Starter vindex drive - 1997 Hyundai Elantra

Assuming the starter motor spins but doesn't engage to turn engine over to start you could have a bad starter drive which is part of the starter assembly or possibly damaged/missing teeth on flywheel ring gear. Depending on year and model vehicle, some starters you can replace just the starter drive otherwise you need to replace the whole starter. If you changed the starter look at the flywheel.

If the starter grinds, it could be the starter drive (bendix) or a bad spot on the flywheel gear.

Might be your battery is not charger to it's fullness, or pump your gas one time it might not be getting enough gas, it's been cold try it.

Your starter drive us weak The drive or sometimes called "Bendix" is spring loaded and mounted in the nose of your starter. 2 options - pull starter, disassemble & install bendix or Just replace starter as an assembly (new starter comes w/new starter drive.)

Make sure to check the flywheel when you remove the starter there may be flywheel damage and that would cause the same problem.

Starter drive (bendix) is bad. Starter drive is spring loaded and when cold sometimes hangs up or spring goes bad. 2 options - remove starter, disassemble and install new starter drive or just buy rebuilt start (has new drive in)

could be a loose wire on the starter , check your connections

The Bendix drive is bad in the starter. You can either rebuild it or just purchase a new rebuilt starter.
The Bendix drive is what pushes the starter gear into the flywheel the then it will turn the flywheel. When the Bendix drive goes bad the starter just spins/whirls.

Shims, are to space the starter drive gear away from the flywheel. The shim is inserted between the engine block, and the starter. The thicker the shim, the more the starter drive gear is further away from the flywheel.

Starter housings are machined from the factory, where they were made. No two housings come out the same, for the machined pad, where the starter bolts to the engine block.
The difference is minimal, granted, but thousandths of an inch count in this area.

It's generally a trial an error situation. This is why there are shim packs. Packs of shims with varying thicknesses.
Rule of Thumb, is generally that the starter drive gear, is 3/32nd's of an inch away from the flywheel.
If you hear a metallic grinding kind of sound, the starter is too close. A thicker shim is needed.

I suspect your problem is the starter drive itself. Definitely sounds like it from your description.
Granted, when bench testing the starter drive kicks out, but the roller clutch inside the Bendix drive is no good. (Starter drive)
Suggest you take the starter back, and get an exchange.

This rebuilt starter has a bad Bendix drive.

Starter solenoid probably.
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Sequence of Operation

NOTE: An overrunning clutch in the drive assembly protects the starter motor (11002) from excessive speeds during the brief period before the driver releases the ignition switch (11572) from the START position (as the engine (6007) starts).

1. The ignition switch is turned to the START position.
   

1. The starter solenoid (11390) is energized, creating a magnetic field in the solenoid coil.
   

1. The iron plunger core is drawn into the solenoid coil.
   

1. A drive lever and pin (11067) connected to the drive assembly engages the starter drive (11350) to the flywheel ring gear.
   

1. When the iron plunger core is all the way into the coil, its contact disc closes the circuit between the battery (10655) and the starter motor terminals.
   

1. The current flows to the starter motor, and the starter drive cranks the flywheel (6375) and the crankshaft (6303).
   

1. As current flows to the starter motor, the pull-in coil is bypassed.
   

1. The hold-in coil keeps the starter drive engaged with the flywheel.
   

1. The starter drive remains engaged until the ignition switch is released from the START position.
   

#1 is the stater with the solenoid on top of it.