Constrained torque kg
. m
3.3-when 750A
Correct or replace if •Surface of commutator is defective •Spring force or strength is improper •Brush is severely damaged or worn •Contact between brush & brush holder is improper
DivisionPart Inspected ItemNominalStandard ValueLimit for Repairing PointerRemarks NameValuefor AssemblyUse Battery terminalReplace if affected by rust or corrosion Pole plate, separator, cell, etc.Correct if foung to be defective Electrolyte for muddiness Temp convesion coeffiient (based on 20C) ElectricalBatterySpecific gravity of electrolyte1.12~1.281,200Adjust specific gravity Every extra +1C: -0.007 DevicesEveru extia -C: +0.003 Capacity (20 hrs rate) V-AH24-65B2 Terminal voltage12.610.8Recharging Height of electrolyte levelSpecified levelReplenish distilled water if low level Charging Warning lampCorrect electrical devices Indicationif abnormal noise The terminal of electrical wireCorrect Wiring for loosening or short Running-in engineAuthorized agencyRetighten head bolt (KR, KF...)after running in Compression pressure of cylinder kg/cm224~2824Correctat 200 rpm Compression pressure difference of each10%Correctat 200 rpm, 20c Inspection atcylinderagainst average Completion Oil pressure kg/cm23~4.8Adjust Test of outputContinuous max. outputValues for brand-new Fuel consumption105%engine are referred Idling speed rpm650~750Adjustto as 100%