All-mode, centrifugal type, changes the fuel supply depending on the load, maintaining the engine speed set by the driver

Mounted at the rear of the high pressure fuel pump and driven by a camshaft via gears.

A drive gear 20 is mounted on the cone of the camshaft.

The rotation from the pump shaft to the drive gear is transmitted through rubber crackers 19.

The driven gear is made as one piece with the shaft 16 of the load holder and is installed in the cup 15 on two ball bearings.

A weight holder 7 is pressed onto the roller 16, on the axes of which weights 22 swing.

The loads with their rollers rest against the end of the clutch 27, which, through the thrust bearing and the heel 37, transmits the force of the loads to the power lever 43, suspended together with the two-arm lever 5 on the axle 11.

MAZ injection pump regulator

The clutch with the thrust heel assembly rests at one end through 27 balls on the guide surface of the holder, and at the other end is suspended on the earring 39, fixed on the power lever 43.

The heel of the regulator is connected by a common axis with the lever 35 of the rail and through the rod 13 with the rail 12 of the fuel pump.

A spring 24 of the rack lever is attached to the upper part of the rack lever, and a pin is pressed into the lower part, which enters the groove of the backstage 34.

Shaft 25 is rigidly connected to control lever 2 and spring lever 8.

The spring 6 of the regulator is hooked to the spring lever and the two-arm lever 5, the force of which is transmitted from the two-arm lever to the power lever through the adjusting screw 3.

The power lever has an adjusting bolt 40, which rests against the governor lever shaft.

The engine speed is set by control lever 2, which is connected to the fuel supply control pedal by means of rods.

When you press the pedal, the lever 2 turns at a certain angle and through the lever 8 rigidly connected to it causes an increase in the tension of the spring 6, under the action of which the rail moves in the direction of increasing the fuel supply and the engine crankshaft speed increases.

This happens until the centrifugal force of the weights balances the tension force of the spring 6, i.e. until a stable engine operation mode is established.

Regulator repair

The crankshaft speed controller should not be completely disassembled during repairs.

The load holder assembly is not dismantled unnecessarily, since parts can be damaged during pressing out.

In addition (even in the case of disassembly), it is required to strictly observe the completeness of the goods, selected according to the static moment.

Repair of MAZ injection pump regulator

The speed controller is disassembled in the following sequence: remove the inspection hatch cover, disconnect the spring 38 from the rack lever with tweezers, disconnect the spring bar from the rail 40 of the injection pump and remove the cover 2 of the regulator.

When removing the cover, it is necessary to protect the balls 29 located in the trapezoidal groove of the weight coupling from loss.

Having unscrewed the cup fastening bolts 37, remove the cup together with the weight holder and weights 30.

Removal and unstacking of goods is not allowed.

After that, unscrew the gear mounting nut and remove gear 32 with flange 31 and crackers 33 from the gear bushing, remove the bushing from the fuel pump cam roller with a puller (Fig. 3).

Repair of MAZ injection pump regulator

The regulator cover must be disassembled in the following order: unscrew the screws of the plug, remove the axle 41 (see Fig. 1) of the levers, remove the lever 9 of the regulator with the clutch 28 of the weights and the lever 17 of the rail, disconnect the two-arm lever 6 from the spring 5 of the regulator, remove the spring , unscrew the bolt and the axis of the yoke bracket and remove the yoke 18 and the yoke bracket 14, take out the shaft 27 of the spring lever together with the regulator control lever, after loosening the spring lever fastening bolt, moving the spring lever along the shaft and removing the key.

To disassemble the backstage, it is necessary to turn the axis 22 relative to the backstage 18, thereby drowning the latch 20. Insert a plate 1.5 - 2 mm thick into the resulting gap between the end face of the latch and the cutout of the axis and, having turned the axis to its original position, remove it.

To disassemble the cup assembly with the shaft of the weight holder, it is necessary to turn the spring ring and remove the shaft 36 of the weight holder assembly with the holder and bearings from the glass, press the front (small) bearing from the shaft.

Compressing the rear bearing weight holder from the roller, as well as disassembling the weights unnecessarily, is not recommended. When removing loads, they must be installed

enes again in the same sequence.

The weight holder assembly must be inspected and measured without disassembly to determine suitability for further operation.

The gap in engagement between the teeth of the holder shaft and the drive gear should not exceed 0.25 mm at a nominal value of 0.085 mm.

Checking is carried out when installing parts at their workplaces.

The gap between the bushings of the weights and the axes of the weights pressed into the holder should not exceed 0.24 mm at a nominal value of 0.035 mm.

The gap between the load roller, which transmits force to the coupling, and the roller axis is not more than 0.3 mm, at the nominal value - 0.025 mm.

The outer diameter of the weight roller must be at least 15.8 mm.

The weight holder is made of steel 20 L. The neck for the balls of the weight coupling is carburized to a depth of 0.2 - 0.6 mm and hardened with heating to a hardness of at least HRC56. Casting hardness HB 121 – 187.

The main defects that occur during operation are as follows: wear of the neck for the balls of the load coupling and wear of the holes for the axles of the loads.

The neck for the balls of the cargo coupling is restored when it is worn to a diameter of less than 23.86 mm by chromium plating. To do this, grind the neck cleanly and chrome to a diameter of 24.15-0.02 mm

After final grinding on a length of 18 mm, there should be a size of 24.15-0.02 mm and a surface roughness of 0.32 microns.

The size of the holes for the axis of the loads is restored by setting bushings. To do this, the holes are drilled and deployed along the conductor to a diameter of 10 + 0.010 over a length of 26 mm.

The bushings are pressed into the reamed holes with an interference fit of 0.015 - 0.02 mm.

