The basis for dismantling and repair of the engine are: falling of engine capacity, reduction of pressure of oil, sharp increase in a consumption of oil (over 450 g on 100 km of a run), smoking of the engine, the increased fuel consumption, decrease in a compression in cylinders, and also noise and knocks.

When dismantling the engine carefully check a possibility of further application of each its detail or need of its replacement by new. Criteria according to a possibility of further use of details are given in tab. 4.8.

Maximum permissible wear of the main interfaced UMZ-4215S engine details
The interfaced details	Maximum permissible, mm		Place and way of measurement
	gaps	elasticity and conicity
Cylinder piston	0,3	-	Measure the cylinder in two mutually perpendicular directions (on an axis of a bent shaft and perpendicular to it) and in two belts (at distance of 8-10 mm and 60-65 mm) from the top plane of the block. The largest size is accepted. The piston is measured at distance of 5-10 mm from a skirt bottom in the plane, a perpendicular axis of a piston finger
Radical and conrod necks of a bent shaft - inserts	0,15	-	It is measured as it is specified in subsection <replacement of inserts of radical and conrod bearings of a bent shaft>
Radical neck of a bent shaft	-	0,07	On an axis of a bent shaft and it is perpendicular to it
Conrod neck of a bent shaft	-	0,05	The same
Axial gap of a bent shaft	0,25	-	It is measured by the probe in several places on a circle
Axial gap of the camshaft	0,25	-	The same
Axial gap of a rod	0,5	-	The same
The block of cylinders - a pusher	0,1	-	It is measured in two belts on length of a working surface
The valve - the directing plug	0,25	-	The same
Camshaft neck - the plug	0,15	-	- > -
Camshaft neck	-	0,05	- > -
Piston finger - the plug of the top head of a rod	0,1	-	It is measured in two belts on length of a working surface
Piston finger - the piston	0,1	-	The same
Plug of the top head of a rod	-	0,02	It is measured along an axis of a rod and it is perpendicular to it
Piston finger	-	0,01	The same
Piston ring - a flute in the piston (on height)	0,15	-	It is measured by the probe in several points on a circle
Piston ring - a gap in the lock	3	-	- > -

Operability of the engine can be restored by replacement of worn-out details new the nominal size or restoration of worn-out details and application of the new details of the repair size interfaced to them.

For these purposes pistons, piston rings, inserts of conrod and radical bearings of a bent shaft, a saddle of inlet and final valves, plugs of the camshaft and some other details and sets of the repair sizes are issued. The list of details and sets nominal and the repair sizes is provided in tab. 4.9.

Details and sets nominal and repair sizes of the UMZ-4215S engine
No. of a detail or set	Name	Nominal or repair size (diameter), mm
4146-1000105	Sleeve with the piston, a piston finger, lock and piston rings (a set on one cylinder)	Nominal
BK-53-1004014-14	The piston with a piston finger and lock rings assembled	92
BK-53-1004014-AP	The same, increased by 0-5 mm	92,5
VK-53-1004014-14-BR	The same, increased by 1 mm	93
BK-53-1004014-14-BP	The same, increased by 1,5 mm	93,5
414.1004015-10	Piston	92
53-1004015-ARE OF III	The piston increased by 0,5 mm	92,5
53-1004015-BR III	The same, increased by 1 mm	93
53-1004015-BP OF III	The same, increased by 1,5 mm	93,5
BK-24-1000100-10	Set of piston rings on one engine	92
BK-24-1000100-AP1	The same, increased by 0,5 mm	92,5
VK-24-1000100-BR1	The same, increased by 1 mm	93
BK-24-1000100-BP1	The same, increased by 1,5 mm	93,5
BK-53-1004023	Set of piston rings on one piston	92
BK-53-1004023-AP	The same, increased by 0,5 mm	92,5
VK-53-1004023-BR	The same, increased by 1 mm	93
BK-53-1004023-BP	The same, increased by 1,5 mm	93,5
21-1004020-14	Piston finger	25
21-1004020-20	The same, increased by 0,08 mm	25,08
21-1004020-30	The same, increased by 0,12 mm	25,12
21-1004020-40	The same, increased by 0,2 mm	25,2
BK-24-1005013-01	Bent shaft with inserts in a set	Nominal
417-1005013-01	Bent shaft with inserts in a set	Nominal
BK-24-1000104	Set of connecting rods on one engine	58
VK-24-1000104-BR	The same, reduced by 0,005 mm	57,95
BK-24-1000104-BP	The same, reduced by 0,25 mm	57,75
VK-24-1000104-DR	The same, reduced by 0,5 mm	57,5
BK-24-1000104-EP	The same, reduced by 0,75 mm	57,25
VK-24-1000104-ZHR	The same, reduced by 1 mm	57
VK-24-G000104-IR	Set of connecting rods on one engine reduced by 1,25 mm	56,75
BK-21-1000104-KP	The same, reduced by 1,5 mm	56,5
BK-53-1004060-02	Rod bolt with a nut and a lock nut assembled	Nominal
BK-24-1000102	Set of radical inserts on one engine	64
VK-24-1000102-BR	The same, reduced by 0,05 mm	63,95
BK-24-I000102-BP	The same, reduced by 0,25 mm	63,75
VK-24-1000102-DR	The same, reduced by 0,5 mm	63,5
BK-24-1000102-EP	The same, reduced by 0,75 mm	63,25
VK-24-1000102-ZHR	The same, reduced by 1 mm	63
VK-24-1000102-IR	The same, reduced by 1,25 mm	62,75
BK-24-1000102-KP	The same, reduced by 1,5 mm	62,5
BK-24-1000103	Set of plugs for the camshaft of the nominal size (semi-processed)	Nominal
21-1006024-P	The plug of the camshaft of the first neck reduced by 0,75 mm	50,46
12-1006025-RZ	The same the second neck reduced by 0,75 mm	49,46
11-6262-RZ	The same the third neck reduced to 0,75 mm	48,46
21-1006027-P	The same the fourth neck reduced to 0,75 mm	47,46
21-1006028-P	The same the fifth neck reduced to 0,75 mm	46,46
21-1007080-BP	Saddle plug-in the final valve, increased by 0,25 mm	38,75
13-1007082-BP	Saddle plug-in the final valve, increased by 0,25 mm	47,25
VK-21-1300YU1-B	Set of details for the pump of cooling liquid	-
VK-21D-1000106	Set of distributive gear wheels	-

