ADJUSTMENT WORKS AND MAINTENANCE OF THE COMPONENT PARTS OF THE DT-75M TRACTOR.
Tractor DT-75M. Adjustment of gaps in gas distribution and decompression mechanisms
Tools, fixtures: socket wrench S = 27, wrenches S = 10,12,14,17, torque wrench, screwdriver, pliers, crankshaft crank, set of probes.
Check and adjust clearances on a cold engine or 15 minutes after stopping it:
A) disconnect the decompressor linkage and remove the cylinder head caps;
B) check the tightness of the rocker arm strut fastening nuts, the tightening torque of the cylinder head fastening nuts and, if necessary, tighten them;
C) turn on the decompression mechanism using the key (by the flats of the roller);
D) observing the rocker arms of the valves (Fig. 69) of the fourth cylinder, turn the crankshaft with the handle until the valves in this cylinder overlap (the exhaust valve has not yet closed, and the inlet valve has just begun to open);
E) unscrew the mounting pin (Fig. 70) from the flywheel housing and insert its uncut part into the same hole until it stops in the flywheel;
E) while pressing the mounting pin, slowly turn the crankshaft until the pin enters the hole on the flywheel. In this position of the flywheel, the piston of the first cylinder will be at TDC of the compression stroke;
G) turn off the decompression mechanism;
H) check the gap between the valve stem and the rocker arm of both valves of the first cylinder with a feeler gauge and adjust if necessary. With a properly adjusted gap, a 0.25 mm thick probe should enter with light pressure, a 0.3 mm thick one with force.
To adjust the gap:
Rice. 69. Tractor DT-75M. Engine location
unscrew the locknut of the adjusting screw;
Insert a feeler gauge 0.25 mm thick into the gap;
Screw in or out with a screwdriver the adjusting screw
Until the required clearance is obtained, holding the locknut with a wrench;
Lock the adjusting screw with a locknut, holding it with a screwdriver;
Check the gap with a feeler gauge by turning the push rod by hand to make sure that it is not jamming;
i) adjust the decompression mechanism for this cylinder:
Install the decompressor roller so that the axis of the adjusting screws 9 (Fig. 25) is vertical;
Loosen the locknut of the adjusting screw and turn it in or out until there is a full gap between the valve and the rocker arm (0.25-0.30 mm),
and then screw it in one turn and lock;
J) screw the adjusting pin into the hole of the flywheel housing;
K) sequentially adjust the clearances in each cylinder, as indicated above, in the order of their operation (1-3-4-2).
Rotate the crankshaft 180° in the direction of rotation to adjust the valve clearances and decompression mechanism of the next cylinder.
After adjusting the clearances, start the engine and listen to its operation. If valve knocking occurs, stop the engine and check the clearances again. When re-checking, the gaps should be within 0.2-0.35 mm;
L) install the cylinder head caps, making sure that the gaskets are installed correctly.
Tractor DT-75M. Lubrication valve adjustment
Tools, fixtures: stand for checking lubrication system units, wrenches S = 12,14,17,22,27,32,36, socket wrench S = 12, hammer, chisel, pliers, screwdriver.
With a decrease in oil pressure in the main oil line, it is allowed to re-adjust during maintenance No. 3
Valves of the lubrication system. Adjust the valves on the stand for the opening pressure: drain valve - 4.5-5.0 kgf / cm2; pressure reducing valve of the discharge section of the oil pump - 9.0-9.5 kgf / cm2; safety valve of the radiator section of the oil pump - 2.5-3.2 kgf / cm2.
Adjust the drain valve installed in the centrifuge body with an adjusting screw, the pressure reducing and safety valves of the oil pump - with shims. After adjusting the valves, check the performance of the oil pump on the stand.
9.2. Special types of maintenance
9.2.1. Maintenance in preparation for operational run-in
Remove preservative grease;
Perform maintenance operations 2, 3, 4, 6, 7, 8, 9,10 from table 9.1. When performing operation 10, be sure to tighten the bolts of the A-01 type diesel fuel pump drive coupling;
Start the diesel engine, listen to it, check the readings of instrumentation for compliance with established standards.
9.2.2. Maintenance during operational break-in
During the operational break-in, perform the daily maintenance operations from Table 9.1.
9.2.3. Maintenance at the end of operational break-in
Perform maintenance operations 3, 4, 5, 6, 8,10, 11, 12, 15 from table 9.1;
9.2.4. Seasonal maintenance during the transition to the autumn-winter period of operation (STO-OZ)
This maintenance must be carried out before the average daily ambient temperature drops to + 5 ° C:
If the diesel cooling system was filled with water, then drain the water and fill the cooling system with a low-freezing liquid, see paragraph 6.4.
If the diesel cooling system is constantly filled with a low-freezing liquid, then it is necessary to check the freezing point of this liquid. Anti-freeze fluid should be changed every 3 years.
If summer grade motor oil was used, change it to winter grade motor oil or multigrade motor oil, see paragraph 6.2.1.2.
9.2.5. Seasonal maintenance during the transition to the spring-summer period of operation (STO-VL).
This maintenance is performed after an increase in the average daily ambient temperature to + 5 ° C:
Carry out the next scheduled maintenance;
If winter grade motor oil was used, change it to summer grade motor oil or multigrade motor oil, see paragraph 6.2.1.2.
9.2.6. Maintenance under special operating conditions
When operating a diesel engine under special conditions, the accepted frequency and scope of diesel maintenance work is maintained (see Table 9.1), and the following work is additionally introduced or performed more frequently.
1) In desert conditions, on sandy soils and with increased dust content in the air (with an average dust content in the air of 1 g / m 3 or more):
Refuel diesel with oil and fuel only in a closed way;
Carry out the air cleaner maintenance operation every shift (or according to the clogging indicator).
2) When operating diesel engines in the conditions of Central Asia or South Kazakhstan:
Carry out the air cleaner maintenance operation every shift (or according to the clogging indicator);
Replace the fuel filter cartridges after 500 hours (or according to the clogging indicator);
Replace the oil filter elements after 250 hours.
3) On swampy soils:
Every shift clean the outer surfaces of the radiators of the cooling and lubrication systems, the crankcase of the diesel engine.
4) On rocky ground:
Every shift check the bottom cover of the diesel crankcase and the fastening of the oil drain plug from the bottom cover of the crankcase for damage.
5) With a high frequency of engagements of the clutch (more than 50 engagements per hour):
Carry out clutch adjustment, as well as lubrication of the front and outer bearings of the clutch shaft at each TO-1.
