Engines KAMA3-740.50-360, KAMA3-740.51-320, designed for installation on single vehicles and truck tractors used as part of road trains, supplied to the domestic market and for export to countries with a temperate and tropical climate, as well as supplied to spare parts
Motors manufactured in version "U" in accordance with GOST 15150-69 are designed for operation at ambient temperatures from minus 45 to plus 40 °С, relative air humidity up to 75% at a temperature of 15 °С and in areas located on altitude up to 3000 m above sea level with a decrease in power, economic and other indicators up to 20%, with overcoming passes up to 4500 m.
Motors manufactured in version "T" in accordance with GOST 15150-69 are designed for operation at ambient temperatures from minus 10 to plus 45 °С, relative air humidity up to 80% at a temperature of 27 °С and in areas located on altitude up to 3000 m above sea level with a decrease in power, economic and other indicators up to 20%, with overcoming passes up to 4500 m.
General view, longitudinal and transverse sections of the engines are shown in Figures 1-5.
Compression-ignition, liquid-cooled, four-stroke, eight-cylinder V-engines, turbocharged and air-to-air intercooled (CAC).
The engines 740.50-360 and 740.51-320 comply with the requirements of the UNECE regulations (EURO-2) in terms of emissions of harmful substances with exhaust gases.
The base part of the engines is the cylinder block, on which the units and parts of the engine are installed and fixed. Wet-type cylinder liners are installed in the boring, semi-blocks
The top of the cylinder liners are covered with heads, separate for each cylinder. From below, the cylinder block is closed by a stamped oil sump.
The camshaft is located in the cylinder block on five plain bearings. The crankshaft is installed at the bottom of the block.
The engine cooling system is liquid, closed type, designed for the use of low-freezing coolant.
Technical characteristics of the engine 740.50-360, 740.51-320
Parameter name - Value
Engine type - Four-stroke, compression ignition
Cylinder arrangement - V-shaped, 90° camber
Cylinder firing order - 1-5-4-2-6-3-7-8
The direction of rotation of the crankshaft is right (counterclockwise, as viewed from the flywheel side)
Cylinder diameter and piston stroke, mm: 120x130
Displacement, l: 11.76
Rated power, kW (hp): 265 (360); for engine 740.51-320: 235 (320)
Maximum torque, Nm (kgf m): 1470(150); for engine 740.51-320: 1275 (130)
Setting fuel injection advance angle, deg: 9+1
Compression ratio 16.8 (±2)
Crankshaft speed, min-1:
- - nominal 2200±50
- - at maximum torque 1300-1500
idling:
- - minimum 600±20
- - maximum 2530-80
Number of valves in the cylinder head - 2 (inlet and outlet)
Clearances on a cold engine, between rocker arms and valve stems:
- - inlet - 0.25...0.30 mm;
- - graduation - 0.35...0.40 mm.
Oil pressure in a warm engine at crankshaft speed, kPa (kgf/cm2):
- - nominal 392...539 (4...5.5)
- - minimum idle speed, not less than 98 (1)
Nozzle, type - 273
Models 273.1112010-20 (273-20)
Atomizer manufactured by YAZDA, model 273.1112010-20 or 273.1112010-50 (273-50)
or models
Atomizer manufactured by f. BOSCH DLLA 148 S 1380
Injector injection start pressure, MPa (kgf/cm2): 23.73...24.90 (242...254)
High pressure fuel pump (TNVD) model 337-20.04; for engine 740.51-320: 337-20.03
The pressurization system is a gas turbine with two turbochargers and an air-to-air ONV.