Reduction or increase in gaps against recommended worsens conditions of lubricant of the rubbing surfaces and accelerates wear. Reduction of tightnesses in motionless (press) landings is also extremely undesirable. For such details as the directing plugs and plug-in saddles of final valves, reduction of tightnesses worsens transfer of heat from these details to walls of a head of the block of cylinders. At repair of the engine use these tab. 4.10.

Works on removal and installation of UMZ-4215S engines are generally similar specified for the ZMZ-4025,-4026 engines considered in the present manual.

Before dismantling carefully clear the engine of dirt and oil.

At an individual method of repair of the engine of a detail, suitable for further work, establish on former places where they were earned extra.

For providing it pistons, piston rings, rods, piston fingers, inserts, valves, bars, yokes and pushers at removal are marked by any of ways which is not causing damage (a kerneniye, inscribing, paint, an attachment of labels, etc.).

At any kind of repair it is impossible to razukomplektovyvat covers of rods with rods, to rearrange a case of coupling and a cover of radical bearings from one engine on another or to interchange the position of covers of average radical bearings in one block as these details are processed in common.

Fig. 4.55. Check of concentricity of an opening of a case of coupling with an axis of a bent shaft

When replacing a case of coupling check coaxiality of the opening serving for centering of the transmission with an axis of a bent shaft, and also perpendicularity of a back end face of a case of coupling concerning an axis of a bent shaft (see.

Fig. 4.56. Check of perpendicularity of a back end face of a case of coupling of an axis of a bent shaft

fig. 4.55 and 4.56 and the text to them).

Details and sets nominal and the repair sizes of the UMZ-4215S engine are given in tab. 4.9, and the sizes of the interfaced details — in tab. 4.10.

The prepared operations before assembly of UMZ-4215 engines the same, as before assembly of ZMZ-4025, ZMZ-4026 engines.

Repair of worn-out details (or their steam) is carried out by their restoration or replacement that allows to repair the block of cylinders the regrinding or replacement of sleeves, replacement of worn-out plugs of the camshaft semi-processed, with their subsequent processing under the required size, replacement of inserts of radical bearings of a bent shaft. Interface maintenance "an opening of the block of cylinders — a pusher" because of their insignificant wear comes down to replacement of pushers.

Repair and replacement of sleeves of the block of cylinders

Fig. 4.94. A stripper for a sleeve vypressovka from the cylinder block: 1 — a stripper; 2 — a sleeve; 3 — the block of cylinders

The most admissible wear of sleeves of cylinders should be considered increase in their diameter by 0,3 mm. With such wear to vypressovat a sleeve from the block of cylinders by means of a stripper of 1 (fig. 4.94) and to chisel to the closest repair size of the piston (see tab. 4.10) with the admission to processing of +0,06 mm.

Not to clamp when processing a sleeve in a cam cartridge as it will lead to deformation of a sleeve and distortion of its sizes.

To fix a sleeve in adaptation representing the plug with landing corbels with a diameter of 100 and 108 mm. To insert a sleeve into the plug against the stop in the top fillet which to clamp a laid on ring in the axial direction. After processing the mirror of the cylinder of a sleeve has to have the following deviations:

- ovality and conicity — no more than 0,01 mm, and the bigger basis of a cone has to settle down in the lower part of a sleeve;

- barrel shape and a korsetnost — no more than 0,08 mm;

- a beating of a mirror of the cylinder of rather landing corbels with a diameter of 100 and 108 mm — no more than 0,01 mm.

Fig. 4.95. Measurement of a vystupaniye of a sleeve over the block plane

After a sleeve press fitting in the block of cylinders to check the size of a vystupaniye of the top end face of a sleeve over the top plane of the block (fig. 4.95). The size of a vystupaniye has to be 0,005 — 0,055 mm.

At an insufficient vystupaniye (less than 0,005 mm) laying of a head of the block can be punched; besides, cooling liquid because of insufficient consolidation of the top corbel of a sleeve with the block of cylinders inevitably gets to the combustion chamber. When checking size of a vystupaniye of an end face of a sleeve over the block it is necessary to remove a rubber sealing ring from a sleeve.

Fig. 4.96. A clip for sleeves: 1 — a nut; 2 — a washer; 3 — the plug

That sleeves did not drop out of nests in the block at repair, to fix them by means of washers 2 and the plugs 3 which are put on hairpins of fastening of a head of the block of cylinders, as shown in fig. 4.96.

To replace the sleeves of cylinders chiseled under the third repair size of the piston after wear new.

Treat the main defects of a head of the block of cylinders which can be eliminated with repair: a prileganiye plane buckling to the block of cylinders, wear turned gray also the directing plugs of valves.