9.2.7. Maintenance during preparation for storage and removal from storage
Carry out maintenance during the preparation of the diesel engine for storage and removal from storage in accordance with the instructions in Section 11 "Storage and Preservation".
9.3. Maintenance Instructions
9.3.1. Valve clearance adjustment.
The thermal gap between the valve stem and the rocker arm ensures the tightness of the valve seat on the seat and compensates for the thermal expansion of parts during engine operation. The thermal gap at the intake and exhaust valves must be checked and adjusted on a cold diesel engine or at least 15 minutes after the diesel engine has stopped. The value of the thermal gap should be 0.25 - 0.30 mm for intake and exhaust valves.
The sequence of checking and adjusting clearances:
Clean the caps of the cylinder heads from dust and dirt;
Turn away bolts of fastening of caps and remove caps;
Observing the rocker arms of the valves of the sixth cylinder for diesel type A-01 or the fourth cylinder for diesel type A-41, turn the crankshaft clockwise (view from the side of the fan) until the valves in this cylinder overlap (the exhaust valve is not yet closed, and intake just started to open).
Attention! The intake valve of each cylinder is located closer to the fan, and the exhaust valve is closer to the flywheel. The first cylinder is located on the fan side, the last cylinder is on the flywheel side;
Unscrew the mounting pin (Fig. 9.2) from the flywheel housing and insert its unthreaded part into the same hole until it stops in the flywheel;
While pressing the dowel pin, slowly rotate the crankshaft in the same direction until the dowel pin enters the hole in the flywheel. In the first cylinder, in this position of the flywheel, the piston is at TDC on the compression stroke, and both valves are closed.
Check with a feeler gauge 0.3 mm (U5-4904, available in the diesel spare parts kit) the gap between the valve stem and the rocker arm (Fig. 9.3) for both valves of the first cylinder. The probe must enter the gap with force;
If necessary, adjust the clearance as follows:
Loosen the rocker arm adjusting screw locknut. Insert a 0.3 mm probe into the gap and, turning the adjusting screw with a screwdriver, set the required gap. Tighten the locknut with a wrench while holding the screw with a screwdriver. Check the gap with a feeler gauge by turning the rod by hand to make sure it is not jamming; - screw the dowel pin into the hole in the flywheel housing
Consistently check and adjust the clearances in each cylinder in the order of operation of the cylinders 1-5-3-6-2-4 for an A-01 diesel engine and 1-3-4-2 for an A-41 diesel engine. To adjust the clearances in the valves of the next cylinder, turn the crankshaft clockwise by 120 degrees for an A-01 diesel engine and 180 degrees for an A-41 diesel engine;
Thoroughly clean the sealing surfaces of the cylinder heads and caps and the cylinder bore for the injector. Check the condition of the rubber seals, replace them if necessary;
Install the caps on the cylinder heads and tighten the cap bolts.
9.3.2. Replacing the fuel filter cartridges
Replacement of filter cartridges FT 041.1105010 (coarse cleaning) and
FT 044.1117010 (fine cleaning) is performed when a signal is received from the fuel pressure sensor, or every 2000 hours at the next TO-3. The coarse fuel filter cartridge is located on the left side of the block fuel filter and is shorter than the fine filter cartridge.
Replacement sequence:
Shut off the fuel supply valve to the diesel engine from the fuel tank;
Drain the fuel from the filter cartridges into a suitable container. To do this, put a hose with an inner diameter of 8 mm on the fitting of the fuel drain plug from the filter cartridge and unscrew the fuel drain plug by 1.5-2 turns until a fuel jet appears from the hose.
Attention! Do not pour fuel on the ground!
Unscrew the filter cartridges;
Thoroughly clean the sealing surfaces of the fuel filters from dirt;
Lubricate the rubber o-rings of the new filter cartridges with clean engine oil;
Screw on the filter cartridges until they come into contact with the sealing surface of the filter and then turn another ¾ turn;
Open the fuel cock;
Fill the fuel system with a manual priming pump. If necessary, bleed the air from the fuel system. To do this, unscrew the air bleed plug on the fuel filter housing and pump fuel until air bubbles in the escaping fuel disappear. Close the air removal plug;
Start the diesel and check for fuel leaks.
9.3.3. Changing the oil in the crankcase of a diesel engine
Change the oil in the diesel crankcase in the following sequence:
Prepare a suitable container for used oil;
Start the diesel, warm it up to operating temperature and stop;
Unscrew the drain plug in the lower crankcase cover and drain the used oil into a prepared container;
Replace the oil filter elements (clause 9.3.4);
Screw the drain plug securely into the lower crankcase cover;
Fill in fresh engine oil through the oil filler pipe to the top mark of the oil meter;
Start the diesel, check the oil pressure gauge and make sure there are no oil leaks;
Before starting the next working day, check the oil level, if necessary, add oil to the upper mark of the oil dipstick.
9.3.4. Replacing the oil filter elements
It is recommended to replace the filter elements of the oil filter no earlier than 30 minutes after stopping the diesel engine. 
During this time, the filter parts will cool down and the oil will drain from the filter.
Replacement sequence for each of the two filters
elements:
Unscrew cap 3 (Fig. 9.4) with filter element 4
for hexagon 1 on the cap;
Overcoming the force of the spring
2 , move the clamp 5 until the side collars go beyond the cap projections;
Rotate the clamp by 60 degrees until the clamp tabs align with the grooves of the cap and remove the clamp with the filter element from the cap;
Rinse the cap in diesel fuel;
Install a new gasket 7 (KMF-30.202) on the cap;
Clean the sealing surface of the filter housing 8 from dirt;
Install a new filter element (840-1012040-12) on the clamp, insert into the cap and fix. When assembling ensure that spring 2 gets into the recess of the filter element cover.
Lubricate the cap gasket with oil;
Screw the cap onto the fitting 6 of the filter until it touches
with the mounting pad of the filter housing (8) , then tighten
with a key for the hexagon of the cap by 0.5-0.6 turns (tightening torque
Attention! Environmental regulations must be observed when disposing of filter elements!
9.3.5. Bearing lubrication
To lubricate the bearings, use grease as recommended in Section 6.3.
The grease fittings for lubricating the water pump bearings and the clutch outer bearing are outside and accessible.
The clutch shaft front bearing oiler is located on the outer diameter of the flywheel. Access to it is through a side hole in the flywheel housing, closed with a metal cover, which is mounted on one bolt.
