Mitsubishi 4DQ50 Service Manual Download

Page: 1 / 116

SERVICE MANUAL

三菱ディーゼルエンジン

MITSUBISHI
DIESEL ENGINE

4DQ50

MITSUBISHI HEAVY INDUSTRIES, LTD.
No. 5-1, Marunouchi, 2-chome Chiyoda-ku, Tokyo Japan
Phone: Tokyo (03) 212-3111 Telex: J22282, J22443 HISHIJU

SERVICE MANUAL

99609-50000
DEC 1985

Summary of Contents for 4DQ50

Page 1: ...ィーゼルエンジン三菱ディーゼルエンジン MITSUBISHI DIESEL ENGINE 4DQ50 MITSUBISHI HEAVY INDUSTRIES LTD No 5 1 Marunouchi 2 chome Chiyoda ku Tokyo Japan Phone Tokyo 03 212 3111 Telex J22282 J22443 HISHIJU SERVICE MANUAL 99609 50000 DEC 1985 ...

Page 2: ......

Page 3: ...MITSUBISHI DIESEL ENGINE MODEL 4DQ5OW ...

Page 4: ...MITSUBISHI DIESEL ENGINE MODEL 4DQSOC ...

Page 5: ...d weather 7 8 1 Starting in cold weather 7 8 2 General instructions 7 9 Handling in the hot season 8 CHAPTER 2 FUEL OIL AND COOLING WATER 9 1 Fuel 9 2 Engine oil 9 2 1 Quality required of engine oil 9 2 2 Recommendable classes of engine oil 9 2 3 Time to change engine oil 10 3 Diaphragm oil 10 4 Cooling water 10 4 1 Required quality 10 4 2 Handling of cooling system 10 CHAPTER 3 REGULAR SERVICING ...

Page 6: ...ing 24 4 3 Checkup of nozzles 24 4 4 Fuel injection pump 26 4 5 Fuel injection timing 27 4 6 Governor pneumatic 28 4 7 Governor mechanical 31 Governor Model RSV bosch type 34 4 8 Automatic timer 45 4 9 Measurement of engine speed 46 5 Cooling System 48 5 1 Cooling water and radiator 48 5 2 Thermostat 49 5 3 Tension of fan belt 49 6 Electric system 50 6 1 D C Generator 51 6 2 A C Generator 52 6 2 1...

Page 7: ...lace valve guides 70 2 3 Combustion chamber jet and director 70 2 4 Rocker shaft brackets 71 3 Pistons and connecting rods 71 3 How to remove and install piston and connecting rod ass y 71 3 2 How to ceuple piston with connecting rod 72 3 3 How to remove and install piston pins 72 4 Cylinders 73 4 Oversizes 73 4 2 Cylinder liners 73 5 Bearing metals 73 5 General cautions 73 5 2 How to assemble mai...

Page 8: ...cial tools 101 ofAPTER 7 MAIN SPECIFICATIONS AND PERFORMANCE 103 Main specifications of Mitsubishi Diesel Engine Model 40050 103 2 Performance of Mitsubishi Diesel Engine Model 40050 104 40050A for motor vehicles performance curve 105 40050C for construction machine performance curve 106 40050P for general power performance curve 107 ...

Page 9: ...nd make up of components Fig 0 1 Stamped engine No Fig 0 2 Service meter 3 As for fuel engine s power source and lubricating oil to smooth engine operation please use those are above OM class as shown in caution plate Their choice has a considerable influence on the engine s service life Lubrication and other servicing in accordance with the instructions given herein will promise its most satisfac...

Page 10: ...ling 2 Don t run it at high speed 3 Run under some 70 of load at the maximum 2 CHECKUP AND PREPARATIONS PRIOR TO STARTING Prior to starting the day s operations check as follows with the engine placed as level as possible 1 Engine oil level Pull out oil level gauge and wipe then put it in and out again to check oil level Oil level must be above mid point between upper FULL line and lower one If ne...

Page 11: ...ving idle or when air seems to be in fuel system practise bleeding or priming Refer to Bleeding Mechanical governor pneumatic governor Fig 1 2 Around Venturi lever Fig 1 3 Around Stop lever 4 Power source Make sure that battery switch and battery terminals are on Now check as follows and proceed to starting 1 That the engine is clutched off or free from load 2 That stop lever is not in stop positi...

Page 12: ...ting switch 3 Then press button 5 or turn key clockwise to switch on starter When the engine is very cold pull stop lever at the same in opposite direction to position stop and an increase of injection will make starting easier In this case pull it back to neutral as soon as first firing Keep starter running until the engine has completely caught to run with a steady rise of speed but never any lo...

Page 13: ...overning type variation of engine speed depends upon how far Venturi unit is opened for in which position control lever is This design is such that at a certain degree of Venturi unit opening or control lever position engine output is automatically governed with changes of load so as to keep engine speed almost constant During operation leave stop lever in neutral pneumatic governer use For detail...

Page 14: ...ver to neutral Remember that if the lever released when the engine has not yet stopped it may run reverse Note Reverse running of the engine Model 4oQ50 engine may happen though rarely to run reverse in the following cases 1 When in an attempt to cut off injection by pulling back stop lever the lever is released before the engine comes to a dead stop 2 When starting motor is switched on with batte...

Page 15: ...urther increase of fuel feed will cool combustion chamber hence a lag in perfect firing 4 Even when initial ignition has taken place and been followed by imperfect combustion keep starter running until the engine perfectly catches to gather speed so that glow plugs will remain red hot to help perfect firing Starter has a free wheel which protects it against any damage even when its pinion is kept ...

