WEST INDUSTRY
1 / 2
4939587 As the engine's "lubrication heart," the oil pump bears the core responsibility of drawing oil from the oil pan, pressurizing it, and delivering it to critical components such as crankshaft bearings, camshafts, and turbochargers. This directly impacts the engine's service life and operational reliability. Featuring a helical gear meshing structure—distinct from traditional spur gear designs—the 4939587 delivers smooth operation, stable oil pressure, and exceptional wear resistance. Tailored for the heavy-duty characteristics of Cummins BS3 5.9L engines, it consistently delivers standard-compliant oil pressure and flow under demanding conditions—including frequent starts/stops, high temperatures, intense vibrations, and high-altitude operations. This prevents critical engine failures like bearing wear and turbocharger damage caused by lubrication failure.
| Part Name | Lubricating Oil Pump | Part Number | 4939587 |
|---|---|---|---|
| Compatible Engine | BS3 5.9 liter B engines | Cross-replacement | 3901175, 3906414, 3914006 |
| Pump Type | Helical gear type, front-mounted gear drive, 23/24-tooth precision meshing design | ||
| Installation | OEM direct-fit design with 1:1 bolt hole alignment. No modifications required. | ||
Manufactured according to original drawings, matching OEM components. No additional debugging is needed after replacement, restoring original lubrication performance instantly.
Precision helical gear structure offers lower resistance and improves oil pressure stability by 30%, preventing instantaneous oil starvation during heavy-duty operations.
High-strength cast iron body with quenching gears (HRC58-62). Designed for a service life matching engine overhaul cycles (approx. 10,000 hours).
| Engines containing spare part 4939587 | |||
|---|---|---|---|
| 4B3.9 / 6B5.9 | B5.9 G / B5.9 GAS | ISB CM550 | ISBE CM800 |
| ISB5.9 CM2150 | ISB5.9 CM2880 | QSB5.9 30 | G5.9 CM558 |
This pump is exclusively compatible with 1989-2002 Cummins BS3 5.9L B Series (6BT) 12V and 24V mechanical direct injection engines. It is incompatible with post-2003 common rail models (e.g., ISB5.9).
Verify three points: 1. Engine model must be Cummins BS3 5.9L B Series; 2. Production Year must be 1989-2002; 3. Fuel System must be Mechanical Direct Injection.
These are cross-interchangeable models with identical core parameters and performance. They are direct replacements for each other requiring no adjustments.
No specialized tools are needed. Regular technicians can complete installation in 2-3 hours by following standard procedures: cleaning surfaces, aligning bolt holes, and tightening to OEM torque.
Ensure the pump body is intact, clean the mounting surfaces, and replace the oil filter and engine oil (API CJ-4 or higher) simultaneously. Pre-lubricate the pump to prevent dry-running at startup.
Common causes include air leaks in the oil circuit, insufficient oil level, or air trapped in the pump housing. Ensure the filter O-ring is seated correctly and idle the engine for 5-10 minutes to purge air.