Access to the oiler of the clutch release bearing is through a hatch in the clutch cover, closed by a cover, which is mounted on 4 bolts. To open the hatch, it is necessary to loosen the bolts securing the cover and turn the cover to the side.
Inject water pump bearings until grease appears from the control hole. To lubricate the outer, release and front bearings of the clutch, make 3-4 injections with a syringe.
9.3.6. Checking and tightening the external fastenings of diesel units and parts.
Loose fasteners, leaks of coolant, oil or fuel are not allowed. Therefore, check and tighten the fasteners in a timely manner:
Clutch covers, pipe clamps for the air intake system and cooling system, intake manifold, diesel supports, oil filter, muffler, hydraulic pump drive housings, water pump, gear housing cover, water pipe, exhaust manifold, fuel lines, fuel pump drive, side gas distribution hatches , fan and alternator bracket.
9.3.7. Air compressor service.
Servicing the pneumatic compressor is carried out together with the maintenance of the A-41SI-02 diesel engine on which it is installed. The list of maintenance works for the pneumatic compressor is given in Table 9.2:
Table 9.2.
| Content of works | Technical requirements | Note |
| Check the fastening of the compressor on the diesel engine, the tightening of the nuts of the studs securing the head, cover and other fasteners. | Tighten the stud nuts evenly. Final tightening torque 15…18 Nm. | At each TO-3 (after 1000 hours). |
| Remove the compressor head and, if soot is found, clean the head, piston, plate, valves, wash them in kerosene and dry with compressed air. | |
|
| Check the tightness of the valves, if necessary lap the valves or replace them. | The valves should fit snugly against the plate without applying force to them. The gap between the plate and the valve working surface, when simulating clamping conditions, should not exceed 0.01 mm. | Through one TO-3 (after 2000 hours). |
9.3.8. Clutch adjustment
To adjust the clutch and lubricate the release bearing, there is a hatch on the clutch cover. To open the hatch, it is necessary to loosen the bolts securing its cover and turn the hatch cover to the side.
Full stroke of the clutch should be 24 -1 mm for the diesel clutch type A-41 and 22 +2 mm - for the diesel clutch type A-01. Check the full travel of the disengagement clutch with the clutch fully depressed using template 41-4922 (available in the diesel spare parts kit). The template should enter freely, but without a large gap, between the release clutch housing (thrust bearing housing) and the clutch shaft outer bearing housing.
For A-41 type diesel clutch, use the side of the template marked "24 A-41", for type A-01 diesel clutch, use the side of the template marked "22 A-01M".
If necessary, adjust the full travel of the clutch by changing the length of the clutch control drive rods.
Release clutch free play(the gap between the stop of the clutch and the ring of the pressure levers) must be 4±0.5 mm (thickness of the template 41-4922).
Check the gap between the stop of the clutch and the ring of pressure levers with a template at three equally spaced points around the circumference of the ring. The release clutch housing (thrust bearing) must occupy the rearmost position (rest against the outer bearing housing).
Gap adjustment is carried out by adjusting nuts. Before adjusting the clutch of the A-01 diesel engine, it is necessary to unscrew the lock nuts, and after adjusting them, tighten them again. Before adjusting the clutch of the A-41 diesel engine, it is necessary to unscrew the bolts securing the lock washers and remove the lock washers, after adjusting, install the lock washers in place and tighten the bolts of their fastening.
To reduce the gap, the adjusting nuts must be tightened, and to increase the gap, unscrew.
9.3.9. Maintaining an Air Cleaner with Paper Filter Elements
Service the air cleaner in the following sequence:
Remove the monocyclone, clean the mesh, swirler and dust slots of the monocyclone;
Unscrewing the clamps (wing nuts), remove the air cleaner cover and remove the paper filter elements (main and safety) from the housing;
Blow the filter elements with compressed air first from the inside and then from the outside until the dust is completely removed.
Attention! In order not to damage the filter elements, the compressed air pressure during blowing should be no more than 3 kgf / cm 2. When blowing, the air jet should be directed at an angle to the surface of the filter element.
It is forbidden to purge the filter elements with exhaust gases!
In the absence of compressed air, as well as in the case of oiling of the filter elements or their contamination with soot from exhaust gases, it is allowed to wash the filter elements in a cleaning solution, followed by rinsing in clean water. Washing solution can be prepared on the basis of soap paste OP-7
(or OP-10), or universal washing powder or laundry soap.
Attention! It is forbidden to wash the filter elements in diesel fuel or gasoline! Do not dry the filter elements at temperatures above 80 O C and do not use compressed air to speed up drying!
After cleaning the filter elements, check their integrity by inspection in a darkened room with illumination from inside the element. In this case, any bright spot of light from the outside will show that the filter element is damaged and must be replaced;
Reassemble the air cleaner in reverse order. Before installing the filter elements in the air cleaner housing, check the condition of the O-rings. Make sure that the filter elements are correctly installed in the housing and securely tighten the wing nuts. Wing nuts must be tightened by hand, without the use of wrenches or other tools.
The filter elements of the air cleaner must be replaced if the integrity of the filtering curtain is found to be broken, if the body parts are damaged, if a fourth flush is necessary, and also if the dust capacity is greatly reduced.
For replacement, use the main filter element 250I.1109080-02 and the safety filter element 250I.1109080-10.
Attention! To ensure reliable operation of the air cleaner and diesel engine, it is not allowed:
- direct ingress of water into the air cleaner when washing a tractor or diesel engine;
- operation of a diesel engine without an air intake;
- operation of a diesel engine in a gassed environment;
- carrying out welding work on the parts of the air cleaner without removing the filter elements;
- depressurization of the air purification system.
9.3.10. Maintenance of an air cleaner with an oil bath (for diesel A-41SI-1)
Service the air cleaner with an oil bath in the following sequence:
Remove the monocyclone, clean the mesh, swirler and dust collecting slots of the monocyclone;
Remove the sump, take out the large cassette, drain the oil, take out the plastic oil pan from the sump, wash the sump and oil bath in diesel fuel, clean the holes in the oil bath;
Install an oil bath in the sump and fill it with used, settled and filtered engine oil along the center line of the lower annular belt. The brand of oil must correspond to the season of operation. At temperatures below -20 ° C, use a mixture of 2/3 oil and 1/3 diesel fuel to fill the air cleaner;
Remove the two polyurethane foam filter elements from the air cleaner housing;
Wash the large cassette and filter elements in diesel fuel. Shake off the cassette, wring out the filter elements. To completely remove diesel fuel, blow the cassette and filter elements with compressed air or soak them in air for 10-15 minutes;
Install the filter elements in the air cleaner housing. The filter element with fine pores should be installed first;
Install a large cassette in the air cleaner pan;
Check the condition of the sealing rings;
Install the pallet so that the lock located on the left side of the maintenance label is located opposite the reference on the body.
