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Replace Starter Motor and Solenoid

The starter motor on your car's engine is designed to crank the engine over fast enough to allow the normal engine internal combustion process to take over. Most starters are operated by using a high current 12 volt battery with large gauge positive battery cable connecting the starter to the battery and engine ground to complete the circuit. The ignition switch is used to supply a trigger voltage signal to the starter solenoid. The solenoid in turn controls the high amperage voltage used to operated the starter motor. On the nose of the starter motor is a bendix gear which is thrown out into the flywheel or flex plate when the starter has been activated. 

Once the engine starts the bendix gear is forced back into the starter motor. The starter motor has built in safety devices to not allow the starter to operate if the cars transmission is left in gear. These safety devices are called a neutral safety switch and a clutch safety switch depending on the transmission type of the vehicle. When a starter fails it can do so in a variety of ways such as a rapid clicking noise, one click when the ignition key is turned to the crank position, slow cranking and grinding noise when the starter bendix gear contacts the flywheel. The car battery must be in good working order with a proper state of charge in order for the starter to work properly. Low battery voltage can cause the starter to create a rapid clicking noise often described as a "machine gun" sound. 

If you suspect the battery could be your problem visit: How to check a car battery. Battery cables can cause starter problems as well, inspect the cables and look for corrosion, overheated connections and melted or bulged insulation. These are all signs the battery cable could be failing under load.

Before we start, place your car on level ground with the emergency brake on and the engine in cool condition. Also, wear protective clothing, gloves, and eyewear.
 


Tools and Supplies Needed to Complete This Job

1. Set of sockets and socket wrench with extensions

2. Phillips and standard screw drivers

3. Pliers

4. Wrench set

5. Replacement starter
 


Replacement Directions

Step 1 - Start with engine cold

Step 2 - Remove the negative battery cable at the battery

Step 3 - Remove all electrical wires that lead to the wiring harness and main battery cable connections. (note: sometimes this step is easier after the starter motor has been removed)

Step 4 - Remove all accessories (if any) to access starter motor mounting bolts, next remove starter motor mounting bolts, remove the starter.

Step 5 - Clean starter mounting surfaces thoroughly


Step 6 - Install new starter and tighten evenly

Step 7 - Reconnect wiring and cable

Step 8 - Reconnect the negative battery cable (note: if major spark are present when the battery is re-connected the starter battery connection needs to be inspected)

Step 9 - Recheck starter operation (note: if the starter motor operation is excessively noisy the starter motor may need to be repositioned using shims)
 

Best Practices

  • Always check all battery cables and terminals condition, look for overheating and corrosion. A starter's life can be cut short if bad connections exist.
  • Use factory replacement parts for best results and longest starter operation.

If further assistance is needed, our certified car repair technicians are ready to answer your car questions. Also, gain manufacturer specific instructions and information by clicking - Auto Repair Manual

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