Generator model G-273V or 6582.3701 (in accordance with the design documentation) - three-phase synchronous, alternating current, with built-in rectifier unit
Generator G-273V:
- - rated current, A; 28
- - rated rectified voltage, V; 28
- - rated power, kW. 0.8
Mod generator. 6582.3701:
- - rated current, A; 75
- - rated rectified voltage, V: 28
- - rated power, kW. - 2.0
Starter 5662.3708 DC, series excitation, with electromagnetic drive
- rated power, kW 8.2
Model 161 gearbox manual, eight-speed;
or
The gearbox model ZF-16S151 of ZAHNRADFABRIK company is mechanical, sixteen-speed, includes a main four-speed gearbox with a built-in two-stage divider located in front of the main gearbox and with a two-stage planetary demultiplier located behind the main gearbox.
Possible malfunctions and solutions
Fault
- Cause of malfunction
Remedy
Engine
Engine wont start
- Lack of fuel in the tank
Fill the fuel tank, bleed the fuel system.
- The presence of air in the fuel supply system
Fix leaks, bleed the system.
- Violation of the adjustment of the fuel injection advance angle
Adjust angle.
- Freezing of water that has fallen into the fuel pipes or on the grid of the fuel tank intake
Carefully heat the fuel filters, pipes and tank with a rag soaked in hot water or steam, do not use an open flame for heating
The engine does not develop the necessary power, it is unstable, smoke during its operation
- Clogged air cleaner or air intake hood
Maintain air cleaner or clean hood screen
- Insufficient fuel supply
Replace the elements of the fine fuel filter, wash the coarse filter, tighten the connections in the fuel pipes.
- Violation of the adjustment of the fuel injection advance angle
Adjust angle.
- Clogging of the nozzle (coking of the sprayer holes, freezing of the needle) or violation of its adjustment.
Rinse the nozzle, replace the atomizer if necessary, check and adjust if necessary.
- Violation of the adjustment of the regulator control lever drive (the control lever does not reach the bolt for limiting the maximum crankshaft speed).
Check and adjust the governor drive.
- Breakage of the injection pump pusher spring.
Replace the spring and adjust the pump on the stand.
- The ingress of dirt between the seat and the valve of the fuel priming pump or the breakage of the spring.
Rinse the valve or replace the spring, test the pump on the stand.
- Violation of the tightness of the injection valves of the high-pressure fuel pump or breakage of the spring.
Repair valve leakage at workshop or replace spring.
- Jamming of the plunger of the injection pump section
Replace the plunger pair and adjust the pump.
- Violation of the adjustment of thermal gaps in the gas distribution mechanism.
Adjust gaps.
- Depressurization of the membrane cavity or damage to the membrane of the corrector for charge air pressure.
Restore the tightness of the membrane cavity or replace the damaged membrane.
- Stopping the oil supply to the charge air pressure corrector.
Restore oil supply to corrector.
- Loose fastening or breakage of the high pressure tube.
Tighten the fastening nut or replace the tube.
- Poor compression due to malfunctions of the piston group or loose fit of the gas distribution valves to the seats.
Check the condition of the pistons and piston rings, grind the valves.
- Fuel thickening (during the cold period).
Replace the elements of the fine fuel filter, replace the fuel with the appropriate one for the season, bleed the fuel supply system.
Low charge air pressure:
- leak and air through the intake manifold connections with cylinder heads, nozzles, turbochargers and compressor;
Tighten connections, if necessary, replace gaskets and connecting hoses.
- gas breakthrough in the connections of the exhaust manifold and the turbine housing;
Tighten connections, replace gaskets if necessary.
- turbocharger rotor sticking;
Replace turbocharger.
- pollution of the exhaust tract, flow parts of the compressor and turbine.
Clean the pipelines, remove the turbocharger, and remove deposits from the flow parts.
Extraneous noise in turbocharger
- Rotor hitting against body parts
Tighten the bolts securing the turbine and compressor housings. Check that the rotor is not touched at its extreme positions. If the rotor hits, replace the turbocharger. If the noise persists, remove the turbocharger for maintenance.
High frequency noise (whistling)
- The tightness of the intake and exhaust ducts of the engine is broken
Tighten the bolts and nuts securing the system parts, if necessary, replace the gaskets.