Page 16: ...ut a cover on radiator 9 HANDLING IN THE HOT SEASON 1 Use engine oil intended for summer Refer to Chap 2 Engine Oil 2 Keep the tension of fan belts properly adjusted so as to allow them a slack of 12mm Refer to Par 5 3 Tension of fan belt Chap 3 Watch thermogauge too When cooling water has started boiling from overheat Don t stop the engine at once but let it idling for a time Waiting for water te...

Page 17: ... oxidation By high heat of cylinders oil is subject to oxidate and carbonize and cor sequential collection of carbon and residues leads to wear and seizure Therefore oil needs to contain at least two kinds of additives to improve its stability an anticorrosive and a detergent that dissolves carbon and sludge in oil and thus washers them away From these view points use always H D type that contains...

Page 18: ...facturer of the oil 3 DIAPHRAGM OIL Pneumatic Governor Diaphragm oil is a kind of leather oil intended to prevent the aging or deterioration of sheep skin diaphragm placed in pneumatic governor of fuel injection pump and to keep governor action smooth and sensitive Use always those brands indicated on Lubrication Table and never substitute by engine oil mineral oil 4 COOLING WATER 4 1 Required qua...

Page 19: ... and servicing place the engine as level as possible 1 LUBR ICATION This section covers the points of lubrication which is a basic factor of maintenance It is most desirable to use the classes of oils recommended in the preceeding chapter j Engine oil pan Checkup of oil level 1 Drain plug Fig 3 1 Checking oil level Fig 3 2 Drain plug on oil pan Check it every morning or prior to starting Checking ...

Page 20: ...or 400SOW is 4 7 litres 40OSOC is 6 0 litres 400S0P without oil cooler is 6 7Iittes 2 Fuel injection pump cam case Chockup of Oil level Every 120Hr of run pull oil level gauge 1 out of injection pump cam case and check oil level If it tells a decrease of oil Check and repair the leak Standard oil level is up to the mark line cut on the gauge 1 filter element 3 Head 2 Coyer Fig_ 3 3 Replacing oil f...

Page 21: ...rnor fuel injection pump and governor is forced lubrication by engine oil so it need not check up of oil level 5 Air cleaner with oil bath type Check up of oil level Keep to the optimum oil level in the oil bath Every 60Hr check up of oil level if necessary refill up to 01 L LEVEL Lower level oil is not suf ficient clean action and higher level oil act bad influence to engine Standard quantities o...

Page 22: ...7 Tension pulley Fig 3 7 To apply grease to tension pulley If engine is no need of dynamo tension pulley is equipped Tension pulley has a grease nipple Fig 3 7 every 250Hr of run apply grease to it 14 ...

Page 23: ... 0 v With oil bath E O type Change oil 0 0 0 85 0 tarter Apply oil to E O 0 Several bearing drops Tension pulley Apply oil to G bearing v Note 1 Marks Generally o In very dusty areas First service for new or overhauled engine 2 Symbols E O Engine oil 0 0 Diaphragm oil 3 Mechanical governor is forced lubrication by engine oil 2 AIR SYSTEM 2 1 Air cleaner oil bath type Model 40Q50 engine is equipped...

Page 24: ...influence to the governor action 2 2 Air cleaner Filter paper type In filter paper type air cleaner paper element performs an important part In handling be very careful not to rub or scratch its surface If scratched or damaged even a bit replace with a new element A thin pipe from the case is connected with a vinyl tuve to diaphragm air chamber in pneumatic governor Refer to Par 4 6 Governor Keep ...

Page 25: ...Cleaner case Element Case packing Cleaner cover Wing nut Fig 3 9 Air cleaner filter paper typel 17 II I I ...

Page 26: ... Valve seats are in tight enough contact b Cylinder liners and piston rings are not worn or sticking hard c There is any leak of gas ascribable to other cuases Regular measurement at intervals of about SOOHr of run will provide reliable data to decide when to overhaul the engine 3 Prior to measuring it check and adjust valve clearances so that rockers do not press down valves in compression stroke...

Page 27: ...ry 500Hr of run unfasten oil pan to wash its interior and oil strainer in cleansing oil r n I lr JPiston 1 2 3 4 5 6 7 B 9 10 11 Fig 3 11 Oil circulation diagram 19 ROCker Piston Oil Filter Oil jet Crank Shaft Oil Strainer Rocker arm Rocker shaft Oil alarm Oil pump Injection pump Water pump ...

Page 28: ...t forget to place spring and spring seat where they were 3 Carefully examine used element and oil and if many metallic particularly copper color settlings found which is an evidence of bearing metals being abnormally worm take appropriate measures at once Center bolt Spring Differential alarm terminal Element Fig 3 12 Oil filter 3 3 Differential bypass valve This valve is set in oil filter cover T...

Page 29: ...her an oil pressure gauge or an oil pressure alarm switch which puts alarm lamp alight at a drop below O 5kg cm2 1 Under the following conditions oil pressur often goes out of the given range but will usually become normal as the engine is run a When the engine has not yet warmed up i e soon after its starting In this case oil pressure goes above the standard range claiming for its good warm up th...

Page 30: ...injection rate can be done with stop lever but in other cases should be left to pneumatic governor that works by Venturi negative pressure Fuel injection Pump BiNding plug Fuel fHd pump __ Fuel injection pipe 7 r f F t F 1 injection nozzle FUE RETURN BiNding plug Fuel filter n t i 1 1 LJ L ___ J Fig 3 14 Fuel system diagram 4 1 Fuel filter Overflow pipe 1 Every 120Hr of run screw off bleeding and ...

