Anchor
Check with a megger or with a lamp powered by a voltage of 220 V whether there is a short circuit in the armature winding to the case. Voltage through the lamp is supplied to the collector plates and to the armature core. The burning of the lamp indicates a short circuit of the winding or collector plates with the housing. The megohmmeter during testing should not show a resistance of less than 10 kOhm. The anchor, which has a short circuit with the body, is replaced.
A special device is used to check if there are any short circuits between the armature winding sections or the collector plates, and also if there are any breaks at the place where the leads of the winding sections are soldered to the collector plates.
Inspect the working surface of the collector. If it is dirty or burnt, then clean it with a fine-grained sandpaper with a grain size of 10 - M40. Check the radial runout of the armature relative to the shaft trunnions. If it is more than 0.08 mm - replace the anchor.
Check the condition of the surfaces of the splines and trunnions of the armature shaft. They should not be visible scoring, nicks and wear. If yellow traces from the gear bushing appear on the surface of the shaft, they are removed with a fine-grained sandpaper with a grain size of 10 - M40.
Drive unit
The starter drive elements must move freely, without noticeable jamming, on the armature shaft. The gear must rotate relative to the armature shaft in the direction of armature rotation under the action of a moment of not more than 2.8 kgf-cm. The gear should not turn in the opposite direction. If the drive parts are damaged or significantly worn, replace the drive with a new one.
Stator
They check with a megger or with a lamp powered by a voltage of 220 V whether there are any short circuits in the stator winding to the housing. The voltage through the lamp is supplied to the common terminal of the winding and to the starter housing. If the lamp is on or the megger shows a resistance of less than 10 kOhm, and also if the windings show signs of overheating (insulation blackening), replace the case with windings.
Lids
Check for cracks on lids. If they are, the caps are replaced. Check the condition of the bushings of the rear cover and clutch housing. If they are worn, then replace the rear cover and clutch housing.
Check the reliability of the fastening of the brush holders on the back cover. Brush holders of positive brushes should not have a short circuit with the housing. The brushes must move freely in the grooves of the brush holders. Brushes worn in height up to 12 mm are replaced.
Check the pressure of the springs on the brushes with a dynamometer, which for new brushes should be (1±0,1) kgf. If necessary, replace the springs with new ones.
Traction relay
Check the ease of movement of the relay armature. Then check with an ohmmeter whether the contact bolts of the relay are closed by the contact plate. If the contact bolts do not close, then the relay is disassembled and the contact bolts are cleaned with a fine-grained sandpaper or a flat velvet file. If the contact bolts are damaged at the point of contact with the contact plate, they can be turned by 180°.