On cars with a ZMZ-406 engine, starter 42.3708-10 is installed on the clutch housing on the right side, and with a ZMZ-402 engine - ST230-B4 - on the left side of the clutch housing

Both starters are similar in design and are a DC motor with electromagnetic excitation.

The starter has four poles.

At the top of the starter housing, a traction relay is installed, which has two windings: retracting and holding.

When the key is turned in the ignition switch to position "II", the power supply circuit of the traction relay windings is turned on, while the relay armature is pulled in and through the lever engages the starter gear with the engine flywheel ring gear.

At the end of the stroke, the armature turns on the starter power circuit and at the same time turns off the solenoid coil of the relay (power is supplied only to the holding coil).

When the key is returned to the “I” position in the ignition switch, the power supply circuit of the starter and the holding winding is turned off and, under the action of the spring, the armature disengages the starter gear from the flywheel ring gear.

The ST230-B4 starter device is shown in the figure, and disassembly is shown on the example of starter 42.3708-10.

Removing the starter

1. Disconnect the wire from the "negative" terminal of the battery.

2. Disconnect the wires from the two terminals of the starter traction relay.

3. Unscrew the two nuts of the upper and lower fastenings and remove the starter. On the ZMZ-402 engine, first unscrew the guide tube of the oil level indicator (dipstick)

Starter disassembly

1. Clean the starter from dirt.

2. Loosen two screws 1 and remove the cover 2. Loosen the nut 4 and disconnect the bar 3 from the traction relay terminal.

3. Remove the retaining ring 1. Unscrew the two fastening nuts 2 and remove the cover 3 from the manifold side.

4. Loosen two fastening screws 1 and remove the traction relay 2. In this case, the anchor must remain on the drive lever.

5. Lever out rubber seal 1 on lever with a screwdriver. Remove the anchor 2 of the traction relay, to do this, press the anchor 2 down and disconnect from the lever.

6. Remove stator 1 with brush holder 2. To disconnect the brush holder from the stator, it is necessary to press the ends of the springs 3 and remove two insulated brushes 4 from the holders (these brushes remain on the stator winding terminals).

7. Unscrew the axis of the lever, having previously unscrewed the lock nut on the other side.

8. Remove cover 1 on drive side and remove lever 2.

9. Knock down the retaining ring 1 through the mandrel in the direction of the arrow and remove the retaining ring installed under the retaining ring. Remove the drive 2 starter assembly from the armature shaft.

Checking and inspecting starter parts

1. Clean all starter parts.

2. Check the condition of the stator winding. To do this, turn on the test lamp in an alternating current circuit with a voltage of 220 V and connect it to one of the terminals of the stator winding, the other end of the circuit must be closed to the stator housing.

In this case, the lamp should not light. If the lamp is on, then the insulation is damaged skeins. In this case, replace the winding or stator.

Check the second winding in the same way.

3. Examine the anchor. If the collector is dirty or has marks, scratches, etc., sand the collector with a fine glass sandpaper.

If there is a significant roughness of the collector or protrusion of mica between its plates, grind the collector on a lathe and then grind it with fine glass sandpaper.

The runout of the collector relative to the shaft trunnions should not exceed 0.05 mm. If a yellow coating from the bearing is found on the armature shaft, remove it with fine sandpaper, as this can lead to gear seizing on the shaft.

Check the reliability of the soldering of the armature winding leads to the collector plates.

Inspect the winding at the ends of the armature, the diameter of the winding should be less than the iron package of the armature. Otherwise, replace the anchor.

4. Check the condition of the armature winding using the E-236 device or a test lamp powered by 220 V alternating current.

Voltage is applied to the collector plate and armature core.

The lamp should not be lit. If the lamp is on, then there is a short circuit in the armature winding or collector plate to ground. In this case, replace the anchor.

5. Put the starter drive on the armature shaft, it should move freely, without jamming, along the splines of the armature shaft.

While holding the armature, rotate the starter gear in both directions: clockwise, the gear should rotate freely, and counterclockwise should not rotate. Otherwise, replace the drive.

Traction relay

Check the resistance of the traction relay windings with an ohmmeter.

The resistance of the retracting winding should be in the range of 0.300–0.345 ohms, and the holding winding should be 1.03–1.11 ohms.

The windings can also be checked by connecting a battery to the winding leads. To check the retracting winding, disconnect the terminal from the contact bolt 1 of the traction relay.

Then connect the "-" of the battery to terminal 2 and the "+" to terminal bolt 1 (red diagram). In this case, the relay armature should sharply retract.

To check the holding winding (with the terminal disconnected from the terminal bolt 1), connect the "+" of the battery to terminal 2, and the "-" to the starter housing. In this case, the armature of the traction relay should smoothly retract. Otherwise, replace the traction relay.

The armature of the traction relay must move freely in the housing, without jamming. Inspect the contact bolts.

Scrape the burnt bolt heads with fine sandpaper. In case of severe burnout of the bolt heads, you can turn the bolts by 180 ° so that they are pressed against the contact disk with the unburned side.

If the surface of the contact disc is heavily worn, it can be turned with the non-worn side towards the contact bolts.

7. Check the movement of brushes 1 in holders 2 and 3, the brushes should move easily, without jamming.

Check the fastening of holders 2 and 3 of the brushes, the holders should not dangle.

The holders of the 3 insulated brushes must not have a short to ground (check with a test lamp).

Check the force of the springs 4 pressing the brushes using a dynamometer. To do this, you need to install the brush holder 5 in the cover on the side of the collector, insert the anchor, install the brushes on the collector.

At the moment of separation of the spring from the brush, the force should be in the range of 8.5–14 N (0.85–1.4 kgf). The ends of the springs should press the middle of the brush.

Brushes worn to a height of 5.0 mm must be replaced (brush leads soldered).

8. Inspect the starter covers and replace them if cracks are found.

If the bushings 1 in the covers on which the armature shaft rotates are worn out or they have scuffs, shells, etc., it is necessary to replace the covers with defective bushings.

Starter assembly

1. The starter assembly is carried out in the reverse order of removal.

When assembling, lubricate the bearings (bushings), the spline part and the shaft pins with engine oil.

After assembly, check dimension A, it must be no more than 34 mm.

Turn on the traction relay and measure dimension B between the end of the gear and the thrust ring, it should be within 3–5 mm.

If dimension B does not fall within this limit, then adjust its position by turning the lever axis.

To do this, loosen the locknut, turn the axle and tighten the locknut.

It is recommended that after the final assembly, check the starter at the service station at the mod stand. 532M. The ST230-B4 starter is considered serviceable if, at a voltage of 12 V, it consumes a current of no more than 85 A and develops a speed of at least 4000 min^–1.

Starter 42.3708-10 at 12 V must have the following parameters: 75 A and 5000 min^-1.