Attention! It is not allowed to operate a diesel engine without a monocyclone, without oil in the air cleaner pan!
It is not allowed to suck air between the body and the air cleaner pan!
It is not allowed: to fill in oil above the annular belt; carry out welding work on or near the assembled air cleaner; to heat the air with an open flame in front of the monocyclone grid to facilitate diesel start-up!
9.3.11. Checking and adjusting the injectors
Attention! Checking the injectors for the pressure of the start of injection and the quality of the fuel atomization should be carried out in a specialized workshop. It is not allowed to carry out such inspection and disassembly of injectors in the field!
Instructions for removing and installing injectors:
Disconnect the drain fuel line from the injectors;
Remove caps of heads of cylinders;
Disconnect the high pressure fuel lines from the injectors;
Turn away nuts of fastening brackets of atomizers and take out atomizers from glasses in heads of cylinders;
Wipe the nozzles with a non-fibrous cloth;
Remove the copper gasket from the injectors;
Close the nozzle openings with protective plugs, and the nozzle of the sprayer with a protective cap (plugs and a cap are available in the diesel spare parts kit);
Screw protective plugs onto the fittings of the high-pressure fuel lines (available in the diesel spare parts kit);
Take the injectors to a workshop for inspection and adjustment;
After checking and adjusting, install the injectors on the diesel (installation in reverse order).
Before installing the injectors in the cylinder heads:
1. Put new copper gaskets 01-2022 on the atomizers until they fit on the plane of the atomizer nut and lightly grease them with grease (Litol-24M) so as not to lose the gaskets during installation.
2. Clean the nozzle cups in the cylinder heads from oil and dirt, make sure that no old gaskets are left in the cups.
After installing the nozzles and before installing the caps:
Pour engine oil into the sockets around the nozzles from an oiler or supercharger;
Crank the diesel with a starter without supplying fuel and make sure that there is no breakthrough of gases around the nozzles.
Data for adjusting and mounting nozzles:
Table 9.3
| Parameter | Parameter value | Note |
| 1 | 2 | 3 |
| Injection start pressure, MPa (kgf / cm 2) | 25 +1,2 (250 +12) | During operation, a pressure drop is allowed to a value of at least 22.5 MPa (225 kgf / cm 2) |
| Fuel atomization quality | Fuel injection by a new injector is accompanied by a characteristic sound (crackling), fuel is injected into the atmosphere in a foggy state from four nozzle holes and is evenly distributed over the cross section of the jet cone. | Diesel-powered injectors are allowed to have no characteristic sound and jet spraying |
| Injection frequency when checking the quality of spraying, times / min | 70…80 | |
| Tightening torque of the nozzle bracket nut, Nm | 50…70 | |
| Nozzle designation | 204И.1112010 | |
| Gun designation | 204И.1112110 | |
| Designation of the copper sealing gasket for the injector | 01-2022 | The new copper gasket with concentric ridges is 0.7 mm thick (compressed gasket thickness is 0.5 mm). Attention! Installation of other gaskets under the nozzle is not allowed! |
| Injection start pressure control method | The injection start pressure is adjusted by changing the thickness of the shims under the nozzle spring. Changing the thickness of a set of two gaskets by 0.1 mm leads to a change in the injection start pressure by about 17 kgf/cm 2 . | A spare set of gaskets for adjustment is included in the diesel spare parts kit. The number of shims under the injector spring should be no more than two. |
| Designation of a set of shims | 204I.1112010 ZI | Attention! Other shims must not be used! |
9.3.12. Checking and adjusting the high pressure fuel pump (TNVD)
Attention! Checking and adjustment of the injection pump must be carried out in a specialized workshop!
The sequence of removal and installation of high pressure fuel pump
1. Removal and installation of high pressure fuel pump for diesel type A-41
Unscrew three nuts 2 (Fig. 9.5) fastening the cover 4 of the injection pump drive to the gear housing cover 1, remove the washers and the cover from the studs;
Turn out three bolts 3 of fastening of coupling 5 of HPFP to a gear wheel 6 of a drive of HPFP;
Unscrew the high and low pressure fuel lines from the injection pump, close the injection pump openings and high pressure fuel line fittings with plastic plugs (available in the diesel spare parts kit), see fig. 9.6;
Disconnect control rods from injection pump;
Disconnect the centralized lubrication oil line from the injection pump;
Remove the 4 bolts securing the injection pump to the gear housing. The two upper bolts are unscrewed from the side of the gear housing cover, and the two lower bolts are unscrewed from the injection pump side;
Move the injection pump to the left until the drive coupling comes out of the hole in the gear housing and remove the injection pump;
The installation of the injection pump is carried out in the reverse order. Before screwing in bolts 3 of the injection pump drive, align hole A (Fig. 9.5) in the drive gear with the hole in the injection pump drive coupling;
Check and adjust the fuel injection timing. Finally tighten bolts 3 to 50 Nm after adjusting the fuel injection advance angle;
Install the injection pump drive cover on the gear housing cover.
2. Removal and installation of high pressure fuel pump for diesel type A-01
Close the fuel cock between the fuel tank and the diesel;
Turn the diesel crankshaft to the position corresponding to the beginning of fuel injection by the first section of the injection pump (marks 1 and 2 should be visible, Fig. 9.7, on the drive fork of the injection pump);
-
unscrew the high and low pressure fuel lines from the injection pump, close the injection pump openings and high pressure fuel line fittings with plastic plugs (available in the diesel spare parts kit), see fig. 9.6;
Disconnect the control rod(s) from the injection pump;
Disconnect the centralized lubrication oil line from the injection pump (if any);
Remove the protective casing of the injection pump drive;
Disconnect from high pressure fuel pump the oil lines for supplying and draining centralized lubrication (if any);
Unscrew two bolts 11 (Fig. 9.7) on the fuel pump drive coupling;
Turn away four bolts of fastening of TNVD to an arm;
Remove injection pump;
The installation of the injection pump is carried out in the reverse order. Connect the drive yoke to the injection pump drive coupling in the same position. After installing the injection pump, pump fuel by removing air from the fuel system and adjust the fuel injection advance angle.
The adjustment parameters of the injection pump are shown in Table 9.4.
