24V 4KW 10T Starter Motor STB4307RB for Iveco

Overview of the STB4307RB Starter Motor

Iveco owners replacing a tired starter will find the STB4307RB a direct fit: a 24V, 4 kW reduction-gear unit with a pre-engaged solenoid, produced to the original flange and terminal layout.

Cranking load varies with temperature, battery condition and engine condition. A healthy starter has margin for all three; a worn one turns the engine just slowly enough that the control unit hesitates and the driver notices long, laboured starts.

Technical Summary

• Rated voltage: 24V
• Rated output: 4 kW
• Pinion: 10 teeth
• Type: reduction gear starter with pre-engaged solenoid
• Application: Iveco
• Net weight: approximately 7.7 kg
• Condition: new, direct replacement for the original unit

A 24V 4 kW rating is the output the motor can hold while cranking, not a peak figure. It is sized so the engine reaches starting speed on the first or second revolution, which is what makes a healthy start feel immediate.

The reduction gearset lets the motor run at high speed while the pinion turns slowly with high torque, which is why the unit stays compact enough for a crowded engine bay.

Reference Numbers and Cross References

Cross references for this starter are listed below. They are a matching aid rather than a substitute for checking the number on the old unit:

• 0001231039
• S0429
• 0001251003
• 0001251004
• STB4307RB
• 0001263023
• STB4307WA
• 0001263024
• 861314
• 438331
• 114307
• 116473
• DRS0153
• 8EA012586631
• MS139
• 11131501

Starter suppliers revised this design more than once during production. Confirm the number on the old unit, or send a photograph of the drive end, before committing to an order. This starter is listed with 16 references in total.

Application Notes

This starter family was fitted to a range of Iveco applications, and the part number changed as engines and flywheels were revised. The unit listed here covers the references above and is a direct replacement where those numbers match. Where a STB4307RB has been replaced before, check that the fitted unit still matches the reference list.

A mismatched pinion is the most common cause of a starter that engages noisily or refuses to mesh. Compare the tooth count before fitting, not after.

What Wears Out First

Oil or coolant mist from a leaking seal finds its way into the drive end housing, mixes with carbon dust and forms a conductive paste. The starter then arcs internally and fails early, whatever its mileage.

The brush plate is the second common failure point. Brushes shorten gradually, spring pressure falls, and contact becomes intermittent. Cranking speed drops a little every week until the engine refuses to start on a cold morning. The STB4307RB ships with its solenoid fitted, so no parts have to be transferred from the old unit.

What to Look For

• Click from the solenoid with no rotation, sometimes clearing on a second attempt
• Cranking that has become slower over several weeks
• Grinding as the pinion meets the ring gear
• Starter that keeps running after the key is released
• Intermittent no-crank that appears when the engine bay is hot

A cranking voltage test separates the starter from the rest of the circuit. If battery voltage stays healthy at the terminals but drops sharply at the starter stud, the cable or the connection is at fault rather than the motor. The STB4307RB is built to the same flange pattern as the unit it replaces.

Checks Before Installation

• Condition of the old pinion and ring gear before the new unit goes in
• Main cable continuity and the condition of the lug at the starter stud
• Battery voltage while cranking, measured at the battery posts
• Mounting face cleanliness and bolt condition
• That the replacement terminal layout matches the original harness

Most comebacks after a starter replacement trace back to something that was not checked before the unit went on: a tired battery, a corroded earth or a chipped ring gear. Ten minutes with a multimeter and a torch prevents the second repair.

Installation Procedure

Disconnect the battery negative terminal, remove the intake parts that restrict access, then disconnect the main cable and the solenoid signal connector. Support the starter before removing the mounting bolts.

After fitting, confirm the pinion returns freely and the cables are clear of the exhaust. Crank once before the first drive, then re-check the main terminal for tightness after the first heat cycle. For the STB4307RB, the practical check is the number stamped on the housing.

Quality Control and Supply from Hejian Nuojin Auto Parts Co., Ltd.

Each production batch is inspected for housing dimensions, terminal integrity and pinion fit, and every starter is bench tested before it is boxed. Units ship in neutral cartons with foam protection, which keeps freight damage low and allows distributors to label stock under their own brand.

Common references are kept in stock for fast dispatch, volume orders are delivered in around 30 days and each starter carries a one-year warranty against manufacturing defects.

Frequently Asked Questions

Does the starter need any maintenance?

No routine maintenance is required. Keeping the battery, terminals and earth connections clean is what extends starter life in practice.

Why does the starter click but not turn?

A click with no rotation usually means the solenoid pulls in but the contact does not pass current. Check the earth strap and the main cable before condemning the starter.

Does this starter come with the solenoid?

The starter is supplied as a complete assembly including the solenoid. Reuse the original mounting bolts if they are in good condition.

How long should a replacement starter last?

Service life depends on starting frequency, battery condition and heat exposure. On a daily-driven vehicle with clean connections, ten years or more is realistic.