Page 31: ...l 3 Joint on the side of Bleeding plug filter case is inlet and that on its bot tom is outlet Be careful not to con nect wrong pipes with them Refer to Fuel system diagram 4 In inlet joint of fuel feed pump that connect pipe from fuel tank is placed a strainer to filter off large dust particles Clean it every 120Hr of run If choked with dirt fuel feed will go down 1 Filter cover 2 Gasket 3 Element...

Page 32: ...osened and stop lever in full open position run run the engine scores of revolutions by starting motor and all four injection pipes will be bled of air at a time The bleeding must be done too when the engine has been left idle for a long time fuel pipes replaced or nozzled checked Fig 3 16 Joint on fuel inlet in fuel feed pump Fig 3 17 Bleeding fuel injection pump 4 3 Checkup of nozzles When somet...

Page 33: ...r is pressed hard must form a straight cone of about 40 in spray angle that contains no large fuel particles and must break clean off without leaving any drop of fuel around Fig 3 20 Nozzle spring shim injection orifice In handling nozzles follow the instructions given below 1 Each time to remove nozz les clean off dust from around them in advance lest it should on packings on their tips 2 In leav...

Page 34: ...t should be thoroughly adjusted by means of a pump tester If anything unusual noticed with it have it examined and if necessary serviced by your dealer or at a service shop In such a case that nozzles having nothing wrong at all combustion does not go well in any of cylinders check as follows a With the engine running loosen either cap nut on one injection pipe after another So you will fined the ...

Page 35: ...ting much easier don t c isjoin autotimer from the gear for easier operation in installment Having removed injection pump put caps on delivery valve holders to keep off dust 4 5 Fuel injection timing In this engine injection pump starts injection at a fixed time whatever the injection rate may be Model 40Q50 is attached a mechanical autotimer in option which is coupled with injection pump gear var...

Page 36: ...1 cylinder inlet and exhaust valves keep proper clearance 2 With 1 cylinder piston thus placed at top dead cente read at what crank angle injection will start For this take the following steps 3 Loosen off 1 cylinder injection pipe so that a little fuel remains in the upper part of delivery valve holder Slowly turn crank shaft in its usual direction that is clockwise as viewed from fan and fuel le...

Page 37: ...e or in short turns into negative This negative pressure rises as can be seen in Fig 3 25 with the rise of engine speed and consequently of flow velocity of intake air Through an air pipe it is conducted into negative pressure chamber in diaphragm block to work on diaphragm The governing force it produces is calculated Venturi negative pressure x Diaphragm area Governing force Main sprinC Diff ti ...

Page 38: ...to full load stopper making it to develop max torque If tough torque is required of the engine governor is equipped with a buitin torque spring angleich spring 3 This type of governor requires espeCially perfect air tightness of air pipe and intake system for lack of their air tightness will much affect its performance and cause particularly overrunning Into air chamber for atmospheric pressure in...

Page 39: ...o this spring so it works as angleich Control spring is installed to the adjusting lever s shaft and one end of spring put to the spring seat Control spring force changes by this lever s motion The lower parts of floating lever is combined to supporting lever and this position is determined by full load stopper Sliding peace which is equipped in the middle of the floating lever inserts governor sl...

Page 40: ...rol spring Supporting point B Slip disk Spring seat Angleich spring Governor sleeve Flyweight Full load stopper Supporting lever Stopper Stopper bolt Supporting point A Fig 3 29 RUV governor movement of idling Oil inlet Floatiag lever Bearing bushing 3 Fig 3 29 shows the situation of idling Flyweight though it is lower speed expand to the outside by centrifugal force overcome weak spring force and...

Page 41: ...y this action and reaction Fig 3 30 shows the situation of max ngine speed control Camshaft bushing Stopper bolt Fig 3 30 RUV governor movement of max engine speed control When the engine speed rise from regulation speed by the rapid down of load while the engine running centrifugal force of flyweight overcome the spring force of control spring and flyweights expand to the outside and move the gov...

Page 42: ... bearing The shifter may be moved only longitudinally toward the axis The trunnion of the shifter is inserted in the guide lever which hung by the pin of the governor cover like a bob and prevents the rotation of the shifter A pin is attached to the position slightly above the coupling point of guide lever and shifter with wax The floating lever is attached to either left point or right point of t...

Page 43: ...weight the tension lever will move until its lower end contacts with the adjustable fu I load stopper The revolving axis of the swivel lever is inserted in the governor bush and the center of the lever is slightly eccentric against the spring eye of the tension lever The other end of the governor spring is connected with the knuckle which is attached to the upper end of the boat shaped swivel leve...

Page 44: ...utside by taking off the closing cover of the governor cover as it is designed The ungleich device will amend the full load jet volume of the injection pump within a specified scope according to the set load of the spring which is adjusted by the constant of equipped spring stroke and shim so as to be fit successively for the necessary volume of fuel for engine between the r p m of idling and that...

Page 45: ...ngine increases and its centrifugal foece becomes larger than the spring force the flyweight will spread outside When the r p m decreases the centrifugal foece will decrease and consequently the controlling power of the governor spring will become stronger so that if folds itself inside again The action of the flyweight is transmitted to the control rack through the guide bush shifter and link And...

Page 46: ...ver will be separated from the guide lever and the governor spring which is connected with the tension lever is stretched This governor spring pulls the tension lever to the place of full load stopper Then the shifter and the guide bush act on the left side and the weak start spring will move the floating lever so as to transfer the control rack of the injection pump to the starting point beyond t...