Not planeness of a surface of the head adjoining to the block at its check on a control plate the probe should not be more than 0,05 mm. To eliminate an insignificant buckling of a head (to 0,3 mm) the shabrovky plane on paint. At the buckling exceeding 0,3 mm, the head needs to be ground.

Fig. 4.97. Installation of rings on the piston: 1 — the piston; 2 — compression rings; 3 — ring disks; 4 — an axial dilator; 5 — a radial dilator; 6 — a temperature-controlled insert

Replace piston rings (fig. 4.97) through 70 000 — 90 000 km of a run (depending on car service conditions).

Piston rings establish on three on each piston: two compression and one oil scraper. Compression rings are cast from special cast iron. The external surface of the top compression ring is covered with porous chrome, and the surface of the second compression ring has to be covered with tin or a fosfatirovana.

On internal cylindrical surfaces of both compression rings pro-points at the expense of which rings after their installation into position are a little unscrewed are provided. It improves and accelerates them to extra earnings to cylinders. Rings need to be installed on the piston by pro-points up, towards the bottom.

The oil scraper ring — compound, has two ring disks, radial and axial dilators. The external surface of disks of oil scraper rings is covered with solid chrome.

Lock of rings of a straight line.

Piston rings of the repair sizes (see tab. 4.9) differ from rings of the nominal sizes only in outer diameter.

Rings of the repair size can be installed in worn-out cylinders with the next smaller repair size by a podpilivaniye of their joints before receiving a gap in the lock 0,3 — 0,5 mm.

Fig. 4.63. Selection of piston rings to the cylinder

To make check of a gap in a joint of a ring, as shown in fig. 4.63. To repolished cylinders to adjust rings by the top part, and to worn out — on the lower part of the cylinder (within the course of piston rings). At a bringing of a ring to install in the cylinder in working situation, i.e. in the plane, a perpendicular axis of the cylinder for what to advance it in the cylinder by means of a piston head. The planes of joints at the compressed ring have to be parallel.

Fig. 4.52. Removal of piston rings from the piston

To remove and install rings on the piston by means of adaptation (see fig. 4.52) to model 55-1122.

Fig. 4.64. Check of a side gap between a piston ring and a flute in the piston

After adjustment of rings on cylinders to check a gap between rings and flutes in the piston (see fig. 4.64) which has to be: for the top compression ring — 0,050 — 0,082 mm, for lower compression — 0,035 — 0,067 mm. At big gaps replacement only of piston rings will not exclude the raised oil consumption because of intensive transfer by its rings in space over the piston. In this case along with replacement of rings it is necessary to replace also pistons (see. "Replacement of pistons"). Simultaneous replacement of piston rings and pistons sharply cuts an oil consumption.

Fig. 4.59. Cleaning of a deposit in flutes of pistons

When replacing only of piston rings without replacement of pistons to remove a deposit from the bottoms of pistons, from ring flutes in the head of the piston and maslootvodyashchy openings located in flutes for oil scraper rings. To delete a deposit from flutes carefully not to damage their side surfaces, by means of adaptation (see fig. 4.59).

To delete a deposit from maslootvodyashchy openings with a drill with a diameter of 3 mm.

When using sleeves of cylinders, new or repolished under the repair size, it is necessary that the top compression ring had the chromeplated covering, and other rings were tinned or fosfatirovanny. If the sleeve is not under repair, and only piston rings change, then all of them have to be tinned or fosfatirovanny as to a worn-out sleeve the chromeplated ring is earned extra very badly.

Before installation of pistons in cylinders to part joints of piston rings at an angle 120 ° to each other. After replacement of piston rings in the first 1000 km of a run not to exceed the speed of 45 — 50 km/h.

It is necessary to replace pistons at wear of a flute of the top piston ring or a skirt of the piston. To install pistons of the same size in partially worn-out cylinders (nominal or repair) what the pistons which were earlier working in this engine had. However it is desirable to pick up a set of the bigger size of pistons for reduction of a gap between a skirt of the piston and a mirror of the cylinder.

In this case a gap between a skirt of the piston and a mirror of the cylinder to check in lower, the least worn-out, parts of the cylinder.

Not to allow reduction of a gap in this part of the cylinder less than 0,02 mm.

In spare parts pistons together with the piston fingers and lock rings which are picked up to them are delivered (see tab. 4.9).

For selection pistons of the nominal size sort by the outer diameter of a skirt. On the bottoms of pistons alphabetic references of dimensional group which are specified in tab. 4.11 are beaten out.

Dimensional groups of pistons
Designation of dimensional group	Maximum deviations, mm
And	0.000 - 0.012
B	+0.012 0.000
In	+0.024 +0.012
	+0.036 +0.024
Д	+0.048 +0.036

On pistons of the repair sizes also the size of their diameter is beaten out.

Except selection of pistons to cylinder sleeves on diameter of a skirt, they are selected also for weight. The difference in weight between the easiest and heaviest piston for one engine should not exceed 4 g.

At assembly to install pistons in sleeves of the same group.

Fig. 4.65. Installation of the piston with rings in the cylinder by means of a mandrel

To install pistons in cylinders by means of model 59 adaptation — 85, shown in fig. 4.65.

At installation of pistons the tag "before" cast on the piston has to be turned into cylinders to a forward part of the engine, on the piston with a cutting skirt a tag "back" — towards a coupling case.

On all pistons of the repair sizes of an opening in lugs under a piston finger become the nominal size with breakdown on groups. If necessary these openings are chiseled or developed to the next repair size with the admission. Conicity and ovality of an opening — no more than 0,0025 mm. When processing to provide perpendicularity of an axis of an opening to a piston axis, a permissible deviation — no more than 0,04 mm on length of 100 mm.

