Product Specifications
| Parameter | Details |
|---|
| Part Name | Alternator Pulley |
| Part Number (OEM Reference) | 3926858, 3965146, 3965147 |
| Brand Compatibility | Cummins |
| Engine Fitment | ISB6.7, ISC8.3, QSB6.7, 6B5.9, 6C8.3, B3.3, B4.5, B6.7, G5.9, G8.3, GTA8.3, ISBE4, ISL, ISL9, L9, L9N, QSB3.3, QSC8.3, QSC9, QSL9, QSJ8.9 |
| Condition | New Aftermarket |
| Warranty | 3–12 months against manufacturing defects |
| Packaging | Individual protective packaging with foam insert and branded corrugated box |
Compatible Models
| Brand | Applicable Models |
|---|
| Cummins | ISB6.7 CM2250, ISB6.7 CM2350 B101, ISB6.7 G CM2180 B118, ISC8.3 CM2250, ISC8.3 G CM2180 C101, QSB6.7 CM2250, QSB6.7 CM2250 EC, QSB6.7 CM2250 B128, QSB6.7 CM2350 B105, QSB6.7 CM2350 B112, QSB6.7 CM2350 B130, QSB6.7 M CM2250, QSB6.7 CM850(CM2850), 6B5.9, 6C8.3, B3.3, B4.5, B6.7 CM2350 B121B, B6.7 CM2350 B136C, B6.7 CM2350 B157C, B6.7 CM2450 B155B, B6.7N CM2380 B150B, B6.7O CM3580 B193B, C GAS PLUS CM556, G8.3 CM558, GTA8.3 CM558, ISBE4 CM850, ISL CM2150, ISL CM554, ISL CM850, ISL9 CM2150 SN, ISL9 CM2250, ISL9 CM2350 L101, ISL9 CM2350 L111, L GAS PLUS CM556, L8.9 L121, L9 CM2350 L116B, L9 CM2350 L119B, L9 CM2350 L120C, L9 CM2350 L129C, L9 CM2350 L133C, L9 CM2450 L126B, L9 CM2450 L143C, L9N CM2380 L124B, L9N CM2380 L130B, N14 MECHANICAL, QSC8.3 CM554, QSC8.3 CM850(CM2850), QSC9 CM2250/QSL9 CM2250, QSL9 CM2250, QSL9 CM2250 L115, QSL9 CM2350 L102, QSL9 CM2350 L107, QSL9 CM2350 L118, QSL9 CM554, QSL9 CM850(CM2850), QSL9 G CM558, QSL9 M CM2250 L106, QSJ8.9 G |
Tired of Alternator Pulley Failures on Your Cummins ISB6.7 or QSB6.7 Engine?
Every unplanned engine shutdown due to pulley slippage or bearing seizure costs fleet operators thousands in lost uptime and labor. OEM 3926858 pulleys often require 3-week lead times — delaying critical maintenance. Counterfeit alternator pulleys fail within weeks under high-torque conditions, causing voltage instability and battery charging issues that cascade into full electrical system failures.
OEM-Equivalent Quality, Ready to Ship from Guangzhou Warehouse
This Cummins alternator pulley (3926858) is manufactured in ISO-certified factories and rigorously tested before shipment to match OEM performance standards. With 10 years’ experience supplying heavy equipment parts globally, XUNPO maintains over 10,000 SKUs in stock — including this direct-fit replacement for ISB6.7, ISC8.3, and QSB6.7 engines used in construction excavators, generator sets, and off-road trucks. We verify fitment before quoting, ensuring no guesswork during engine rebuilds or field repairs.
Where This Part Works
This 3926858 pulley operates reliably across demanding environments: quarry haul trucks subject to continuous vibration, marine auxiliary power units exposed to salt air, port container handlers running 24/7, and demolition excavators with frequent high-load cycles. In these applications, precise belt alignment and thermal stability are critical — a misaligned or low-hardness pulley accelerates alternator bearing wear and reduces output efficiency by up to 18% under load.