Page 47: ...ccordingly the force of the governor spring which acts on the shifter guide bush and flyweight through the tension lever becomes very weak and the flyweight may spread outside even at a low speed r p m Full Idling Cantral lever FuII load stopper Fig 5 Idling The flyweight transfers the guide bush and the shifter following the direction of the arrow as shown in Fig 5 The guide lever connected with ...

Page 48: ... will maintain the adjustment of rotation within the limit which is fixed by the changing rate Let it be supposed that a driver moves the control lever from the idling position to a position where the proper speed will be obtained through the link by working the pedals Fig 6 in this case The tension of the governor spring and the moment arm concerning the revolving center of the tension lever are ...

Page 49: ...tion of fuel decrease The r_p m of the engine will not rise from this point and it is maintained by the governor under a fixed condition When the control lever is transferred to the position of the highest r p m Fig 7 the governor works as shown in the Fig 6 as aforesaid_ Fun load JdU Starling af Ungleich S P G_ernal SDrina Cantrol lever t r I 1i uuide lever Tension lever Fig_ 7 The highest revolv...

Page 50: ...ull load the work of ungleich ends Control lever ln9l1IlCh spr ing Fig 8 Starting of the highest r p m control Full load No load idle sub sprikg Fig 9 The case as controlled at the non load condition 42 ...

Page 51: ...nst engine cylinder per each stroke adopting the r p m as parameter The of A 1 1 Nl p m of En9ne N2 Fig 10 fuel jetting volume curve in the same figure is shown at the full load position of the control rack by adopting the fuel jet volume which is supplied by the injection pump per each stroke as function This fuel demanding curve shall be made similar to the fuel outlet curve within the limit of ...

Page 52: ... of full load 5 Stoppage of engine An engine having a governor without a stop device will be stopped by transferring control lever of the governor to STOP regardless of the position of the flyweight Slightly before the control lever reaches STOP or before the knuckle come in touch with the topper bolt the boss of the swivel lever will push the guide lever and transfer the control rack of the injec...

Page 53: ...ion timing The design is such that automatically puts ahead the injection timing with a rise of the engine speed and regards the injection with its drop Fig 3 32 shows the timer in disassembled condition Each of two flyweights has a hole by which it is supported on flyweight holder On it is made a curved surface designed to help it develop the required efficiency Bearing pins fixed on the holder h...

Page 54: ...he engine is designed to remain constant So the lift pulls bearing pin A over the distance E which results in turning the pump camshaft on the driving shaft so as to put ahead the injection timing A ATA STANDSTILL B AT MAX SPEED Fig 3 33 Timer flyweight The timer for Model 4DQ50 Engine is intended for clockwise revolution and provides a max angle of lead of eO as measured on the pump camshaft At a...

Page 55: ...odel 4DQ50 engines intended for motor vehicles and construction machines non load max speed is 5 10 over the rated speed 4 How to measure engine speed In case of hourmeter equipment with engine pick up the hourmeter and equip a special parts Fig 3 34 and measured by tachometer In this case tachometer indicates 1 2 engine r p m 30498 01100 30498 01000 30425 325 Camshaft Oil pump dri ve shaft Fig 3 ...

Page 56: ... run into radiator to be cooled there by air blasts from fan and at the same time close bypass hose Thermostat case on cylinder head has two bosses one covering hole to fit in thermostat and the other water outlet for car heater 5 1 Cooling water and radiator 1 For checkup of water level refer to Checkup and preparations prior to starting 2 In order to remove scale and dust in radiator and engine ...

Page 57: ...d fan working well the probable cause is that thermostat has got stuck up and remains close If on the contrary long oreration should not raise water temperature up to the optimum level 75 85 Cl thermostat is suspected to remain open from puncture In either case check it and take necessary measures Thermostat is designed to start opening at 76 C and fully open at 90 C under atmospheric pressure Con...

Page 58: ...PRESSIJlE I _ _ INDICATOR STARTER 12V 2KW BATTERY 12V JOOAH H 0 OFF 0 ON 0 S 0 _ 40mm 5 rnnI a8smnl Fig 3 37 Diagram of electric wiring in case of AC dynamo 0 0 0 IJf tL Q D FUSE BOX OIL I RESSURE INDiCATOR _______ 8 H 0 m 0 ON 0 _ 40mni _ 5mm1 o esmnl Fig 3 38 Diagram of electric wiring in case of DC dynamo 50 G G S 0 0 0 0 M 0 ...

Page 59: ...llow the service hints given herein in addition to those in lubrication Table will maintain the electric system trouble free Prior to making any service be sure to turn off battery switch 6 1 D C Generator This generator is a D C shung wound type whose main components are field coil armature and brushes 1 Check for wrong wiring and loose terminals Brush Ball bearing 2 Inspect brushes at times re t...

Page 60: ...ispenses with commutators and subjects the brushes only to a small current while its field has very simple make up as compared with the armature of a D C generator and it is free frpm the need of commutation The construction of the A C generator is illustrated in Fig 3 42 Revolution of the field generates a three phse alternating current in the armature which is rectified by silicon diodes install...

Page 61: ... precise instruments If gone wrong have it serviced at a specialized service shop without breaking the seal 6 2 2 A C Generator Relay Relay The relay is a point action type that regulates the field current by closing and opening the contact points so as to control the generator output 6 3 Starter The starter is a D C compound motor of so called pinion shift type where pinion is shifted by magnet s...

Page 62: ...ed water If electrolyte spilled out of cells which does not involve an increase of its specific gravity add dilute sulphuric acid of 1 280 in specific gravity at 20 C 2 To see how much battery is discharged measure the specific gravity of its electrolyte The following table shows the relation between the degrees of discharge and hydrometer readings at 20 C Degree of Totally 3 4 1 2 1 4 Completely ...