Repair of rods comes down to replacement of the plug of the top head and its subsequent processing under a piston finger of the nominal size or to processing of the plug which is available in a rod under a finger of the repair size.

In spare parts the plugs of one size manufactured of the bronze film OTsS4-4-2,5 1 mm thick are delivered.

At a press fitting of the new plug in a rod to provide coincidence of an opening in the plug with an opening in the top head of a rod. Openings serve for supply of lubricant to a piston finger.

After a press fitting of the plug to condense its internal surface with a smooth brooch to diameter of 24,3+0,045 mm, and then to develop or chisel under the nominal or repair size with the admission of mm.

For example, the plug to develop or chisel under a finger of the nominal size to diameter of 25 mm or under a finger of the repair size to diameter of 25,20 mm.

The distance between axes of openings of the lower and top heads of a rod has to be (168±0,05) mm; admissible not parallelism of axes in two mutually perpendicular planes on length of 100 mm has to be no more than 0,04 mm; ovality and conicity should not exceed 0,005 mm. To sustain the specified sizes and admissions, it is necessary to deploy the plug of the top head of a rod in the conductor.

Fig. 4.98. Operational development of an opening in the top head of a rod: 1 — a derzhavka; 2 — a grinding head; 3 — a clip

After expansion to make operational development of an opening on a special grinding head, holding a rod in hand (fig. 4.98). To establish grinding whetstones of a head by the micrometric screw on the required repair size.

Rods which openings under inserts in the lower head have ovality more than 0,05 mm are subject to replacement.

The repair sizes of piston fingers and number of sets are specified in tab. 4.9.

The piston fingers increased on diameter by 0,08 mm are applied to replacement of piston fingers without preliminary processing of openings in the piston and in the top head of a rod. Application of the fingers increased by 0,12 mm and 0,20 mm demands preliminary processing of openings in lugs of the piston and in the top head of a rod as it is described above (see. "Replacement of pistons" and "Repair of rods").

Fig. 4.53. Vypressovka of a piston finger from the piston a stripper: 1 — the piston; 2 — a piston finger; 3 — a mandrel; 4 — the stripper screw

Fig. 4.99. Removal of a lock ring of a piston finger

Fig. 4.62. A press fitting of a piston finger in the piston and a rod: 1 — the piston; 2 — a rod; 3 — a mandrel; 4 — a piston finger; 5 — a thrust bearing; 6 — the screw

Before a vypressovka of a piston finger take from the piston lock rings of a piston finger flat-nose pliers, as shown in fig. 4.99. Vypressovka and a press fitting of a finger to make on devices, as shown in fig. 4.53 and 4.62. Before a vypressovka of a finger to heat the piston in hot water to 70 °C.

Repair of piston fingers consists in their regrinding from the big repair sizes on smaller or in chromium plating with the subsequent processing under the nominal or repair size.

The fingers having breaks, vykrashivaniye and cracks of any size and an arrangement, and also overheat traces (color of a pobezhalost) are not subject to repair.

Fig. 4.61. Selection of a piston finger to a rod

Piston finger to the top head of a rod to select 0,0045 — 0,0095 mm with a gap. At the normal room temperature the finger has to move smoothly in an opening of the top head of a rod from effort of a thumb of a hand (see fig. 4.61). The piston finger at the same time has to be slightly oiled by low-viscous.

To install a finger in the piston with a tightness 0,0025 — 0,0075 mm. Almost piston finger is selected so that at the normal room temperature (20 °C) it did not enter the piston from effort of a hand, and when heating the piston in hot water up to the temperature of 70 °C would enter it freely. Therefore before assembly to heat the piston in hot water to 70 °C. The finger press fitting without preliminary heating of the piston will lead to damage of a surface of openings in piston lugs, and also to deformation of the piston.

For ensuring the correct balancing of the engine the difference in the weight of the pistons installed in the engine assembled with rods should not exceed 8 g.

Lock rings of a piston finger have to sit in the flutes with a small tightness.

Prevention Do not apply the rings which were in the use.

To install piston rings on the piston as it is specified in the subsection "Replacement of Piston Rings".

Considering complexity of selection of a piston finger to the piston and a rod (for ensuring nominal landings), pistons are delivered in the spare part assembled with a piston finger, lock and piston rings.

Repair of a bent shaft consists in regrinding of radical and conrod necks under the next repair size.

The repair sizes of conrod and radical necks are defined by the sizes of sets of the connecting and radical rods delivered in spare parts which are given in tab. 4.9.

Radial gaps in conrod and radical bearings of a bent shaft have to be 0,020 — 0,049 mm and 0,020 — 0,066 mm respectively. To make regrinding of necks with the admission 0,013 mm.

If the sizes of conrod and radical necks do not coincide among themselves, it is necessary to pereshlifovat them under one repair size.

Facets and openings of the forward and back ends of a bent shaft are not suitable for installation in the grinder. For this purpose to make the removable centers glasses. To napressovyvat the forward center on a neck with a diameter of 38 mm, and back to align (diameter of 122 mm) of a shaft on the outer diameter of a flange and to fix to it bolts. At production of the transitional centers to provide concentricity of center and adjusting openings. Without meeting this condition, it is impossible to provide necessary concentricity of seats of a flywheel and a gear wheel to axes of radical necks. When grinding conrod necks to establish a shaft on the additional centers, coaxial axes of conrod necks. For this purpose it is possible to use the centers glasses, having provided on them flanges with two additional center openings remote from an average opening on (46±0,05) mm.

