Cummins 6BT5.9-G1 86KW 115HP Generator Engine
6-cylinder in-line diesel engine for prime and standby generator sets, supplied as the Cummins 6BT5.9-G1 at 86 kW (115 HP) at 1500 rpm from 5.9L.
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What This Engine Is Built For
MEP Power supplies the Cummins 6BT5.9-G1 as a complete 6-cylinder in-line generator drive diesel engine of 5.9L running a 102 * 120 mm bore and stroke. It is rated at 86 kW (115 HP) at 1500 rpm. The engine is turbocharged and water cooled, with a Weifu A Pump/RSV Governor fuel system. Typical duty is prime and standby generator sets; dry weight with flywheel and alternator is 411 Kg and the overall envelope is 1110mm*750mm*988mm 6BT5.9-G1.
Key Benefits
- Delivers 86 kW (115 HP) at 1500 rpm from 5.9L as a factory-rated assembly.
- Turbocharged induction with water cooling keeps charge temperature under control in continuous duty.
- Dry weight 411 Kg and envelope 1110mm*750mm*988mm 6BT5.9-G1 are published so the installation can be checked before ordering.
- Starts without auxiliary aids down to -12℃.
- Genuine and OEM options quoted side by side so the budget decides, not the catalogue
- Built on the 6BT5.9 platform, a Cummins family with parts availability worldwide
Application Scenarios
- Prime mover for a new generator set build
- Standby set engine replacement
- Rental power fleet rebuild
- Containerised power module
Who It Is For
- Genset packagers matching an engine to an alternator
- Rental power companies rebuilding sets between contracts
- Industrial sites replacing the prime mover in an existing canopy
- Telecom and data infrastructure contractors specifying standby power
Problems It Solves
- An engine that does not hold speed under block load makes the whole set unusable.
- Packagers lose weeks when the engine does not match the alternator and the base frame.
- Standby sets sit idle for months and must still start and take load on demand.
- Identifying the right 6BT5.9-G1 variant from a serial number takes experience; MEP Power checks the configuration before quoting.
Specification As Published
Values below are the published data for this unit. Where a figure is not listed it was not stated by the source data sheet; ask and we will confirm before you order.
| Model | 6BT5.9-G1 (86kw) |
| Type | 6 Cylinders in Line, 4 Stroke Diesel |
| Displacement | 5.9L |
| Bore x Stroke | 102 * 120 |
| Net Weight | 411 Kg |
| Overall Dimension | 1110mm*750mm*988mm 6BT5.9-G1 |
| Standby Power | 548/586 N.m @ 1500 rpm |
| Rated Power/Speed at 1800 rpm | 100 kW/133HP @ 1800 rpm Standby Power (1800 rpm): 110 kW/147HP @ 1800 rpm |
| Low Idle Speed | 950-1050 rpm Fuel Consumption @ Running: ≤ 248g/Kw.h 6BT5.9-G1 |
| Aspiration | Turbocharged |
| Fuel System | Weifu A Pump/RSV Governor |
| Governor Type | Mechanical, Regulation ≤5% |
| Electrical System (starter motor/alternator) | 12V/24V |
| Lowest Starting Temp (without auxiliary system) | -12℃ |
| Engine Cooling Fluid Volume | 9.9 L |
| Cooling Method | Water Cooled |
| Rated Power | 86 kW (115HP) |
| Rated Speed | 1500 rpm |
| Cylinders | 6 Cylinders in-line |
| Prime Power | 86 kW (115HP) |
Technical Features
- Cylinders: 6 Cylinders in Line, 4 Stroke Diesel
- Displacement: 5.9L
- Bore and stroke: 102 * 120
- Aspiration: Turbocharged
- Fuel system: Weifu A Pump/RSV Governor
- Governor: Mechanical, Regulation ≤5%
- Electrical system: 12V/24V
- Coolant capacity: 9.9 L
Quality Control
- Every engine is inspected by the MEP Power inspection team before it leaves the warehouse
- Engine, configuration and serial numbers are recorded and photographed for the buyer
- Genuine and OEM units are quoted separately so the buyer knows exactly what is supplied
- Warranty on genuine and OEM new engines and generator sets is one year or 1000 hours, whichever comes first; parts and repair labour are covered for quality faults inside that period.
Use and Installation Guide
- Quote the model 6BT5.9-G1 when ordering so the correct variant is supplied.
- Match the flywheel and SAE housing to the alternator before assembly
- Set the governor to the frequency required, 50 Hz or 60 Hz
- Run a load bank test before the set goes into service
- Keep the warranty terms in mind: one year or 1000 hours, whichever comes first.
Customisation Options
- OEM and ODM builds, including your logo and company name on the unit
- Cummins engine customisation and modification to your requirement
- Mining and special explosion-proof builds
- Genuine or OEM parts specified on the quotation
How It Compares
| Compared with | What to consider |
|---|---|
| A rebuilt or used engine of the same rating | A rebuilt unit may show the same 86 kW (115 HP) on paper, but its running history is unknown and the warranty rarely covers the whole engine. |
| A larger engine in the same 6BT5.9 range | Moving up a frame size adds weight, envelope and fuel burn; specify the next size up only if the duty cycle really needs the headroom. |
| A non-Cummins engine of similar output | Parts and service for Cummins families are available in most markets, which matters more over ten years than the purchase price on day one. |
6BT5.9-G1 Questions
Is this 6BT5.9-G1 a genuine Cummins engine
What power does the 6BT5.9-G1 produce
What warranty comes with the engine
How do I confirm this is the right variant for my machine
How is the engine shipped and what payment terms apply
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Quote The 6BT5.9-G1
Send your serial number or nameplate photograph and we will confirm the configuration, then price genuine and OEM options side by side.



