Overview of the F30FH-3708100B Starter Motor

The F30FH-3708100B starter motor is a 24V, 4.5 kW unit built for this application. It is a reduction-gear starter with a pre-engaged solenoid, assembled to the original mounting flange and terminal positions so it fits without adapters or wiring changes.

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.

Specifications at a Glance

• Rated voltage: 24V
• Rated output: 4.5 kW
• Pinion: 11 teeth
• Type: reduction gear starter with pre-engaged solenoid
• Net weight: approximately 5 kg
• Condition: new, direct replacement for the original unit

A 24V 4.5 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 drive end housing is cast aluminium and carries the pinion bearing, so the pinion stays square to the ring gear when the motor delivers full torque.

Reference Numbers and Cross References

The following OEM and aftermarket references are listed for this unit:

• 4F110
• F30FH-3708100B
• YC60-8
• 4F115-20
• QDJ2510BT
• F77W3-3708100
• QDJ2510AT

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 7 references in total.

Application Notes

this application applications in this range share the same mounting pattern and terminal layout, which is why one reference can serve several model years. Fitment is still decided by the starter number rather than by the badge on the vehicle. The F30FH-3708100B ships with its solenoid fitted, so no parts have to be transferred from the old unit.

When ordering for a fleet, quote the starter number from each vehicle rather than a single model reference; mixed build dates are common and the starter changed with them.

Why These Starters Fail

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.

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. On this application installations, access to the F30FH-3708100B usually decides how long the job takes.

Fault Symptoms

• No-crank with a fully charged battery
• Cranking that slows noticeably as the engine bay heats up
• Grinding that disappears on a second attempt
• Whine under load, suggesting a slipping pinion clutch
• Starter that continues to spin for a second after the engine fires

Rule out the simple causes first: battery capacity under load, corroded terminals and the signal wire at the solenoid. A starter that clicks with a known-good battery and a clean signal circuit has an internal contact fault. This applies in particular to the F30FH-3708100B supplied for this application.

What to Check Before Fitting

• Battery capacity under load, not just open-circuit voltage
• Terminal clamps and the main cable lug for corrosion or heat marks
• Earth strap between engine and chassis
• Ring gear teeth, visible through the starter aperture
• Key switch and signal wire voltage at the solenoid terminal

Fitting a new starter onto a worn ring gear or a marginal battery shortens its life. Check the simple items first, then fit the unit once and correctly.

Fitting Guidance

Isolate the battery, mark the terminal positions, then disconnect the main cable and the signal wire. Clean around the mounting flange before the starter is withdrawn so dirt does not fall into the bell housing.

Inspect the ring gear teeth and the mounting face, then fit the replacement and torque the bolts evenly. Reconnect the main cable and signal wire, crank the engine for a moment and listen for clean engagement without a screech or grind. The F30FH-3708100B ships with its solenoid fitted, so no parts have to be transferred from the old unit.

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

Hejian Nuojin Auto Parts Co., Ltd. manufactures starter and alternator components for the aftermarket. Every unit is bench tested for no-load current draw, solenoid pull-in and release voltage, pinion throw and running noise before packing.

Standard references are held as spot goods, volume orders are delivered in around 30 days, and every unit carries a one-year warranty against manufacturing defects.

Frequently Asked Questions

Why does the starter work cold but fail when hot?

Heat raises solenoid resistance and reduces brush spring pressure. Both effects build up gradually and appear first on a hot restart.

How do I confirm the starter matches my vehicle?

Read the number on the starter body or on the old unit and compare it with the reference list above. Where the label is missing, match the pinion teeth and the terminal bracket against the photographs.

Can I test the starter on the bench?

Yes. Apply battery voltage to the main stud and the signal terminal and check that the pinion throws and the motor turns. A clamp meter reading against the rated current will show whether the unit is drawing too much.

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.

I. Basic Parameters

II. Specification Parameters (Refer to the same series)

III. Application