For the forward end it is better to make the new center flange which is established on a neck with a diameter of 40 mm (on a spline) and in addition fastens a bolt (ratchet) screwed in a carving opening.

Before grinding of necks to deepen facets on edges of oil channels so that their width after removal of all allowance for grinding was 0,84,2 mm. To do it by means of an emery stone with a corner at top 60 — 90 °, brought into rotation by the electric drill.

When grinding conrod necks it is not necessary to concern a grinding wheel of side surfaces of necks not to break an axial gap of rods. Radius of transition to a side surface to maintain 3,5 mm. To make grinding plentiful cooling with an emulsion.

In the course of regrinding the following sizes have to be sustained:

- distance between axes of radical and conrod necks — (46±0,05) mm;

- a conicity, barrel shape, saddle shape, ovality and a facet of necks — no more than 0,005 mm;

- an angular arrangement of conrod necks — ±0 ° 10';

- not parallelism of axes of conrod necks with an axis of radical necks — no more than 0,012 mm on all length of a conrod neck;

- a beating (at installation of a shaft extreme radical necks on prisms) average radical necks — no more than 0,02 mm, a neck under a distributive gear wheel — to 0,03 mm, and a neck under a nave of a pulley and a back epiploon — to 0,04 mm.

After grinding of necks to wash out a bent shaft, and to clear oil channels of an abrasive and resinous deposits. At the same time to turn out traffic jams of mud-catchers. After cleaning of mud-catchers and channels to wrap traffic jams into place again and to zakernit each of them from a spontaneous vyvertyvaniye.

To clear oil channels also at operational repair of the engine when the bent shaft is taken out from the block.

After repair the bent shaft gathers with the same flywheel and coupling which stood before repair.

Fig. 4.100. A mandrel for installation of the conducted clutch plate

At installation it is necessary to center the conducted disk in relation to an axis of a bent shaft. For this purpose to insert a special mandrel (fig. 4.100) into a shlitsevy opening of the conducted disk so that its end entered an opening of the ball bearing in cranked to a shaft. It is necessary to tighten fastening bolts to a flywheel evenly in order to avoid break of bolts.

Before installation on the engine assembled dynamically to balance a bent shaft with coupling on the special machine. Previously to center the conducted clutch plate by means of a shaft of the transmission or a special mandrel.

To eliminate an imbalance with drilling of metal in a flywheel rim on the radius of 158 mm a drill with a diameter of 12 mm. Depth of drilling should not exceed 12 mm. An admissible imbalance — no more than 70 g · see.

In spare parts inserts of radical and conrod bearings nominal and seven repair sizes which are specified in tab. 4.9 are delivered. Inserts of the repair sizes differ from inserts of the nominal size in the internal diameter reduced on 0,05; 0,25; 0,50; 0,75; 1,0; 1,25 and 1,50 mm.

Inserts of radical and conrod bearings are replaced without any adjustment.

Depending on wear of necks at the first change of inserts to apply inserts nominal or, as a last resort, the first repair size (reduced by 0,05 mm).

And the subsequent repair sizes to install inserts of the second in the engine only after regrinding of necks of a bent shaft.

If as a result of repeated regrindings diameters of necks of a bent shaft are reduced so that inserts of the last repair size will be unsuitable for it, then it is necessary to assemble the engine with a new shaft.

The radial gap in conrod and radical bearings of a bent shaft has to be respectively 0,020 — 0,049 mm and 0,020 — 0,066 mm.

To make check of size of radial gaps by means of a set of the control probes executed from a copper foil 0,025 thick; 0,05; 0,075 and 0,1 mm cut in the form of strips 6 — 7 mm wide and a little less than width of insert long. Edges of probes have to be protected for an exception of damage of a surface of an insert.

To make check of a radial gap in the following order:

- to uncover with checked necks with an insert and to put previously oiled control probe 0,025 mm thick across an insert;

- to establish into place a cover with an insert and to tighten bolts, at the same time bolts of other covers have to be released;

- to turn a bent shaft a hand on a corner no more than on 60 — 90 ° in order to avoid damage of a surface of an insert by the probe.

If the shaft is turned too easily, the gap more than 0,025 mm means. In this case to repeat check by probes 0,05; 0,075 mm etc. until it becomes impossible to turn a bent shaft.

Probe thickness at which the shaft is turned with notable effort is considered to the equal actual size of a gap between an insert and a neck of a bent shaft.

When replacing inserts to observe the following:

- to replace inserts without subracing operations;

- to watch that the fixing ledges on joints of inserts freely (from effort of a hand) entered grooves in shaft beds;

- along with replacement of inserts to clear mud-catchers in conrod necks.

Replacement of connecting rods can be made, without removing the engine from the car chassis. To make replacement of radical inserts on the engine removed from the car.

After replacement of inserts to roll the engine (see. "Engine running in after repair").

If when replacing inserts the engine was not removed from the car, then at the first 1000 km of a run speed should not exceed 50 km/h.

Fig. 4.88. Forward end of a bent shaft: 1 — a nave; 2 — a bent shaft; 3 — a bolt; 4 — an epiploon; 5 — a fan drive pulley; 6 — a damper; 7 — a persistent washer; 8 — a forward washer; 9 — a back washer; 10 — a pin

Along with replacement of inserts to check an axial gap in the persistent bearing of a bent shaft which has to be 0,075 — 0,175 mm. If an axial gap more than 0,175 mm to replace washers 8 (see fig. 4.88) and 9 new. The forward washer is made four sizes on thickness: 2,350 — 2,375; 2,375 — 2,400; 2,400 — 2,425; 2,425 — 2,450 mm.

