How can I connect my starting motor

If your 1989 Buick Century’s starter motor spins but the Bendix gear (the part that engages the flywheel) doesn’t pop out, you're likely facing one or more of the following issues—especially since the starter cables were disconnected when you got the car.

Let’s go step by step:

Your starter motor has two or three terminals:

1. B (Battery terminal) — large stud for thick cable directly from the battery (+)
2. S (Solenoid signal terminal) — smaller terminal, gets 12V from the ignition switch when you turn the key
3. (Sometimes) R terminal — not always used; originally sent power to the coil during cranking on older systems

Correct wiring:

• Thick battery cable (positive) from the battery goes to the B terminal (large post).
• A smaller wire (usually purple) goes from the ignition switch to the S terminal.
• The starter must be grounded through its mounting bolts to the engine block.

📌 Make sure the ground strap from engine to chassis is intact!

If your wiring is correct and:

• You hear the starter spinning, but it doesn’t crank the engine → the Bendix gear isn't engaging the flywheel.

1. Low battery voltage
   • 🔋 Starter might spin but solenoid doesn't have enough juice to push the Bendix out.
   • ✅ Try jump-starting it or use a multimeter: make sure battery is at 12.6V+.
2. Weak or broken solenoid
   • Solenoid is the part that pushes the Bendix gear out.
   • If it clicks or buzzes but doesn't move the gear → it's likely bad or sticky.
   • 🔧 Try tapping the starter lightly with a hammer while someone turns the key.
3. Incorrect wiring
   • If the small wire is on the wrong terminal, the solenoid might never get signal.
   • ✅ Double-check the small wire goes to S terminal.
4. Bad starter (even if new or rebuilt)
   • If it was sitting for a while or is used, the Bendix can get jammed.
   • May need disassembly and cleaning or complete replacement.

• Turn ignition key to ON (not START).
• Use a screwdriver or remote starter to short the large post (battery) to the S terminal on the starter.
  • If the Bendix kicks out and turns engine = ignition circuit may be at fault.
  • If it still doesn’t engage the flywheel = starter itself is likely bad.

Component Check Battery voltage 12.6V+ at rest Starter wiring Big cable to large post, purple wire to S terminal Engine ground strap Tight, clean contact Starter mounting Bolted firmly to engine Solenoid action Clicking and pushing Bendix gear forward Flywheel Not damaged or missing teeth (remove starter to see)