Engineering Details That Matter
Forged 45# carbon steel ensures consistent grain structure and fatigue resistance at operating temperatures up to 120°C. Surface hardness is precisely controlled at HRC 42–46 after quenching and tempering — balancing wear resistance with impact toughness. Dimensional tolerances are held to ±0.05 mm on bore diameter and runout ≤0.08 mm — guaranteeing concentricity and eliminating belt flutter. The precision-ground V-groove profile matches OEM belt contact angle (34°) to prevent premature rib cracking. Zinc-nickel plating provides 500+ hours salt-spray corrosion resistance per ASTM B117, essential for coastal and mining operations.
The Real Cost of Wrong Parts
A $25 counterfeit pulley may save upfront but risks $2,400+ in downtime for a single day’s missed job schedule — not counting labor to re-install the alternator, replace damaged belts, or diagnose downstream voltage faults. OEM-spec replacements like this 3926858 pulley meet SAE J1930 and Cummins Engineering Standard CES-11402 for torque transmission and thermal cycling. Choosing based on total cost of ownership (TCO), not unit price, means fewer repeat failures, longer alternator life, and predictable maintenance intervals — verified by ISO 9001 production controls and pre-shipment functional testing.
Why Customers Trust XUNPO
We partner exclusively with ISO 9001-certified factories and conduct incoming material inspection on every batch. Every 3926858 alternator pulley undergoes 100% performance testing — including dynamic balance, torque transfer verification, and temperature-cycled endurance checks. All parts carry a 3–12 month warranty covering manufacturing defects. With 10 years of export experience serving clients in 120+ countries, our 20+ technical specialists confirm part compatibility within 2 hours. Over 10,000 commonly used parts — including this Cummins ISB6.7 alternator pulley — are held in ready-to-ship stock at our Guangzhou warehouse.
Packaging & Shipping
- Individually packed in anti-static polybag with molded EPE foam and reinforced export carton
- In-stock items shipped within 2–5 working days after payment confirmation
- Flexible logistics: DHL/FedEx/UPS express, air freight, or sea freight options available
- Real-time tracking number provided upon dispatch
- MOQ: 1 piece — supports urgent field repairs and small-fleet operators
Get Your 3926858 Alternator Pulley Now
Your engine can’t wait — every hour of delay adds cost. Send us your machine model, quantity, and destination, and receive a competitive quote within 24 hours. First-time buyers may request a sample for functional testing before bulk order. With Guangzhou warehouse stock and global logistics partners, your replacement arrives fast — so your equipment stays online.
Frequently Asked Questions
Q: Is this an original Cummins part or an aftermarket replacement?
A: This is an OEM-equivalent aftermarket alternator pulley, produced in ISO 9001-certified factories and tested to meet Cummins engineering specifications for fit, form, and function.
Q: How do I confirm if this 3926858 pulley fits my specific engine?
A: Provide your exact engine model (e.g., QSB6.7 CM2350 B130), serial prefix, and application — our technical team verifies compatibility and responds within 2 hours.
Q: What is the warranty period for this alternator pulley?
A: We offer a 3–12 month warranty covering defects in materials and workmanship. Claims are processed with no questions asked for confirmed manufacturing faults.
Q: What is the minimum order quantity?
A: MOQ is 1 piece — designed for urgent maintenance needs and small-volume buyers.
Q: How long does shipping take after order confirmation?
A: In-stock items ship within 2–5 working days. Express courier delivery typically reaches North America/Europe in 4–7 days; air freight and sea freight timelines vary by destination.
Q: Can I request a sample before placing a bulk order?
A: Yes — first-time customers may request a sample for physical verification and functional testing prior to full order placement.
Ready to order or need a quote?
Send your part number, machine model, and quantity — we'll respond within 24 hours.
WhatsApp: +86 187 2205 7128 | Email: talos@xunpojx.com