Fig. 4.101. Check of an axial gap of a bent shaft

For check of a gap in the persistent bearing to put the screw-driver (fig. 4.101) between the first crank of a shaft and a forward wall of the block and to wring out a shaft to a back end face of the engine. Then to determine by the probe a gap between an end face of a back washer of the persistent bearing and the plane of a burt of the first radical neck.

Before installation of inserts to check coaxiality of radical necks of a bent shaft. For this purpose to establish a bent shaft in the centers and to check the provision of axes of radical necks according to indications of the indicator.

Fig. 4.89. Back end of a bent shaft: 1 — the block; 2 — an epiploon; 3 — a bent shaft; 4 — a flywheel; 5 — the bearing; 6 — an oil case; 7 — a coupling case; 8 — consolidation of a case of coupling; 9 — the holder of an epiploon

The forward and back ends of a bent shaft are condensed with epiploons (see fig. 4.88 and 4.89).

To make restoration of necessary gaps in plugs of the camshaft regrinding of basic necks of a shaft, reducing their size no more than by 0,75 mm, and replacement of worn-out plugs semi-processed with the subsequent their boring for the sizes of repolished necks.

Before regrinding of necks of the camshaft to deepen flutes on the first and last necks at a size of reduction of diameter of these necks in order that after regrinding of necks to provide intake of lubricant to distributive gear wheels and to an axis of yokes. Grinding of necks you carry out in the centers with the admission 0,02 mm. After grinding of a neck polish.

Vypressovka and a press fitting of plugs it is more convenient to do by means of carving hairpins (the corresponding length) with nuts and podkladny washers.

The semi-processed camshaft plugs delivered in spare parts by a set on one engine have the sizes of outer diameter same, as well as plugs of the nominal size therefore they are pressed in block openings without preliminary processing.

For ensuring sufficient thickness of a layer of babbit (antifrictional material) the size of repair reduction of internal diameter of all plugs has to be identical.

At a press fitting of plugs to monitor coincidence of their side openings to oil channels in the block. To chisel plugs, reducing diameter of each subsequent plug, beginning from a forward end face of the block, on 1 mm. To conduct boring with the admission of mm that gaps in plugs after installation of a shaft corresponded to these tab. 4.10.

When boring plugs to sustain distance between axes of openings under cranked and distributive shaft (118±0,025) mm. To check this size at a forward end face of the block. The deviation from coaxiality of openings in plugs has to be no more than 0,04 mm, and the deviation from parallelism of cranked and distributive shaft has to be no more than 0,04 mm on all length of the block. To provide coaxiality of plugs in the set limits, to process them at the same time by means of long and rather rigid borshtanga with the cutters or development got on it on number of support. To establish a borshtanga, being based concerning openings for inserts of radical bearings.

To smooth out camshaft cams at insignificant wear and teases a grinding skin: at first coarse-grained, and then fine-grained. At the same time the grinding skin has to cover not less than a half of a profile of a cam and have some tension that will provide the smallest distortion of a profile of a cam.

At wear of cams on height more than to replace the camshaft with 0,5 mm new.

To check curvature of the camshaft the indicator on napes (on a cylindrical surface) inlet and final cams of the second and third cylinders. At the same time to establish a shaft in the centers. If the beating of a shaft exceeds 0,03 mm, then a shaft to correct or replace.

Violation of tightness of valves at the correct thermal gaps between cores of valves and yokes, and also during the correct operation of the carburetor and system of ignition is found on characteristic cottons from the muffler and the carburetor. The engine at the same time works with interruptions and does not develop full capacity.

To carry out restoration of tightness of valves grinding in of working facets of valves to their saddles. In the presence on working facets of valves and saddles of sinks, ring developments or рисок which cannot be removed grinding in, to proshlifovat facets with the subsequent grinding in of valves to saddles. To replace valves with the jarred-on heads.

Fig. 4.102. Grinding in of valves

To grind in facets of valves a pneumatic or electric drill of the GARO model 2213, 2447 or manually by means of rotation. To make grinding in returnable rotary motions at which the valve is turned in one party slightly more, than in another. For the period of grinding in under the valve to establish a squeezing spring with small elasticity. Internal diameter of a spring has to be about 10 mm. The spring has to raise several the valve over a saddle, and by easy pressing the valve has to sit down on a saddle. Contact of the tool with the valve is carried out by a rubber prisos, as shown in fig. 4.102. For the best coupling of a prisos with the valve of their surface have to be dry and pure.

For acceleration of grinding in to use the pritirochny paste made of one part of micropowder of the M20 brand and two parts of engine oil. Carefully to mix mix before application. Grinding in of a message before emergence on working surfaces of a saddle and a plate of the valve of a uniform opaque facet on all circle. By the end of grinding in to reduce the content of micropowder in pritirochny paste. To finish grinding in on one pure oil. Instead of pritirochny paste it is possible to use the emery powder No. 00 mixed with engine oil.

It is recommended to use GARO R-108 or OPR-1841 grinders to grinding of working facets of valves. At the same time to clamp a core of the valve in the aligning boss of the machine installed at an angle 44 ° 30' to a working surface of a grinding stone. Reduction on 30' a tilt angle of a working facet of a head of the valve in comparison with a corner of a facet of saddles accelerates to extra earnings and improves tightness of valves. When grinding to remove the minimum quantity of metal from a valve head facet. Height of a cylindrical corbel of a working facet of a head of the valve after grinding has to be not less than 0,7 mm, and coaxiality of a working facet concerning a core — within 0,03 mm of the general indications of the indicator. A valve core beating — no more than 0,02 mm. To replace valves with a big beating new. Not to pereshlifovyvat valve cores on the smaller size as there will be a need for production of new croutons of plates of valvate springs.