Page 63: ...s accident to say nothing of early break down of battery nor bring naked fire near it 7 RE SCREWING OF MAIN BOLTS With initial fatigue of gaskets and packings in newly assembled engine and with its long use bolts will get loose To prevent accidents ariSing therefrom check main bolts at regular intervals to see if they are working tight enough and if loose screw again accofdingly Apart from this al...

Page 64: ...ut uni formly then tight according to the illustration 14 12 o 0 2 10 11 o 0 Notes 1 Numbers show bolt screwing order 2 Camping torque 12 0 kg m 861b ft Fig 3 43 Order to screw bolt on cylinder head 7 2 Main Bearing caps and connecting rod caps Each time to wash oil pan and strainer check bolts on main bearing caps and connecting rod caps and if loose screw them tight again 7 3 Others Keep the fol...

Page 65: ...sure measure 0 0 At the same time to Replace element 0 change oil or when bypass alarm lamp E Oil filter got alight Wash inside of case Of 5 Oil pan Wash inside and strainer C Drain off water and 0 Fuel filter sediment Replace element 0 Fuel feed Clean inlet joint strainer 0 pump E Check injection pressure C 120 Skg cm 0 Injection and spray nozzles Of a Remove carbon from 0 nozzle seat packings Ch...

Page 66: ...d commutator Starter Dismount to check pinion clutch Check electrolyte and refill level 0 Battery Measure specific gravity of electrolyte 0 Main bolts Screw again Notes o General o In very dusty areas First servicing for new engine or after overhauling o Services to be made by your dealer or a service shop 58 500Hr 0 0 C 0 0 OOOH Remarks 0 0 to Usually once in two weeks but once a week in summer S...

Page 67: ...the inside of the engine or with fuel injection pump ask your dealer or a service shop for necessary repairs Whenever any trouble noticed put on record its detailed descriptions and the odometer reading on that day In disassembling to research into the cause of trouble and repairs take necessary measures to keep off dust and arrange removed parts so as not to miss any of them as well as to permit ...

Page 68: ... injection pump seals lDsufficic Dt injection 0 0 0 quantity Excessive iJljection quantity 0 Improper fuel spray rom 0 0 0 0 0 0 0 0 injection nozzles e Excessive fuel return from 0 0 0 0 injection nozzles ction timias coo 0 0 0 0 OU1ced Injection timias coo retarded 0 0 0 0 0 0 Defective autOmatic timer 0 0 0 0 0 De ec tiw gowmot control spring l IaIadjusted goWlrDOr 0 0 damper sprins Engine spee...

Page 69: ...0 I I 0 0 0 I I I I I I I f h l l r E j Bnglne vibrates excessively Bngine staUs Poor response for deceleration Bngine does not pick up apeed Bngine operates at hlSh speeds but faUs to stop Bnglne turna over In reverse direction Bxcesslve fuel consumption Bxcesolve oU consumption OU Is dUuted by fuel Water In oU Blow by When enr ne stopS jg warnins amp does not come on Wornlng lamg comes on B at l...

Page 70: ...0 0 0 0 0 0 00 Too much ex i It i haust smoke it Ii 0 o 0 00 o 0 o 00 00 0 o 0 0 0 I 0 o 0 o I Stutlnll motor does nol turn over sufficlontly to Clank enslne Enslne can be I cranked manually 0 l Enslne cannot bo ai It cranked manuaUy it IHeator plugs do not glow red IHeator plugs glow red too ouly f J I I I I I I I A Uttlo oxhaust smoke r 0 0 0 0 0 1 I 0 0 I 00 0 0 0 I I I o 0 0 0 0 0 I o I 0 0 0 ...

Page 71: ... 0 0 0 0 0 0 etighten and replace gasket if necessary 0 Replace crankcase 0 Check f r connections and repair If necessary replace part s Repair and replace if necessary Repair and replace if necessary Repair and replace starting motor if necessary Repair or lace niDg gear Replace pwon 0 0 0 Reclwge or replace battery If necessary heat it Replace part s eplace oop r pac cing s and if necessary eate...

Page 72: ... Jammed tappets Replace tappets Worn plungers ReplaCe plungers Worn tappet cams Replace tappet cams Worn bearinp Replace bearinp Worn or broken plunger sprinp Replace plunger springs Loose pllmger pinions Reinstall properly by matching stamped marks Defective delivery valves Replace valves Worn or broken delivery valve Replace valve spring springs Insufficient injection quantity Governor stop leve...

Page 73: ...2 l706 4 71 l Ib in2 on nozzle tester by inserting shim s Carbon deposited on packings Remove carbon at nozzle tips Injection timing too advanced Improper installation of fuel Re time properly by tilting injection Injection pump pump toward engine Incorrect installation of timing Re time timing gear train gears Injection timing to retarded Improper installation of fuel Re time properly by tilting ...

Page 74: ... Overhaul engine if oil laden gases load are exhausted Insufficient m Clogged air cleaner Clean and replace element if paper element type necessary Clogged air cleaner Wash interior Oil bath type Clogged intake manifold Check and clean Poor compression Defective valve seats Repajr Sticking valve stems Repm and replace valve stems if necessary Failure of rocker arms to Adjust valve clearance to 0 3...