Table 9.4
| Diesel brand | A-41SI-1 | A-41SI-02 A-41SI-03 | A-01MSI-1, A-01MSI-1.30 A-01MRSI-1, A-01MKSI-1 |
| High pressure fuel pump brand | 7741.1111005 (YAZDA) | 7741.1111005 (YAZDA) or PP4M10P1i 4379 (motorpal) | 6271111005-30 (NZTA) or 6ТН-10х10 (AZTN) |
| Adjusting parameters of injection pump |
|||
| Rotational speed corresponding to fuel supply shutdown, min -1 | 1030 No more | 1030 No more (for PP4M10P1i 965…995) | 960 No more |
| Rotational speed corresponding to the beginning of the regulator action, min -1 | 905 +10 | 905 +10 | 870 +10 |
| Cyclic fuel supply, mm 3 / cycle, at a speed, min -1 Figures in parentheses indicate the unevenness of the cyclic fuel supply in the sections of the high-pressure fuel pump,%, not more than | 25…30 at 300 ±10 (35) 114…120 at 500±10 (8) 120…126 at 600±10 (8) 106…110 at 880±10 (6) | 25…30 at 124…130 at 500±10 (8) 130…136 at 600±10 (8) 110…114 at 880±10 (6) | 25…30 at 300±10 (35) 125…131 at 600±10 (8) 102…105 at 850±10 (6) |
| Test conditions under which the adjustment parameters of the injection pump are indicated |
|||
| Process fluid | Diesel fuel according to GOST 305-82 |
||
| Process fluid temperature, o C | 28±5 |
||
| Bench nozzle parameters: Effective flow area of nozzle holes, mm 2 ; The pressure of the beginning of the lifting of the needle of the atomizer, kgf / cm 2 | 0,235…0,245 175…180 |
||
| Parameters of bench high pressure fuel lines: Length, mm Outer diameter, mm; Internal diameter, mm | |||
9.3.13. Checking and adjusting the fuel injection advance setting angle
9.3.13.1. Checking and adjusting the fuel injection advance angle for a diesel engine type A-41
The setting fuel injection advance angle for an A-41 diesel engine must be:
With injection pump model 4UTNI manufactured by NZTA OJSC - 28 -3
With injection pump model 7741 manufactured by JSC "YAZDA" - 23 -2 degrees of rotation of the crankshaft to TDC;
With injection pump model PP4M10P1i manufactured by f. motorpal- 20 -2
Move the injection pump control lever (or levers) to the maximum fuel supply position;
-
turn the crankshaft in the direction of rotation until fuel appears from the fitting of the 1st section of the injection pump and
install on the fitting of this section
Momentoscope, fig. 9.8;
Set the wire pointer to
gear housing cover so that the pointer point is directed to the outer cylindrical surface of the crankshaft pulley (for diesel A-41SI-03 - to the larger diameter of the pulley). The distance between the pointer and the pulley must be
Make a mark on the outer cylindrical surface of the shoulder of the crankshaft pulley against the tip of the wire pointer;
In this position of the crankshaft, put another mark on the pulley;
Measure the length between the two marks on the outer cylindrical surface of the pulley shoulder with a flexible ruler or a piece of graph paper. To find out the value of the fuel injection advance setting angle in degrees of rotation of the crankshaft, it is necessary to divide the measured length of the arc between the marks by 1.5 for the A-41SI-1 and A-41SI-02 diesel engines or by 1.8 for the A-41SI-03 diesel engine ;
Remove the injection pump drive cover (4), fig. 9.5;
Loosen the three injection pump drive bolts (3);
Put a socket wrench on the injection pump shaft nut and turn the injection pump drive clutch with the wrench together with the bolts (3), which will move along the gear grooves. Turning the clutch relative to the gear clockwise increases the fuel injection advance angle, counterclockwise decreases it.
The length of the arc on the crankshaft pulley between the TDC mark and the mark corresponding to the start of fuel supply according to the momentoscope must be:
- for diesel engines A-41SI-1 and A-41SI-02:
With injection pump model 4UTNI manufactured by NZTA OJSC - 37.5 ... 42 mm;
With injection pump model 7741 manufactured by JSC "YAZDA" - 31.5 ... 34.5 mm;
With injection pump model PP4M10P1i manufactured by f. Motorpal - 27…30 mm.
- for diesel A-41SI-03- 38 ... 41.5 mm.
After correctly setting the fuel injection advance angle, finally tighten the bolts (3) to 50 Nm and reinstall the cover (4).
Attention! To check and adjust the fuel injection advance angle, you can also use the angular marks printed on the outer cylindrical surface of the flywheel. On the surface of the flywheel, the TDC mark of the piston of the 1st cylinder and the angular marks from 21 to 31 degrees to TDC with an interval of 2 degrees c.v. are applied. To observe these marks, use the inspection hole in the flywheel housing and, if necessary, a mirror . The inspection hole is closed with a cover, which is fixed with one bolt. At the TDC position of the piston of the 1st cylinder, the TDC mark on the flywheel is at the level of the bottom wall of the hole.
9.3.13.2. Checking and adjusting the fuel injection advance angle for diesel type A-01
The setting fuel injection advance angle for an A-01 diesel engine must be 28 -3 degrees of rotation of the crankshaft to TDC.
Check the fuel injection advance angle in the following sequence:
Open the fuel supply valve from the tractor fuel tank to the diesel engine;
Move the injection pump control lever to the maximum fuel supply position;
If necessary, bleed the fuel system with a manual priming pump;
Unscrew the high pressure fuel line from the fitting of the 1st section of the injection pump;
Turn the crankshaft in the direction of rotation until fuel appears from the fitting of the 1st section of the injection pump and install a momentoscope on the fitting of this section, fig. 9.8;
Turning the crankshaft forward (clockwise), using the adjusting pin, find the TDC position of the piston of the 1st cylinder (see paragraph 9.3.1 and Fig. 9.2);
Remove the fuel pump drive cover;
Install the wire pointer on the fuel pump housing so that the pointer point is opposite mark 1 on the fuel pump plug (see Fig. 9.7).
Turning the crankshaft back and forth, achieve a jet of fuel without air bubbles from the momentoscope tube;
Shake or squeeze a small amount of fuel out of the momentoscope tube with a rubber band until a visible meniscus of fuel appears in the tube;
Turn the crankshaft back (counterclockwise), then slowly turn it forward. At the moment the fuel level begins to rise in the momentoscope tube, stop rotating the crankshaft;
The fuel injection advance angle is set correctly if, in this position, the tip of the wire pointer coincides with mark 2 on the pump fork (see Fig. 9.7) or is located between the marks at a distance of no more than 1.6 mm from mark 2.