Fig. 4.103. Device for grinding of saddles of valves: 1 — the cutting plug; 2 — a mandrel; 3 — a grinding wheel; 4 — a lead washer; 5 — the directing plug; 6 — the head case; 7 — a pin; 8 — a lead; 9 — a tip; 10 — a flexible shaft; 11 — an electric motor shaft; 12 — the electric motor

To grind facets of saddles at an angle 45 ° it is coaxial to an opening in the plug. Width of a facet has to be 1,6 — 2,4 mm. It is recommended to use adaptation represented in fig. 4.103 to grinding of saddles. To grind a saddle without pritirochny paste or oil until the stone does not begin to process all working surface.

After rough processing to replace a stone with fine-grained and to make fair grinding of a saddle. The facet beating concerning an axis of an opening of the plug of the valve should not exceed 0,03 mm. To replace worn-out saddles new. In spare parts the saddles of valves having outer diameter are delivered it is more nominal on 0,25 mm. To take worn-out saddles from a head by means of a vertical drill.

After extraction of saddles to chisel in a nest head for the final valve to diameter of 38,75+0,025 mm and for the inlet valve — to diameter of 49,25+0,025 mm. Before a press fitting of saddles to heat a head of the block of cylinders to temperature of 170 °C, and to cool saddles with artificial ice. To make a press fitting quickly, without giving the chance to saddles to heat up. The cooled-down head densely covers saddles. For increase in durability of landing of saddles to fuller them on outer diameter by means of a flat mandrel, trying to obtain filling of a facet of a saddle. Then to proshlifovat to the required sizes and to grind in.

If wear of a core of the valve and a guide of the plug is so big that the gap in their joint exceeds 0,25 mm, then tightness of the valve restores only after replacement of the valve and its plug. In spare parts valves only of the nominal sizes, and the directing plugs — with the internal diameter reduced by 0,3 mm for the subsequent their development under the final size after a press fitting in a head of the block of cylinders are delivered.

To develop the pressed plugs to diameter of 9+0,022 mm. The core of the inlet valve has diameter of 9 mm, final — 9 mm, therefore, gaps between cores of inlet and final valves and plugs have to be respectively equal 0,050 — 0,097 mm and 0,075 — 0,117 mm.

Fig. 4.104. Drift of plugs of valves: And — to temper the specified surface

To press off the worn-out directing plugs from a head of the block of cylinders by means of a drift (fig. 4.104).

To press the new plug from yokes by means of the same drift against the stop in the lock ring which is available on the plug. At the same time to heat a head of the block of cylinders to temperature of 170 °C, and to cool the plug with artificial ice.

After replacement of plugs of valves to make grinding of saddles (being aligned on openings in plugs) and then to grind in to them valves. After grinding of saddles and grinding in of valves all channels and places where the abrasive could get, carefully wash out and blow compressed air.

Plugs of valves — ceramic-metal, porous. After final processing and washing to impregnate them with oil. For this purpose to insert into each plug at several o'clock the felt match impregnated in a spindle oil. To grease cores of valves before assembly with a thin layer of the mix prepared from seven parts of oil colloidal and graphitic medicine and three parts of engine oil.

Can be the possible malfunctions of valvate springs appearing in use: elasticity reduction, fiascos or cracks on rounds.

To check elasticity of valvate springs when dismantling the valvate mechanism. The effort necessary for compression of a new valvate spring to 46 mm on height, has to be 267 — 310 N (27,3 — 31,7 kgfs), and to 37 mm — 686 — 784 N (70 — 80 kgfs). If effort of compression of a spring to 46 mm on height less than 235 N (24 kgfs), and to 37 mm — less than 558,6 N (57 kgfs), then such spring to replace new.

To replace springs with fiascos, cracks and traces of corrosion new.

The directing openings in the block under pushers wear out slightly therefore the nominal gap in this interface is restored by replacement of worn-out pushers with new. In spare parts pushers only of the nominal size are delivered.

Pushers approach openings with a gap of 0,040 — 0,015 mm. Pushers depending on the size of outer diameter are broken into two groups and are marked by a branding: in figure 1 — with a diameter of 25 mm and figure 2 — with a diameter of 25 mm. Correctly picked up pusher oiled by liquid mineral has to fall smoothly under own weight to a nest of the block and it is easy to be turned in it.

To replace the pushers having at end faces of plates beam teases, wear or a vykrashivaniye of a working surface new.

Fig. 4.105. Drive of the oil pump and sensor distributor of ignition: provision of a cut of the roller: And — on the drive installed on the engine; B — on the drive before its installation on the engine; In — on the roller of the oil pump before installation of the drive on the engine; 1 — the roller of the oil pump; 2 — the plug; 3 — the intermediate roller plate; 4 — a pin; 5 — a drive gear wheel; 6 — a camshaft gear wheel; 7 — a persistent washer; 8 — the block of cylinders; 9 — laying; 10 — the drive roller; 11 — the drive case; 12 — the ignition sensor distributor drive

The roller 10 (fig. 4.105) of the drive of the distributor which is worn out on diameter is restored by chromium plating with the subsequent grinding to diameter of 13-0,011 mm.