Page 75: ...ain plug or hose clamp Rust and scale deposited in Flush radiator Dust and dirt around radiator Flush Slippage of fan belt Adjust belt tension Inoperative thermostat Replace kept closed Radiator dissipates heat Extremely low atmospheric excessively temperature Uncovered radiator Cover radiator Inoperative thermostat Replace part s kept open Jammed moving parts Sticking cylinders pistons RepaU and ...

Page 76: ... 68 ...

Page 77: ...ing apart the main parts such as pistons connecting rod valves and metals arrange then or put numbers on them in an appropriate way to place them later where they were Remember particularly that caps on connecting rod and main bearings being machined in pairs with respective bodies cannot be replaced separately 3 When the engine overhauled make every service specified in Retular Checkup and Servic...

Page 78: ... valve seat insert be fitted in ask your dealer or a service shop for the service If valve face scratched or worn replace with a new seat so far as available It can however be ground until margin becomes 1 2mm 2 2 How to replace valve guides To remove valve guide press it down with remover while to fit in a new guide use installer so as to set it with the top end 18mm above the surface of cylinder...

Page 79: ...it down screw those bolts in reverse order that is first long bolt 1 and then short ones 2 In setting brackets allot enough clearances to permit both left and right rockers to move smoothly Fig 5 4 Setting direction of combustion chamber jet and director Fig 5 5 Bolts on rocker shaft bracket PISTONS AND CONNECTING RODS 3 How to remove and install piston and connecting rod assy In Model 4DQ50 Engin...

Page 80: ... 2 No 3 and No 4 according to their arrangement as seen from timing tear case How to couple together each pair and to set in cylinder crank case is illustrated on the right 3 3 How to remove and install piston pins Fitting of piston pin is such that does not permit it to be pressed in by hand at normal temperature So warm up piston in boiling water to expand the inner diam of piston pin hole then ...

Page 81: ...size In Model 40050 Engine cylinders being cast in one body with crankcase have dry liners When they have got worn more than O 2mm in bore or cut deeply in lines machine them to a suitable oversize Oversize pistons and piston rings are available in three sizes 0 25 0 50 and 0 15 4 2 Cylinder liners If oversize parts are not available or when they have got worn over the limit of use 1 20mm change c...

Page 82: ...r of the pair can be assembled upon the other 5 3 Undersizes To both main bearings and connecting rod bearings metals must be renewed when their clearances exceeded O 2mm When replacement of metals not considered to produce satisfactory results because of crank shaft being unevenly worn or streaked deep grind it so much as to fit to any of undersize metals which are available in three sizes 0 25 0...

Page 83: ...h the trouble of checking valve timing For reference sake however valve timing diagram is given in Fig 5 11 Every cam having a symmetrical profile checkup of valve timing requires to measure crank angle at max cam lift to see if it equal to the angle indicated with broken line in Fig 5 11 The procedure is detailed as follows Take for instance No 1 cylinder inlet and exhaust valves First set valve ...

Page 84: ...ont end oil seal has concentricallY machined periphery Center the seal so as to fit to it Meanwhile for rear end oil seal center it on basis of its periphery In either case a special centering tool is available Remember that rear end oil seal must be set with oil leak off knotch in slinger down Prior to installing oil seals coat their lips with pure engine oil 8 MOUNTINGS On motor vehicle rubber c...

Page 85: ...ends of side packings cork plates and fit semi circular rubber packings in the grooves To apply liquid packing to corner intersections will prove very effective in preventing leakage Coat semi circular rubber packings with oil on the surface so that oil pan edges will slide easily on Finally screw bolts 4 pieces each in front and rear uniformly in order not to strain packings 10 OIL PUMP Fig 5 13 ...

Page 86: ... main bolts the necessary instructions were already given in Sect 7 Re screwing of Main Bolts Chap 3 The other bolts should be screwed with reference to the following table Nominal Thread mm 6 8 10 10 12 Pitch mm 1 1 25 1 25 1 5 1 25 Plated Kgm 0 9 2 1 4 3 4 0 7 4 ft Ib 6 5 15 31 29 54 Clamping kgm 0 7 1 4 3 0 2 8 5 2 Not plated ft Ib 5 0 10 22 20 38 2 Prior to screwing the following bolts coat th...

Page 87: ...gs Gaskets Cylinder head Copper asbestos Three Bonds No 201 Front plates Rubber asbestos No 2 Timing gear case No 2 Timing cover No 2 Oil pan sides Rubber cork No 2 Oil pan ends Rubber Atomosit Oil filters Rubber asbestos Three Bonds No 2 79 ...

Page 88: ... ino O emz General I c CD e 3 6 Valve timing 0 crank angle I 7 Injection star ing e igh 10 erank tlmUlg angle 1 II Bore 84 tP 0 035 0 Cyl inder 8 0 20 II out of round ess than 0 015 0 bore Taper ess than 0 015 n Top I 9 Strain Less than 0 05 0 2 o surface Projection of pistons o 3 N O 75 10 abO ie cyl inder crank case top surface Periphery 111 Outer diam 83 46P 0 2 Top 2 0 020 0 040 0 Rings and Wi...

Page 89: ... ODe 4 cyliDCIer to equal er naninaldiam of COlI and use oversize pistons and ri size Change of 1iners is _ _________ j r n be yo iId l i m i t ct us el iic e desecribed s aratel Ijnen Be grini to minimmn required 0 15 0 10 0 10 Piston pins 0 05 Check bearirv clearcmces UseCoversize pistons accordi tg to 01 8 OVersize Q 25 HI 50 aDCI 0 75 Till worn up to limit of use pistons replacing rings once l...

