Starter solenoid: replacement and selection

When and why it is necessary to replace starter solenoid

Manufacturers do not specify exact lifetime of the starter solenoid. Replacement of the part is performed in case of thermal damage of the contact plates or power contacts, burning-out or tearing of the winding, breakdown of drive elements (mechanical damages of the armature, jamming or loosening of the spring), damaging of the magnet due to casing integrity violation, oxidation of the rod.

Wear-out of the drive elements is caused by frequent use and improper usage of the starter. The contacts and winding are often damaged as a result of short circuit due to ingress of moisture or voltage variations in the car electric circuit. A road accident can become the cause for magnet damaging. And the component rod gets oxidized because of ingress of condensed moisture at temperature variations.

The main sign of solenoid starter switch defect is unstable operation of the starter, during which the engine is not starting, but clicks of starter solenoid at ignition key turning are heard. This is a symptom of thermal damaging of the contact plates. Jamming of drive elements or winding breakage can be indicated by the solenoid non-actuation (absence of specific click at ignition turning on).