Increased oil consumption
- Prolonged engine idling.
Dont idle the engine unnecessarily.
- Oil leakage through the connections in the turbocharger lubrication system.
Tighten connections, if necessary, replace seals and rubber sleeves.
- Deterioration of the valve-sleeve interface in the cylinder head, aging of the rubber cuff of the valve.
Check and replace worn parts.
- Clogged air cleaner or air intake hood.
Maintain the air cleaner and clean the hood mesh.
Reducing oil pressure in the lubrication system
- Low oil level in the oil sump.
Check and, if necessary, add oil to the "B" mark.
- Malfunction of pressure control devices
Make sure the devices are working.
- Use of oil of the wrong viscosity
Change the oil to the appropriate chemotological map.
- Dirty oil filter elements
Replace filter elements.
- Violation of adjustment or jamming of the safety valve or valve of the lubrication system
Check valves and eliminate jamming, adjust or replace faulty parts if necessary.
- Clogged oil pump intake
Rinse the intake.
- Coolant getting into oil
Check the tightness of the water chamber, the seal of the cylinder liners, the tightness of the oil-water heat exchanger, replace the defective parts.
- Oil leaks at the joints and oil lines of the lubrication system
Check the condition of technological plugs, plugs, tightness of fasteners at the joints, the condition of sealing rings and gaskets.
- Violation of the oil pump
Remove the pump and check its operation on a special stand.
- Inadmissible increase in clearance in the bearings of the crankshaft and camshaft
Repair the engine.
Emergency oil temperature indicator lights up
- Malfunction of emergency oil temperature sensor
Make sure the sensor is working, replace if necessary.
- Sticking of the thermal valve for turning on the heat exchanger, malfunction of the thermal force sensor
Check the operation of the heat exchanger thermal valve, if necessary, remove jamming or replace the sensor.
- Clogged pipes or dirty cooling plates
Check the oil/water heat exchanger for clogged tubes and dirty cooling plates, flush or replace the heat exchanger if necessary.
Increasing oil pressure in the lubrication system
- High oil viscosity.
Change the oil to the appropriate chemotological map.
- Violation of the tightness of the control signal line connecting the main oil line with the pump or its clogging
Check the oil supply pipe to the pump, tightening of the fastening bolts, the presence of a hole in the cover.
- Jamming or misadjustment of the lubrication system valve.
Check valve and remove jamming, replace faulty parts if necessary.
Engine knock
- Early injection of fuel into the cylinders.
Adjust fuel injection advance angle.
- Increased thermal gaps in the gas distribution mechanism
Adjust gaps.
- Wedging of the valves of the gas distribution mechanism in the bushings (the piston touches the valve)
Disassemble and clean the valve mechanism. Replace the valve if necessary.
- Increased cyclic fuel supply (rack lock disengaged)
Replace injection pump rail
Muffled crankshaft noise. The frequency increases with increasing engine speed
- An unacceptable increase in the gap between the journals and the main bearing shells as a result of the use of oil that does not match
specified in this manual, or reduce pressure and oil supply.
Grind the necks to the repair size and replace the liners, change the oil and check the operation of the oil pump.
- Inadmissible increase in the gap between the thrust half rings and the crankshaft.
Replace thrust half rings with new thicker ones.
- Loosening the bolts of the flywheel to the crankshaft.
Find the cause and tighten the bolts.
Conrod bearing clatter is harsher than main bearing clatter. It is heard when the engine is idling and increases with increasing crankshaft speed
- An unacceptable increase in the gap between the journals and the connecting rod bearing shells as a result of using an oil that does not correspond to the specified one, or a decrease in pressure and oil supply.
Grind the necks to the repair size and replace the liners, change the oil and check the operation of the oil pump.
Piston knock is muffled, caused by pistons beating against cylinders. Heard at low crankshaft speed and under load
- Inadmissible increase in the gap between pistons and cylinders.