Then, the holes in the bushings are drilled and reamed to a diameter of 8-0.012 mm and the holes are countersinked on both sides to a depth of 1 mm at an angle of 90°.

The surface roughness of the holes after processing should be 2.5 microns.

When machining holes, the jig is based on the hole for the roller of the load holder.

Repair of MAZ injection pump regulator

The load of the regulator assembly may have the following defects: loose fit of the bushings 2 (Fig. 4) in the hole of the load 1 of the regulator, wear of the hole in the bushing for the axis of the weights and weakening of the fit of the axle 3 of the load roller or wear of the diameter of the roller axis for the load of the regulator.

Repair of MAZ injection pump regulator

The looseness of the fit of the bushings and the axle is checked by light blows of the copper mandrel. If they are loose, they are changed.

Also, if the holes in the bushings up to a diameter of more than 8.085 mm and the roller axle up to a diameter of less than 6.95 mm are worn out, they are changed.

The bushings 2 are pressed on the press from the inner ends of the lugs with a mandrel (Fig. 5) until they stop at the end.

The roller axis must be pressed in from surface B (see Fig. 3) flush with surface A.

To check the alignment of the surfaces of the holes of the bushings, a control mandrel with a diameter of 8 + 0.008 mm is used, which must pass freely through both holes.

The body of the regulator is made of aluminum alloy AL-10V. Alloy hardness HB 80 - 120.

The main defects that occur during operation are as follows: loosening of the fit of the dowel pins, wear of the hole for the camshaft bearing cage, wear of the holes for the weight holder roller bearing and damage to the threaded holes.

The loosening of the pins is determined by light blows of the copper mandrel.

A new pin is installed with a repair (Increased) size along the seating surface; for this, the hole for the pin is expanded to a diameter of 6.2-0.030 mm to a depth of 10 mm and the pin is pressed in, which should protrude 6 mm above the plane.

The hole for the bearing cage is restored by surfacing, for this the housing is heated to a temperature of 300 - 350 ° C for 15-20 minutes before surfacing, and the surface being deposited is cleaned of the oxide film.

Surfacing is carried out with an OZA-2TuOSZ electrode with a diameter of 4 mm.

After surfacing, the body is heated to a temperature of 300 - 350 ° C for 10 - 15 minutes and then loaded into a dropper, where it is cooled for four hours.

This whole process is performed to ensure high-quality surfacing and relieve internal stresses that occur after welding.

Then, a hole for the bearing race is bored to a diameter of 47 + 0.007 mm for a length of 14 mm and a chamfer of 1x45 ° is bored.

The hole for the bearing of the roller of the load holder is bored to a diameter of 30 + 0.045 mm to a depth of (5 ± 0.1) mm and a chamfer of 0.5x45 ° in the faceplate on a lathe.

If the threads in the holes for the bolts of the regulator cover (M6x1) or for the bolts of the holder roller bearing cup (M8 x 1.25) are damaged for more than two threads, it is repaired by placing brass screws on epoxy glue.

Assembly of the speed controller in are performed in the following order:

insert the key, install the gear bushing on the injection pump camshaft, assemble the gear with crackers and flange, put it on the bushing, check that it rotates easily on the bushing, tighten the gear nut [torque 10 - 20 Nm (1-2 kgcm) and counter.

Play in the damping device is not allowed.

Next, install the shaft with the bearings pressed on it and the weight holder into the glass, lock it with a spring ring, check the ease of rotation of the shaft.

The front bearing must be pressed onto the shaft so that the thickened part of the inner race of the bearing rests against the shoulder of the shaft.

After that, it is necessary to install the cup into the regulator body, securely tighten the cup mounting bolts, carefully lock them with washers, assemble the regulator cover in the reverse order of disassembly, and install the cover on the regulator.

When assembling the regulator cover, please note that:

  • - the regulator lever and the two-arm lever must swing freely on the axis relative to each other;
  • - axial play of the shaft of the spring lever should be 0.1 - 0.3 mm;
  • - to install 27 balls in the groove of the weight coupling, use UM or CIATIM 203 grease or their substitutes;
  • - the screw for adjusting the fuel supply must be turned out flush with the boss of the regulator cover;
  • - when assembling the corrector, the preload of the corrector spring must be ensured within 85 - 95 N (8.5-9.5 kgf).

The adjustment is made using washers installed between the bottom of the corrector body and the spring.

The assembled corrector is installed flush with the support pad of the regulator lever and locked with a nut.

The bearing of the weight coupling should be pressed onto the heel in such a way that the thickened part of the inner race of the bearing rests against the collar of the heel.

In the assembled regulator, all parts must move without jamming, the control lever and the backstage bracket must smoothly return to their original position under the action of the springs.

Repair of MAZ injection pump regulator

The automatic injection advance clutch (Fig. 6) is disassembled on a special tool (Fig. 7).

Repair of MAZ injection pump regulator

First, the driven coupling half 1 is embossed in two places (see Fig. 5), the plug screws 6 are unscrewed from the coupling body and the oil is drained.

During caulking, the need to preserve the bearing sealing end of the driven coupling must be taken into account. To do this, embossing is carried out without bringing the surface of the embossed places to the level of the main end.

During the unscrewing of the coupling half, the caulked sections themselves are flush with the main surface.

Then, the clutch body 11 is unscrewed from the driven half-coupling 1, the drive half-coupling 5 is removed (see Fig. 5) with spacers 16, weights 12, springs 4, gaskets 17 and seals 8 and 10 are pressed out of the clutch body and the drive half-coupling.

Given that the clutch weights, when installed in the assembly, are selected according to the static moment, it is necessary to keep them in pairs during subsequent installation in the injection advance clutch assembly.