To change the fuel injection advance angle:
Loosen the bolts (5) securing the plate pack to the flange (7), fig. 9.7;
Rotate the plate pack along with the pump shaft and the bolts (5) that will move in the grooves of the flange (7). Turning the plate pack clockwise increases the fuel injection advance angle, counterclockwise decreases it.
After correctly setting the fuel injection advance angle, finally tighten the bolts (5) to 50 Nm and reinstall the injection pump drive cover.
9.3.14. Adjusting the tension of the drive belts of the generator, fan and pneumatic compressor.
The belt tension is normal if, when pressed with the thumb in the middle between the pulleys, it bends by 8-10 mm.
Belt tension adjustment:
1. Adjust the tension of the generator drive belt by turning the generator, for which:
Loosen the bolts securing the generator legs to the generator bracket;
Loosen the bolt securing the tensioner to the generator;
By turning the generator, adjust the belt tension;
Tighten the bolts.
2. Adjust the tension of the fan drive belt by moving the tension roller.
3. Increase the tension of the pneumatic compressor drive belt by moving the shims located between the half-pulley and the pulley plate outward under the pulley coupling bolts.
WORKBOOK
for the implementation of practical work
PM.01. "Preparation of machines, mechanisms, installations, devices for work, acquisition of assembly units"
MDK01.01. "The purpose and general arrangement of tractors, cars and agricultural machines"
Course "Appointment and general arrangement of tractors and cars"
Specialty 110809
PRACTICE #1
BLOCK-CARTERS, HEADS, CYLINDERS, GASKETS.
Goal of the work. Consider and study block crankcases, heads, cylinders, gaskets. Consolidate theoretical knowledge. Get practical skills in disassembling and assembling internal combustion engines.
Workplace equipment. Block crankcases, heads, cylinders, gaskets. Complete parts to be disassembled. Device for extrusion of sleeves. Posters, literature, tools.
Reporting procedure.
1. Draw a tool for extrusion of cartridge cases and mark the positions.
2. Describe the device of the crankcase.
______________________
________________________________________________________
_____________________________________
3. Answer questions.
KShM is intended for __________________________________________________
The gasket installed between the head block is designed for __________________________________________________
At what angle are the cylinders on the engines:
ZIL-130?______________
SMD-62?______________
D-240?________________
ZMZ-53?_______________
A-41?_________________
Heads made of aluminum alloy are tightened on a cold, hot engine (underline as necessary).
A dry sleeve differs from a wet sleeve in that
________________________________________________________
PRACTICAL LESSON №2.
"Pistons, piston pins, piston rings, circlips, connecting rods, connecting rod bearings"
The purpose of the lesson. Examine and examine pistons, piston rings, piston pins, circlips, connecting rods, connecting rod bearings.
Workplace equipment. Engines SMD-62, ZIL-130, etc., mounted on rotary stands with the heads of the block and the oil pan removed. Pistons, piston rings, pins, connecting rods. Piston ring installer. Posters, literature, tools.
Reporting procedure.
1. Draw a diagram of the piston with the designation of positions.
2. Describe the procedure for assembling the piston group.
___________________________________________________________________
3. Answer questions.
Why is the piston made elliptical or with a slit on the skirt?
___________________________________________
How are the piston pin circlips held in the piston bosses?
____________________________________
What is the purpose of the gap in the ring lock?
_____________________________
Which piston does not have oil scraper rings?
___________________________________________
How to determine the angle of the compression rings?
__________________________________________________
Which piston head, diesel or carburetor, has a combustion chamber?
___________________________________________
On which engines and for what purpose are locking screws installed in the grooves of the piston heads for compression rings?
______________________
Grade ______________ Instructor ____________________
PRACTICAL LESSON №3.
"Crankshafts, main bearings, flywheels"
The purpose of the lesson. Consolidate theoretical knowledge. Consider and study crankshafts, main bearings and flywheels. Get skills in partial disassembly of internal combustion engines.
Workplace equipment. SMD-62, ZIL-130 engines with crankcases removed, mounted on a turntable. Crankshafts, main bearings, flywheels. Tool kit, posters, literature.
Reporting procedure.
1. Describe the crankshaft device.
___________________________________________________________________________________________________________________________________
2. Describe the flywheel device and draw a diagram.
3. Answer questions.
The flywheel is intended for _____________________________
____________________________________
The crankshaft is designed for ________________________________________
Why are there voids in the connecting rod journals of the crankshaft?
____________________________________
Where are the marks for determining the piston of the first cylinder in the T.M.T. for engines:
Counterweights are designed for _____________________________
_________________________________________________________
Name the number of main and connecting rod journals at the crankshafts of engines:
SMD-62?_________________________________________________
ZIL-130?_________________________________________________
D-240?_________________________________________________
Grade ______________ Instructor ____________________
PRACTICAL WORK №4.
"Valve mechanism of engines"
Goal of the work. Consolidate knowledge of theoretical material. Consider and study the rocker arms, racks, roller, rocker roller spring, valve guide, valves and their springs, support plates, crackers, valve rotation mechanism. Get practical skills in partial disassembly and assembly of the gas distribution mechanism, as well as in the adjustment of thermal gaps.
Workplace equipment. Engines SMD-62, ZIL-130 and others installed on rotary stands. On the racks are cylinder heads with a valve mechanism, rocker arms, racks, a roller, a rocker roller spring, a valve guide, valves and their springs, support plates, crackers, a valve turning mechanism. Tool kit (wrenches, screwdriver, feeler gauge, valve spring puller, cleaning cloth). Posters and diagrams of gas distribution mechanisms, literature, instruction card.
Reporting procedure.
1. Draw the mechanism for turning the valve of a ZIL car with the designation of positions.
2. Answer questions.
a) Between what points of the parts is the thermal clearance of the valves measured with the lower and upper valves? _________________________________________________________________
b) What is the design difference between the intake and exhaust valves of the ZIL-130 engine?
c) For what purpose does the exhaust valve of the ZIL-130 engine turn during its opening?
___________________________________
Grade_______________ Instructor________________
PRACTICAL WORK №5.
"Adjusting the thermal clearance of ZIL-130 valves"
Goal of the work. Study the timing device. Acquire skills in adjusting the thermal clearance of valves on the ZIL-130 engine.
Workplace equipment. Engine ZIL-130. Tool kit, posters, literature.
Reporting procedure.