To replace the gear wheel of the 5th drive of the oil pump and sensor distributor of ignition having fiascos, vykrashivaniye or considerable developments of a surface of teeths, and also wear of an opening under a pin to the size more than 4,2 mm new.

For replacement of the roller or a gear wheel of the drive of the sensor distributor to remove a gear wheel from the roller, having taken out previously a gear wheel pin with the help a small beard with a diameter of 3 mm. At removal of a gear wheel from the roller to install the case 11 of the drive by the top end face on a support with an opening in it for pass of the roller of the drive assembled with the persistent plug. You make assembly of the drive taking into account the following:

- at installation of the roller (assembled with the persistent plug) in the case of the drive of the sensor distributor to oil the roller engine;

Fig. 4.106. The provision of a gear wheel of the drive on the roller: 1 — a gear wheel tooth end face; 2 — the axis passing through the middle of hollows of teeths

- having connected the drive roller 10 to the intermediate roller plate 3 drives and having put on a persistent washer 7, to napressovat a gear wheel on the roller, having sustained a gap of "" (fig. 4.106) between a persistent washer and a gear wheel of the drive of 0,25-0,15 mm.

At the same time it is necessary that axis 0 — 0, passing through the middle of hollows between two teeths at an end face of B, was displaced concerning an axis V-in a roller vent on 5 °30±1 °;

- an opening in a gear wheel and the roller under a pin to drill diameter (4±0,037) mm, maintaining distance from an opening axis to an end face of a gear wheel (18,8±0,15) mm.

When drilling an opening and at installation of a gap between a persistent washer and a gear wheel the sensor distributor drive roller assembled with the persistent plug has to be pressed to the drive case in the direction of the oil pump. The pin connecting the roller to a gear wheel has to have a diameter of 4-0,025 with a length of 22 mm.

In the assembled drive of the sensor distributor its roller has to be turned freely by hand.

At big wear of details of the oil pump pressure in lubricant system goes down and noise appears.

When dismantling the pump to check elasticity of a spring of the reducing valve. Elasticity of a spring is considered sufficient if for compression it to 24 mm on height it is necessary to make effort (54±2,45) N (5,5±0,25) kgfs.

Repair of the oil pump usually consists in grinding of end faces of covers, replacement of gear wheels and laying.

When dismantling the pump previously to drill a rasklepanny head of a pin of fastening of the plug 2 (see fig. 4.105) on its roller 1, to beat out a pin, to remove the plug and a cover of the pump. After that to take out the pump roller together with the leading gear wheel from the case towards its cover.

In case of dismantling of the leading gear wheel and the roller to drill a pin a drill with a diameter of 3 mm.

The conducting and conducted gear wheels with the painted teeths, and also with noticeable developments of a surface of teeths to replace new. The conducting and conducted gear wheels established in a pump housing have to be turned easily by hand for the leading roller.

If on the internal plane of a cover there is considerable (more than 0,05 mm) a development from end faces of gear wheels, it should be proshlifovat.

Between a cover, a plate and a pump housing paronitovy laying 0,3 — 0,4 mm thick is established.

Use of shellac, paint or other pressurizing substances at laying installation, and also installation of thicker laying are not allowed as it causes reduction of giving of the pump.

To make assembly of the pump taking into account the following:

Fig. 4.107. Fastening of the plug on the roller of the oil pump

- to napressovat the plug on the leading roller, having sustained the size between an end face of the leading roller and an end face of the plug of 8 mm (fig. 4.107). At the same time the gap between a pump housing and other end face of the plug has to be not less than 0,5 mm;

- to drill in the leading roller and in the plug an opening with a diameter of 4 mm, maintaining the size of (20±0,25) mm.

- to razzenkovat an opening on both sides on depth of 0,5 mm at an angle 90 °, to press in it a pin with a diameter of 4-0,048 mm and 19 mm long and to rasklepat it from two parties.

If operability of the pump by means of repair cannot be restored, then it is necessary to replace it new.

To make installation of the drive of the oil pump and sensor distributor of ignition on the block in the following order:

- to turn out a candle of the first cylinder;

- to establish in an opening for a candle компрессометр and to turn the starting handle a bent shaft prior to the movement of an arrow. It will occur at the beginning of a compression step in the first cylinder. It is possible to stop up an opening for a candle with a paper pyzh or a thumb of a hand. In this case at a step of compression will jump out пыж or the air outlet from under a finger will be felt;

- having convinced that compression began, carefully to turn a bent shaft before coincidence of an opening on a rim of a pulley of a bent shaft with the index (pin) on a cover of distributive gear wheels;

- to turn the drive roller that the cut at its end face for a thorn of the distributor was located as it is specified fig. of 4.105 B, and to turn the roller of the oil pump by means of the screw-driver in the situation specified fig. 4.105 B;

- carefully, without touching with a gear wheel block walls, to insert the drive into the block. After installation of the drive to the place of its roller has to reach the position specified fig. 4.105 A.

Fig. 4.108. A mandrel for centering of the oil pump

For reduction of wear in hinged connections of the drive to install the pump coaxially to an opening for the drive. For this purpose use the mandrel (fig. 4.108) which is densely entering an opening for the drive in the block and having a cylindrical shaft with a diameter of 13 mm. To center the pump on a shaft of a mandrel and to enshrine in this provision.

Repair of separate knots and systems of the engine

Repair of the pump of the cooling system, repair of knots of power supply systems is similar to the works for ZMZ-4025,-4026 engines specified in the present manual except for the following:

Fig. 4.109. The provision of a head of the fuel pump at its installation

— the provision of a head of the fuel pump at its installation has to correspond to fig. 4.109