12V 10T Starter Motor 4996706 – Cross-Reference for Cummins 4B3.9 6B5.9

Verified Cross-Reference — every listed number checked against engine serial range before dispatch.

Technical Specifications

Application Suitability

When the Right Number Still Refuses to Fit

Cross-reference verification against engine serial is the only reliable path to first-try fitment.

In the Pearl River Delta workshop circuit, I have watched mechanics pull a starter motor off a Cummins QSB5.9 after twenty minutes of struggling, only to discover the spline count matched but the pinion tooth profile belonged to a different CM-series variant. A part number like 4996706 covers a broad family of B-series and QSB-series engines, yet within that family the mounting pattern, terminal orientation, and flywheel engagement depth shift across build codes. Superseded numbers and alternate listings compound the problem — a cross-reference table copied from one supplier to another often carries errors forward silently [NEED_CITE: aftermarket cross-reference accuracy in heavy equipment parts]. That is why every Starter Motor 4996706 for Cummins Engine cross reference fitment inquiry we handle starts with serial-level verification before anything ships.

Engine Serial Range and Build Variant Coverage

This starter motor spans the Cummins B-series and QSB-series families — from the compact 4B3.9 and B3.3 through the mid-range 6B5.9 and G5.9, up to the higher-displacement ISB6.7 and QSB6.7 platforms. Each family carries CM-series build codes (CM550, CM850, CM2150, CM2250, CM2350, CM2850) that determine terminal position and mounting bolt spacing. The Starter Motor 4996706 for Cummins Engine cross reference fitment check must confirm your exact build variant, because a QSB4.5 CM850 and a QSB4.5 CM2250 EC use physically different housings even though the base engine family is the same. Providing the engine serial number or full model designation eliminates the guesswork.

Terminal Orientation, Bolt Pattern, and Pinion Engagement

Three physical interfaces determine whether this unit bolts on and engages correctly: the mounting flange bolt pattern, the electrical terminal orientation relative to the engine block, and the pinion gear throw distance to the flywheel ring gear. The 10-tooth pinion must mesh cleanly with the ring gear — too few teeth and the starter grinds without cranking, wrong throw distance and it fails to disengage after firing. We verify port position and terminal layout against your engine serial before confirming compatibility [NEED_CITE: starter motor flywheel engagement specifications for industrial diesel engines]. If your existing unit has painted-over terminals or a corroded nameplate, a photograph of the mounting face and connector is usually enough to pinpoint the correct variant.

Voltage and Tooth Count Under Real Cranking Loads

The 12V configuration matches the electrical system across all listed Cummins B-series and QSB-series platforms, delivering cranking torque sized for displacement ranges from 3.3 litres to 8.3 litres. The 10-tooth pinion gear is designed for the specific module and pressure angle of Cummins flywheel ring gears in this family — substituting a different tooth count risks partial engagement and accelerated wear on both the pinion and the ring gear. In quarry haul trucks and port-side container handlers where cold-start cycles are frequent, correct tooth geometry directly affects cranking reliability over the unit's service life.

The Cost of Skipping Variant Verification

Ordering by base number alone and discovering a mismatch on site means the machine stays down while the wrong unit ships back and the correct one arrives. In a rental fleet or a contracting operation, that extended downtime cascades — crews idle, project milestones slip, and the emergency freight cost on the replacement often exceeds the price difference between verified and unverified sourcing [NEED_CITE: equipment downtime cost impact in construction and mining operations]. Worse, forcing a near-fit starter onto an engine can damage the flywheel ring gear teeth, turning a simple component swap into a much larger repair.

Why Buyers Route Starter Inquiries Here

Our production lines and qualified sourced supply carry identical QC standards and warranty terms under a single account, so there is no quality gap between self-produced and partner-sourced starter motors. The eight-category catalogue means a repair job needing starter, alternator, seal kits, and filters ships as one consignment rather than split deliveries. We accept orders from a single piece, which suits workshops replacing one failed unit on a downed machine. Guangzhou warehouse stock on fast-failure electrical items allows rapid dispatch for common variants. Part identification works from a part number, machine model, photograph, or nameplate image — whatever the buyer has on hand. Our technical team confirms variant compatibility and cross-references superseded numbers before confirming the order.

Documentation & Verification

• Commercial invoice and packing list referencing engine serial and verified variant code
• Cross-reference sheet mapping 4996706 against 4280007090, 4280007091, 4280007092, 4380003110, 5128000980 (reference only)
• Dimensional inspection on pinion tooth count, bolt pattern spacing, and terminal orientation before dispatch
• Warranty terms covering manufacturing defects for 3–12 months from delivery
• Packing photographs showing protective cradle and terminal cover before crate closure
• HS code and customs classification support for international electrical component shipments

Fitment Check Before Installation

• Compare bolt pattern spacing on the new unit against the removed starter before mounting
• Verify 10T pinion tooth profile against the flywheel ring gear condition visible through the bell housing
• Check terminal orientation matches the engine harness routing — forcing a rotated fit stresses the solenoid post
• Confirm voltage at the starter terminal during first crank to rule out wiring harness resistance issues
• If the unit does not seat flush against the mounting flange, stop and photograph the gap for technical review

Request a Fitment Confirmation

Provide your Cummins engine serial number, full model designation such as QSB6.7 CM2250 EC, or a clear photograph of the existing starter nameplate and mounting face. If the nameplate is unreadable, a photo of the pinion gear alongside the mounting flange is sufficient for identification. Share any cross-reference number printed on the old unit so we can verify superseded or alternate listings against your build.

Frequently Asked Questions

Q: How do I confirm this starter fits my specific Cummins engine variant when only the machine model is known? A: Machine model narrows the field but does not always pinpoint the exact build code. We cross-reference your machine model against known engine serial ranges and CM-series designations to identify the correct variant. In many cases we can confirm compatibility from the machine model alone; when ambiguity remains we ask for the engine serial or a photograph of the existing starter mounting face and connector.

Q: My old part number does not match 4996706 exactly — could it be a superseded or alternate reference? A: Very likely. The cross-reference list includes 4280007090, 4280007091, 4280007092, 4380003110, and 5128000980, all of which refer to the same or closely related starter motor units across different production periods and supplier channels. Share your existing number and we will verify whether it maps to the same fitment for your engine serial.

Q: Why are there multiple part numbers listed for what appears to be the same starter motor? A: Cummins engine platforms have been produced across multiple build generations and manufacturing sources, each assigning its own reference. Superseded numbers replace older listings as designs evolve. Our cross-reference sheet covers these alternate and superseded numbers so buyers can confirm equivalence regardless of which number appears on the original unit.

Q: I only have the engine model, no readable nameplate — can you still identify the correct unit? A: Yes in most cases. Engine model combined with the CM-series build code narrows the correct starter variant significantly. If the build code is also missing, a photograph showing the pinion gear, mounting flange, and terminal layout usually provides enough visual detail for our technical team to confirm the right unit.

Q: Can I order a single sample to verify fitment before placing a fleet order? A: Single-piece orders are standard. Many fleet operators and distributors order one unit for physical fitment verification on a specific machine before committing to a bulk quantity. The sample carries the same warranty terms and inspection standards as a full production batch, so fitment results are representative.