Replace pistons and, if necessary, cylinder liners.
- Strong wear of the ends of the piston rings and the corresponding grooves on the piston.
Replace piston rings and, if required, pistons.
The sound of piston pins, double, metallic, sharp is caused by a large gap. Better heard when the engine is idling
- Inadmissible increase in the gap between the pin and the bushing of the upper head of the connecting rod.
Replace the pin and, if necessary, the connecting rod.
Increased fluid temperature in the cooling system
- Weak tension or breakage of the water pump drive belts.
Tighten or replace belts.
- Faulty thermostats
Replace thermostats.
- Pollution of the radiator core.
Clean the radiator core from dirt.
Increased coolant consumption
- Radiator damage
Repair damage or replace radiator
- Liquid leakage through the mechanical seal of the water pump.
Replace the mechanical seal.
- The ingress of coolant into the lubrication system through the rubber sealing rings of the cylinder liners or through the rubber gaskets of the cylinder heads.
Replace cylinder liner O-rings or rubber gaskets.
* Before looking for the cause of a malfunction in the lubrication and cooling system, you need to make sure that the oil pressure and temperature indicators are working.
Electric torch device (ETF)
Faulty EFU spark plug, 30A fuse is on
- Closing the spiral of a thermal switch or electrical wires
If the candles are in good order, disconnect the wire from the thermal relay that connects it to the power button of the EFU. The absence of a circuit when the EFU is turned on again indicates that the thermal relay coil is closed.
In this case, replace the thermostat. If the spiral of the thermal relay is intact (determined by touch) and when the wires are disconnected from the candles, a short circuit occurs, then this indicates a short circuit in the electrical wires. Remove the short.
- Closing the candle to ground
Disconnect the wire from the output of the left candle, eliminating the contact of the tip with the ground, and turn on the EFU again. If shorted, disconnect the wire from the right spark plug terminal.
Absence of closure indicates a closure of the right candle. Replace failed spark plug.
After the short circuit is eliminated, it is recommended to check the condition of the insulation of the electrical wires, the operability of the thermal relay and the EFU switch-on relay, and if the short circuit occurred when the engine was started, the operability of the shunt relay
EFU does not work, voltage is not supplied to the EFU
- Burn out e thermal relay spirals
Turn on the EFU and check the voltage at the thermal relay outputs. The absence of voltage at the output from the side of the plug connection, while there is voltage at the other output, indicates a burnout of the spiral. Replace thermostat.
- Burnout of candles or lack of contact in the circuit
Turn on the EFU and check if there is voltage at the terminals of each EFU product, starting with the torch candles. The presence of voltage at the output of the right candle indicates the burnout of the candles. Replace spark plugs or restore contact.
- Burnout of one of the candles
Turn on the EFU for 10-15 seconds, then replace the cold plug.
No candle torch
- Lack of fuel supply to the candle
Loosen the fuel inlet fitting on the spark plug. Turn on the EFU and, after the indicator lights up (opening the solenoid valve), crank using the starter crankshaft.
If fuel does not seep through the loose fitting threaded connection when the valve is open, repair the fuel supply system.
- Fuel not passing through the spark plug
Unscrew the spark plug from the manifold. Rinse and blow out the jet, fuel filter and fuel supply cavities with compressed air. Check for the presence of a torch flame, for which:
- - connect the fuel pipe and electrical wires to the spark plug;
- - ensure a reliable connection of the spark plug body to the ground and make sure that the lead is isolated from the ground;
- - turn on the EFU and turn the crankshaft using the starter.
If there is no flame, replace the defective spark plug.