Page 90: ...uge ern 22 Width 35 0 15 0 35 0 50 e J ca til lIII Inner and outer diams Metals Journals and 65 0 030 Q 089 general II 23 0 and stan iard clearances 0 20 main bearings 24 j l widJfh o l 3 7 0 1 0 189 0 30 In rinsz Wl t 25 t cFteraf lPPOr t at QUrn s Less thann02 0 05 Gi 26 Axial runout at rear end Less than 0 1 G l it IHot rface 27 Strain Less than 0 15 0 2 28 Icse r 03te diams a st r c earance 13...

Page 91: ...size 1 Use crankcases arxI bearing 0 0 0 and 0 7 T i11 worn up to 1Lmi t of repair caps in a set replace metals once limit 2 Place metal with thrust over 1ll e er ze metals bearing at top Urxlersue 0 2 0 50 and 0 75 3 Of each pair of metals lac g inl ri wi th place that which has oi 1 hoh ust nn pOD the other Repair bend or replace Measure as set in crankcase Re grind to minimum required If10ver t...

Page 92: ... Inner diam IAfi1 541 i 04 0 09 43 installed Ab 2 0 15 Journals 1 3 53 r rust elates ca 44 Width 5 0 05 0 112 0 3 ret lners Cam profile 45 Longitudinal diam 5 944 8J 0 46 Runout of center wi th 0 02 0 05 end beari11lls fixed Ildler bush 47 Inner and outer diams 36 l25 Q 07 0 1 and idler shaft ani standard clearance S Imtrui er f r0 OS O 15 48 Width 26 0 35 flog fJMi8Fd Inner diam shaft outer 0 49 ...

Page 93: ... lISt valves Can be measured in warm engine if Engine is uniform temper ature 0 10 If not over I imi t of repair replace tappets In setting give even play in rocker shaft direction If over I imi t of repa ir replace busbes ream if nec essary Replace thrust plates D1 D2 6 84 mhO D 6 S Replace bush Replace thrust plate Replace gears ltepair case cover or case f sur ace 0 15 Replace case 1 0 Replace ...

Page 94: ... 0 5 1 59 Hight in free H 23 4 1 Co Unit seals 60 Projection of earbon A 1 5 61 Valve openinl 76 5 C 2oC Thermostat teIq er ture 90CC 2OC Full q enlng temperatUI l e Valve lift t 62 9mm 0 0 0 L Fan belt 63 Tension A 20mm 12mm Approx 250mnAq Resistance 50mmAq negative at I r higher Ai r cl ealler pressure 3 000 at 3 000 r p m r p m J filter paper 64 type Approx 250 mmAq 120mmA at 3 000 I at 3 OOC r...

Page 95: ... thickness of If hitting replace impeller and bearing 23 5 Replace unit seal ass y C 0 at atmospheric pressure to Usually press with a finger Shifting generator adjust _ tip wi th adj ust ing plate V Clean or replace eleEneDt Nectiv P su take off port r OJ cQJj Adjust with shims t 1 eoat with tal c nl 87 ...

Page 96: ... test ass y Leak from between re h rod and hous i c than c In Less than 25 not more Priming punp 76 Suction capacity than 30 strokes strokes Shorter than nOt more Pump body 77 Suction capacity 45 sec than E 50 sec 41 ell 78 Delivery pressure 8 2 kg Ditto left til cmz Q 79 Del ivery rate More n OOc c lTlin S 900c in Oam shaft 80 Longi tyd inaI Aiam 32 0 0 1 of Drofde 41 Bearings 81 2 Oam shaft play...

Page 97: ...2 Overall pIa less than O 0 075 Ditto left With discharge port plugged up apply 2Iqv cm of air pressure then put whole PIJI11 in gas oi1 Moving priming pump handle at about 60 strokes per min see how many strokes required to f4ar yi acharging Suction ad m Rtmning injection Pimp at 150 r p olD see how much time required for feed pump to start discharginlZ Di tto left Measure at full di scharge wi t...

Page 98: ...Oi I t ightness e c Del ivery 0 va Ives GO 96 Spring free length 32 0 5 c s 1 0 Injection starting 97 90 0 30 intervals 98 Lift to start injectio 1 95 0 05 with rack at 21mn position Pump Rack Injection Unevenness Speed Position Rate DJDYrev r pro Gun mzV rev cyl cyl Adjustment of injection 99 rates 2 000 8 5 36 39 3 1 000 8 5 36 39 2 1 000 8 0 32 35 2 200 6 0 10 16 2 Diaphragm 100 Air t ightness ...

Page 99: ... than 5 sec Replace delivery valve ass Y at1S0k anzand bring control rack to non injection position Com to see how soon it will drop 10k em If it takes 1 longer than 5 sec oil tight ness is satisfactory Tappet clearance more than 3 Conditions Nozzle tips ND DN40SDND32 Making it inject into open air on injection pamp tester Injection pipes 1 6 600 Injection pressure 120 k cmz De I ivery pressure 2 ...

Page 100: ... O Skg 15 0 I Terminal Generator S Q Vol tage Current Rpeed Non load bel_2 100 14V characteristics OA r p m u 113 Performance below 2 600j Load 14 M 14V cbar lcterist ics r p m i u Cl 12 01 t 1450 1650 IiQ iMltor ing test battery I 7 6 5A r p m 114 Point gap 0 4 0 6 Charge switch 115 Air gap 0 7 0 8 relay 116 Rwi tch in vol tage 13 14V 117 fM i tch of f voltage above 8 2V Constant 118 Air gap 1 05...