1. Describe the procedure for adjusting the thermal clearance of valves on the ZIL-130 engine.
______________________________________________________________________________________________________________________________________________________
_____________________________________________
2. Draw a diagram of the location of the marks for adjusting the valves on the ZIL-130 engine.
3. Answer questions.
The order of operation of the engine cylinders ZIL-130.________________
_________________________________________________________
Thermal clearance of the valves of the ZIL-130 engine: __________________
The timing is designed for ___________________________________________
_____________________________________________
The diameter of the plate at the exhaust valve is larger, smaller (underline) than that of the intake valve.
Describe the general procedure for adjusting engine valves.
Grade ______________ Instructor ____________________
PRACTICAL WORK №6.
"Adjusting the thermal clearance of the A-41 engine valves"
Goal of the work. To study the timing device of the A-41 engine. Get practical skills in adjusting the valves of the A-41 engine.
Workplace equipment. A-41 engine, tool kit, posters, literature.
Reporting procedure.
1. Describe the procedure for adjusting the valves of the A-41 engine.
______________________________________________________________________________________________________________
2. Describe the general procedure for adjusting engine valves.
__________________________________________________________________________________________________________________________________________________________
3. Answer questions.
The thermal clearance of the valves is required for ________________________________________________
The decompression mechanism serves to ____________________________
________________________________________________
The decompression mechanism acts on __________________________________________________________
The order of operation of the cylinders of the A-41 engine ______________________
Thermal clearance of engine valves А-41________________________
Grade ______________ Instructor __________________
PRACTICAL WORK №7.
"Adjusting the thermal clearance of valves D-240"
Goal of the work. To study the D-240 timing and gain practical skills in adjusting the thermal clearance of the valves of the D-240 engine.
Workplace equipment. D-240 engine, tool kit, posters, literature.
Reporting procedure.
1. Describe the procedure for adjusting valves on the D-240 engine.
____________________________________________________________________________________________________________________________________________
2.Draw a diagram of the valve and label the positions.
3. Answer questions.
The gap between the end of the valve stem and the rocker arm is _____________________ mm.
Adjust the gap between the end face of the valve and the striker of the rocker when it is turned off, turned on for maximum fuel supply (underline) and not earlier than 15 ... 20 minutes, 20 ... 25 minutes after the engine stops (underline).
What is checked before adjustment? ___________________________________________
Where is the installation mark for the first piston in the TDC? ________
____________________________________
You can speed up the adjustment as follows: _____________
__________________________________________________________
Grade _____________ Instructor ____________________
PRACTICE #8
Adjustment of the thermal gap of the SMD-60, 62 valves.
Purpose of the lesson: study the timing of the SMD-60 engine and learn how to adjust the thermal clearance of the valves of this engine.
Workplace equipment: SMD-60 engine, tool kit, posters, literature.
Domestic construction and agricultural machinery, special vehicles are equipped with various power units. One of their representatives is the A 41 diesel engine, manufactured by the Altai Motor Plant, located in Barnaul.
Specifications
A 41 is a series of four-cylinder naturally aspirated diesel engines. Their main purpose is operation in construction equipment and agricultural machines. A 41 is a high-quality, unpretentious, durable unit, easy to operate and has good maintainability, and this characteristic of A 41 engines allowed it to gain consumer recognition.
A41 taken from the DT-75 tractor:
Technical characteristics of the A 41 engine in the stock version:
- Engine weight A 41: 930 kg.
- Motor dimensions: length 1425 mm, width 827 mm.
- Execution of the block of cylinders: pig-iron BC.
- Fuel supply: diesel direct injection method.
- Cylinder operation algorithm: 1 - 3 - 4 - 2, counting is from the motor fan.
- Volume: 7.43 liters.
- Developed power: up to 90 horsepower.
- The number of revolutions according to the passport: 1750 rpm. in a minute.
- Cylinders: 4.
- Cylinder arrangement: mounted vertically.
- Piston stroke length: 140 mm.
- Individual cylinder diameter: 130 mm.
- Standard compression ratio A41: 16.
- Developed: 412 Nm at 1300 rpm.
- Fuel consumption: min. 1.62 kWh.
- Diesel engine cooling system A 41: liquid.
- Oil used: DS-11 in summer, DS-8 in winter.
- Motor generator: DC unit 7=G304, 214A1.
- Number of timing valves: 2
- Hydraulic pumps: 2 gear pumps, crankshaft driven by gear type transmission.
- Declared motor resource: 12 thousand hours on the latest engine models.
Where is the AMZ A-41 engine installed
This motor is equipped with excavators, graders, power plants and pumping units, other equipment in agreement with the manufacturer. Of the tractors, it is used on the T-4, DT-75M, T-4A tractors.
Overview and Features - A-41 Engine
The 90-horsepower engine has a solid cylinder capacity of 7.43 liters, which allows the base model A 41 to produce such power at relatively low speeds, about 1750. Following the trends in engine building, the developers introduced an electronic direct injection system unit into the A 41: fuel supply is fully controlled by electronics.
An important feature of the A 41 motor is a two-valve gas distribution mechanism. Engineers used it to give the engine the highest possible efficiency, output and efficiency.
To make the unit more reliable, the A 41 uses high-strength cast iron sleeves, the surface of which is surface-treated using the vertex honing method. This increases the life of the motor, coupled with a well-thought-out cooling system (however, the weight also grows). As such, an external oil-liquid heat exchanger is used, which cools the engine equally well both in idle mode and at maximum loads. By maintaining a stable and comfortable operating temperature, engine reliability has been further improved.
An interesting feature of the engine: when the engine is running, the valves are able to turn under the influence of their own springs and the vibrations accompanying the engine's work cycles. This can be attributed to the advantages of the design, since the valve stem wears out more evenly (although the chamfer of the valve disc wears out too).
The engine camshaft must withstand heavy loads, so it is hardened with high-frequency currents. The camshaft has 7 necks and 12 cams that ensure the operation of the mechanism. The assembly is driven from the crankshaft by means of a gear transmission.
The developers also took care of the environmental friendliness of the power unit: the engine that came out of the AMZ workshops complies with the domestic standard R 41.96-2005 for the absence of violations in the emission of pollutants and harmful substances.
Motor modifications
The engine is available in various variations designed to work with certain special equipment.
Main Models:
The basic engine model and modifications are installed on tractors and other equipment, in agreement with the manufacturer. In total, there are more than 11 variations of the motor, differing mainly in additional equipment. You can put:
- two hydraulic pumps;
- upgraded clutch block clutch;
- muffler;
- pneumatic compressor;
- starting electric torch heater;
- enlarged engine oil cooling system heat exchanger, etc.