Electrical equipment
The charge circuit warning light is on at rated engine speed
- Loosening the tension of the alternator drive belts
Adjust belt tension
- Contamination of slip rings
Wipe the rings with a cotton cloth moistened with clean gasoline. If contamination persists, clean with glass sandpaper and wipe again with a napkin
- Wear or sticking of brushes in brush holders
Check the height of the brushes, their free movement in the channels of the brush holder and the force of the springs; if necessary, replace the brush holder or brushes
- Breakdown of the rectifier unit
Replace block
- Short circuit of the stator winding
Replace stator assembly
- Violation in the excitation circuit
Check the excitation circuit is working
- Wear of bearing parts or their destruction
Replace Generator
- Generator fan deformation
Fix bent spots
Bearing overheating
- Excessive belt tension
Adjust belt tension
Generator brush wear too fast
- Contamination of slip rings
Wipe the rings with a cotton cloth moistened with clean gasoline. If necessary, clean with glass sandpaper and wipe again with a napkin
- Radial runout of slip rings
Check the radial runout of the rings. If required, grind slip rings
Charging current too high
- Short circuit in the brush assembly of the generator or in the circuit between the generator and the regulator
Remove shorting
- Faulty voltage regulator
Replace Regulator
- Malfunction of the relay for turning off the excitation winding of the generator
Replace relay
Increased noise level during generator operation
- Pulley loosening
Tighten the nut
- Lack of contact between brushes and commutator
Wipe the collector with a clean cloth soaked in gasoline, or clean it. Clean the brushes or replace them with new ones. Check the condition of the brush springs and replace them if they are defective. Check if the brushes in the brush holders are jammed
Starter
Starter not working
- Short circuit or open circuit of the retracting winding of the traction relay
Replace relay
- Breakage or lack of contact in the power supply circuit
Find the damage and restore contact
- Hanging brushes
Remove the brush holder, remove the brushes and remove brush dust
- Starter relay failure (738.3747-20)
Replace relay
- Open circuit inside the starter
Check and repair starter or replace starter
The crankshaft of the engine does not turn with the starter (the traction relay is activated)
- Discharging batteries
Charge batteries
- Violation of the AB charging circuit
Troubleshoot
- Faulty voltage regulator
Replace Regulator
- Oiling or contamination of the brush-collector assembly
Clean the collector and brushes from oil, dirt, copper-graphite dust
- Poor contact of the starter housing with the mass of the power plant
Ensure connection reliability
- Using an oil that doesnt match the season
Change the oil
After starting the engine, the armature continues to rotate
- Malfunction of the traction relay
Replace relay
- Welding starter relay contacts (738.3747-20)
Replace relay
When the starter is turned on, the traction relay does not work (no characteristic click)
- Discharging the battery
Charge battery
- Breakage of the retracting winding of the traction relay
Replace relay
- Faulty instrument switch and starter
Replace switch
- Open or short circuit of the starter relay winding (738.3747-20)
Replace relay
Starter armature rotates but does not turn crankshaft
- Breakage of the teeth of the flywheel crown or gear wheel
Replace flywheel ring or drive gear
- Violation of starter adjustment
Adjust the starter
- Drive failure
Replace Drive
When the starter is turned on, repeated clicks of the traction relay and impacts of the drive gear against the flywheel rim are heard
- Unreliable contact of the starter traction relay circuit
Check contact connections and remedy the problem
- Malfunction of the holding winding of the traction relay
Replace the traction relay
- Malfunction of the winding or contact connection of the starter relay (738.3747-20).
Replace relay
When the starter is turned on, noise (grinding) of the drive gear is heard
- Installation of a starter with a warp
Install the starter correctly
- Incorrect adjustment of the moment of closing the contacts of the traction relay
Adjust the gap between the gear and the thrust washer when the starter is engaged
The drive gear does not systematically engage with the flywheel ring during normal relay operation
- The presence of burrs on the ends of the teeth of the flywheel or drive gear
Filing and deburring the teeth of a flywheel ring or drive gear
- Wear of the ends of the teeth of the flywheel crown or drive gear
Replace flywheel ring or drive gear