Page 101: ...ec tion rate 38mmYrev c yl loose 1Error in intermediate angles between 2 5 0 at 750 r p m and 8 5 0 at 2 OOOr p m must be Ie s than 0 75CC 30668 30100 DP200 12Z R Relay for joint use 30668 2620cr RJi200 12 3591 11 0 5 thic k and 20 wide Crank pulley pitc h dimn 12091 Generator pulley pitc h diam 7191 Revolution ratio 1 69 Charge alarm lamp gets alight below 880r p m of engine speed Switc hed on 93...

Page 102: ...ulator Back rap 0 8 1 1 Non load vol tare 4 D 15 5V regulation at 4 000r p m Air rap 0 9 1 2 BazIp relay Point rap 0 75 1 1 Back gap II 0 75 1 1 Switch Involtage O O Slri tch offvo l l 2 c n tatltr sillehraclet outer diam Inner diam 14 2 11 05o 0 2 and standard clear u e 0 098 CN Shaft and Oppos i te bracke t ou ter f o 030 dian inner dian and 12 21 1 0 2 II standard clearance 0 070 bncket Pinion ...

Page 103: ...Limi t of Use Remed ies Remarks _ 3D666 231D8 MO 1 SB 10072 95 ...

Page 104: ...voltage with 132 6 5 10V pin ion locked II 133 Axial gap to r iDg gear 3 1 cr Terminal Current V ol tage 134 Per formance Non load below runniag speed 11 3V BOA Load 10 V 200A d1z Cteristics Binding 6 5V above torque SOOA Proat metal inner di_ shaft diam 0 030 anel s t 3Ilelard 12 2 6 0 2 clearance 0 076 I Bear metal iUDer Shaft and diam shaft diam 14 2 6 0 050 Brackets and s t anelard 0 09B 0 2 c...

Page 105: ...Limi t of Use Remedies Remarks 41 10 6 5 thick and 19 wide Starter Speed Torque above 3 000 r p m 1900 rpm 0 ftlre thal Skarn 41 13 1 5 1 s okg 97 ...

Page 106: ... Set ting ILimi t of St andard I r p Pr i jTenninal Current Starter Vol tage speed Torque Perb Non load I 23 V I below above mance rUDJIiDg speed SOA 4000 rpm Load 9V below more characteri st i CI 700 A than 3 1 ksrm SWI tCh in vol tage below 16 V 98 ...

Page 107: ...Limit of Use Remedies Remarks 99 ...

Page 108: ...31391 12500 To screw glow plugs 3 Handle 12 x 250 30091 01900 For above tools 1 2 4 Thickness gauge 03714 63000 To check and adjust valve clearance 5 Cranking handle 30691 11800 To turn crank shaft Other ordinary tools such as mentioned below will be necessary too CD Double end wrenches spanners 8 26 Adjustable wrench monkey spanner 10 Pliers Screw driver 150 Fig_ 6 1 Common Tools 100 ...

Page 109: ...val 8 31391 10600 Valve guide installer 1 Valve guide installation 9 31391 10500 Valve guide remover 1 Valve guide removal 10 31391 12300 Rod 1 Use t01 c her with 8 31391 10600 11 30691 11800 Cranking handle 1 Engine cranking 12 30891 02400 Idler shaft puller 1 Idler shaft removal 13 30091 01101 Extension univeISal 1 Injection pump installation 14 30091 07300 Idler bushing puller I Idler bushing r...

Page 110: ...Fig 6 2 Special tools 102 ...

Page 111: ...tion system Forced lubrication Oil pump Trochoid pump Oil filter Full flow type with filter paper element Cooling system Forced circulation of cooling water Water pump Centrifugal pump Thermostat Wax type Fuel system Fuel injection pump Fuel injection nozzles Governor Autotimer option Fuel filter Air cleaner Electric system Starter Glow plugs Bosch type Model PES4A65B Bosch type Model DN40SD Pneum...

Page 112: ...ut HP rpm 66 3 800 The above performances exclude automobile and water craft use are under standard conditions atmospheric pressure 760 mmHg Temperature 20 C Humidity 65 max output is under condition with 760 mmHg pres 15 C temp Performance tests in relation to the above are being carried out in compliance will JIS specifications In relation to applying to generators and general power plants conti...

Page 113: ...0A Engine for Motor Vehicles Equipped with fan air cleaner and generator not loaded Air temperature IS C atmospheric pressure 760mmHg relative humidity 0 4DQ50A L V V 1 V V L 1 j V i 1000 1500 2000 2500 3000 3500 3800 Engine Speed r p 1n 105 14 i 13 oX 12 a ll 220 200 180 ...

Page 114: ...ruction Machine Equipped with fan air cleaner and generator not loaded Air temperature 20 C atmospheric pressure 760mmHg relative humidity 65 4DQ5OC 1 L 1 V 1 1 II V 1000 1500 2000 2500 3000 Engine Speed r p in 106 13 E 12 0 11 10 o I 230 210 190 c o a E I I C o Q I U ...

Page 115: ...e for General Power Equipped with fan air cleaner and generator not loaded Air temperature 20 b atmospheric pressure 760mmHg relative humidity 65 4DQ50P II 1 1 I I 1000 1500 2000 2500 3000 Engine Speed r p m 107 13 E 12 11 CD 10 210 190 o t II e Q c 0 Q E I II C 0 u Gi I u ...

Page 116: ...99609 50000 ...

Search results

Summary of Contents for 4DQ50

Reviews:

Related manuals for 4DQ50

Brands by name

Popular brands

Mitsubishi 4DQ50, Service Manual

Search results

Summary of Contents for 4DQ50

Reviews:

Related manuals for 4DQ50

Brands by name

Popular brands