Modifications of the A-41SI1, 02 and 03 engine differ from each other in the arrangement of cylinders: the latter received an in-line layout, due to which the rated power developed by the engine increased to 100 forces, and the torque margin - up to 20%, compared with counterparts. On the popular tractors of the DT-75 series, according to the catalog of the plant, motors A 41I, SI, S are installed.
Starting from 2001, during assembly, engines are assembled with their own head for individual cylinder groups, which has improved the reliability of the gas joint and reduced engine oil consumption “for waste”. In 2003, a modification was created with an electric starter, thanks to which the motor resource increased. And in 2012, the crankcase block of the A 41 engine was replaced with licensed German crankcases, which made the engine even more reliable.
crankcase:
The A-41 has a related A-01 engine, also designed to work on special equipment. Unlike the A-41, the second engine has 6 cylinders.
Maintenance
As already mentioned, A 41 and its modifications are unpretentious to working conditions and service. A qualified technician can handle routine maintenance tasks on his own.
In fact, for long and trouble-free operation of the motor, it is necessary, basically, to monitor the oil temperature and pressure in the oil line, not allowing the lubricant level to fall below a critical level, and flush. Oil change is carried out regularly, every 240 hours of engine operation.
An important regular operation is clutch adjustment, since with gradual wear of the disc linings, the retraction gaps of the middle disc and the free play of the clutch increase. Schematic clutch device using the example of one in the DT-75 tractor:
This is a double disc clutch of dry design, permanently closed type. Adjustment of the clutch DT 75 with the engine A 41 should be carried out, if necessary, according to the result of the check, approximately every 240 hours.
Over time, it may also be necessary to adjust the valves of the A 41 engine. A gap of 0.25 ... 0.3 mm is allowed for both valves of this engine.
The motor should also be serviced every shift, at the end of the shift or before it begins. The interval of the current service is about 10 hours. The set of manipulations includes:
- cleaning the engine from dirt, accumulated dust;
- checking the fasteners and the state of the tightness of the joints;
- control of the absence of extraneous noise;
- check for fuel, water and engine oil leaks.
- The engine cooling system should also be serviced regularly. The set of service operations includes:
- descaling the cooling unit, flushing the system;
- checking for leaks and sealing the weak points of the radiator, if necessary.
Typical malfunctions
The motor has some characteristic problems.
- Overheat.
As a coolant of the engine cooling system, water is mainly used, which leaves calcium deposits on the radiator cells and sediment in the tubes and cavities of the system. Therefore, you should regularly check the state of the radiator and flush it, especially if the engine is expected to operate at high loads. Sometimes, in advanced cases, it is necessary to change a failed pump or an A 41 engine thermostat that has stopped working.
- Abnormally high consumption of engine oil for waste.
The reason for this is a leaky valve cover, its own for a separate cylinder group. It is to correct this shortcoming in the new models that German-made crankcase blocks are used.
- Loss of engine power, strong vibrations during engine operation.
The likely cause is a defect in the crankshaft assembly or pistons. You should also check the balancing bearings, they tend to break down with the subsequent mandatory replacement of those.
- Poor engine start, interruptions in operation.
The reasons for this may be a malfunction of the injection system or a clogged fuel filter. You should diagnose the fuel system, clean or replace the filter, and if this operation has no effect, open the engine and check the internal components.
tuning
In some situations, the power of the A41 engine may not be enough. As in "civilian" engines, there are some technical tricks that allow you to remove increased power from the power plant.
- Turbine installation from 440 series motors.
This is a complex operation, which also requires the installation of connecting rods and a lubrication system that correspond to the new characteristics of the engine. Subject to these requirements, the motor becomes capable of delivering up to 145 forces, while maintaining the standard motor resource.
- Flashing.
Some increase can be achieved purely by software manipulation by reprogramming the electronic engine control device.
Important: at the same time, it is highly desirable to install more efficient nozzles, since regular ones may not be able to cope with the load.
In this way, 5-10 more horsepower is added to the characteristics of the A 41 engine than in the stock version.
P Checking and adjusting the gaps between the rocker arm and the valve stem is carried out on a warm and cold A-01M engine after 240 moto / h. For this you should:
1) - remove dust and remove the cylinder head caps;
2) - check the tightening of the nuts of the valve rocker racks;
3) - check the tightness of the nuts that secure the cylinder head to the block;
4) - turn on the decompressor mechanism and observe the rocker arms of the valves (sixth cylinder), while manually (slowly) rotating the crankshaft clockwise until the valves overlap, in other words, when the exhaust valve in this cylinder has not yet closed, and the intake valve has just begun open;
6) - slowly turn the crankshaft, pressing the pin until it enters the recess located on the flywheel. The piston of the first cylinder will then be in the TDC. during the compression stroke;
7) - turn off the decompressor mechanism and use a feeler gauge to check the clearance of the exhaust and intake valves of the first cylinder. If the gap is adjusted correctly, then the probe with a thickness of 0.25 mm should enter the gap with light pressure, and the probe with a thickness of 0.3 mm - with force;
8) - for adjustment, it is necessary to unscrew the lock nut of the adjusting screw and, while holding it with a wrench, screw or unscrew the adjusting screw with a screwdriver to the required clearance;
9) - upon completion of the adjustment, it is required to lock the adjusting screw with a lock nut, holding it with a screwdriver. After that, you need to check the gap again with a feeler gauge, by turning the pusher rod around the axis in order to make sure that there is no jamming;
10) - after completing the adjustment of the valve clearance of the first cylinder, proceed to the adjustment of the decompressor mechanism in this cylinder. To do this, it is necessary to install the decompressor roller in such a way that the axis of the adjusting screws is in a vertical position;
11) - select the gaps between the rocker arm and the screw, the rocker arm and the valve with the unlocked adjusting screw, and then turn the screw (clockwise) one turn, then lock the screw;
12) - upon completion of the adjustment of the decompressor mechanism in the first cylinder, remove the set screw and screw it (with a continuous part) into the hole in the flywheel housing;
13) - slowly turn the crankshaft one third of a turn, which corresponds to the end of the compression stroke in the fifth cylinder. Adjust the clearances in the valves and the decompressor mechanism of this cylinder (similar to the above);
14) - further turning the shaft by one third of a turn will allow you to adjust the clearances in the valves and the decompressor mechanism of the third, sixth, second, and also the fourth cylinder.
