Cummins Engine Parts & Complete Diesel Engine Assemblies
Cummins parts and engine assemblies
Find Cummins engine parts or a complete diesel engine by model, application and part number.
Use this page to move between complete construction, marine and generator engines and the replacement components used to repair them. A family name such as 4BT, 6BT, 6CTA, QSM11 or NTA855 is the starting pointโnot final proof of fitment.
For a dependable match, collect the engine serial number (ESN), CPL, complete model suffix, application and the number on the removed component before ordering.
Choose the Right Cummins Catalog Route
โCummins partsโ can mean a complete replacement engine, a major repair assembly or one small service component. Choose the route that matches the job before comparing listings.
Complete Engine Assembly
Use this route for repowers, severely damaged engines and projects that require an assembled power unit rather than individual internal components.
Replacement Engine Parts
Use the component catalog when the repair scope is known: fuel, turbocharger, cylinder, rotating, cooling, starting or overhaul work.
Help Identifying a Part
If the old number is incomplete or the engine has been repowered, send the dataplate and removed-part photos instead of guessing from appearance.
Complete Cummins Diesel Engines by Application
Application changes more than the advertised power rating. Cooling packages, exhaust direction, flywheel housing, oil pan, governor or ECM, starter voltage and accessory drives can differ between a construction machine, generator set and marine installation. Compare the complete engine package, not only the base displacement.
Construction Engines
Engines for excavators, loaders, cranes, pumps and other off-road equipment. Confirm the machine model, rating, mounting and cooling arrangement.
Marine Engines
Propulsion and auxiliary engine listings may use marine cooling, wet exhaust, heat exchangers and application-specific accessories.
Generator Engines
Match rated speed, frequency, governor or control system, SAE housing and generator package requirements.
Automotive Engines
Vehicle applications require the complete model, power rating, electronics, mounting and transmission interface.
Featured Complete Cummins Engine Assemblies
The following 12 current listings represent construction, marine and generator applications across B, C, M, N, K and QSK/QSM families. Availability, condition and included accessories must be confirmed for the exact engine.
Engine condition: complete engines may be supplied as new, remanufactured, rebuilt or used units depending on the individual listing and current availability. Confirm the stated condition, build configuration, included accessories and required freight packaging on the quotation.
Find Cummins Parts by Engine Family
Model-family navigation keeps a 3.9L B-series search separate from a 5.9L B-series, 8.3L C-series or a larger M, N, K or X-series engine. Where a dedicated parts Hub is available, use it before opening the broader catalog.
B Series 3.9L
4B, 4BT, 4BTA and 4BTAA engines used in industrial, construction, marine and generator applications.
B Series 5.9L
6B, 6BT, 6BTA and 6BTAA configurations. Match the application and mechanical fuel-system details as well as the family name.
C Series 8.3L
6C, 6CT, 6CTA and 6CTAA engines. Turbocharging, aftercooling, rating and application change the parts route.
Electronic B and C Families
ISB, QSB, ISC and QSC applications can use electronic injectors, sensors, ECM-related parts and different fuel systems.
L, M and N Series
L10, ISL, QSL, M11, ISM, QSM, NH855, NT855 and N14 cover different mechanical and electronic generations.
K and X Series
KTA19, KTA38, KTA50, QSK, ISX, QSX and X15 parts require the complete engine identity, rating and application.
Shop Cummins Engine Parts by Component
When the repair system is already known, enter the relevant component department and narrow the results with the engine model or old number. Category pages cover multiple engine brands, so confirm that the selected product title or description explicitly includes the correct Cummins application.
Overhaul and Rebuild
Cylinder Components
Rotating Assembly
Camshaft and Internal Parts
Injection Pumps
Injectors and Nozzles
Turbocharger and Air System
Cooling System
Starting System
Engine Search
Complete Engines
Unsure of the Category?
Featured Cummins Parts in the Current Catalog
This selection demonstrates the range across 4BT 3.9L, 6BT 5.9L and 6CT/6CTA 8.3L engines. These products are not a kit and are not interchangeable between the three engine families.
Complete Engine, Overhaul Kit or One Replacement Part?
| Purchase route | When it normally fits the repair | Information required before ordering |
|---|---|---|
| Complete engine assembly | The original engine has major block damage, the repair is not economical, or the equipment needs a replacement power unit. | Full model and rating, ESN/CPL, application, rated speed, flywheel housing, mounting, cooling, controls and required accessories. |
| Overhaul or rebuild kit | The block and major structure remain serviceable, but internal wear requires pistons or liners, rings, bearings and gasket work. | ESN/CPL, piston and liner design, bore, bearing repair size, gasket requirements and measurements after disassembly. |
| Individual replacement part | The failure is limited to a known component such as an injector, pump, turbocharger, thermostat, starter, cylinder head or crankshaft. | Old number, tag or casting, photos, ports, dimensions, voltage, rotation and the engine application. |
How to Identify the Correct Cummins Engine Part
Cummins engine families can remain in service for many years and may be installed in equipment from different manufacturers. Repowers and previous repairs can also separate the installed engine from the machineโs original parts book. Use evidence from the engine and removed component.
Read the dataplate
Record the complete model and ESN exactly as shown.
Record the CPL
The CPL helps narrow the build and rating, but does not replace the part number.
Photograph the old part
Capture tags, stamped numbers, casting numbers, ports and connectors.
Name the application
Provide the machine, generator set, vessel or vehicle model and use.
Compare configuration
Check voltage, rotation, dimensions, mounting and included accessories.
Cummins provides official parts lookup resources through Parts.Cummins.com and QuickServe Online. Use the ESN to review the engine build and current service information, then compare the replacement listing and physical configuration. If the dataplate is difficult to locate or read, follow the Cummins engine serial number lookup guide.
Understand the Product Description Before Ordering
The catalog includes aftermarket replacement parts, complete engine assemblies and other engine components. OEM or Genuine wording should be relied on only when it is explicitly stated and supported in the individual product listing or quotation.
| Term | What it means for the order | What to confirm |
|---|---|---|
| Aftermarket replacement part | A replacement supplied outside the original engine manufacturerโs branded parts channel. | Reference numbers, material or specification information, fitment and warranty stated for that product. |
| OEM/reference number | A number used to identify or cross-reference the component; the number alone does not prove the item in the box is Genuine Cummins. | Brand, manufacturer, condition and which number will be supplied. |
| Complete engine assembly | An assembled engine or engine package. Included accessories vary by listing. | New, remanufactured, rebuilt or used condition; turbo, starter, alternator, cooling, controls, flywheel housing and packaging. |
| Bare, short block or long block | A partial engine assembly with a different level of cylinder-head and accessory completion. | Written scope of supply and every component that must be transferred from the original engine. |
Warranty, Availability and Dispatch
Warranty coverage typically ranges from 3 to 6 months, depending on the product type, condition and applicable supplier terms. Confirm the exact warranty period, start date and exclusions on the quotation or order confirmation.
In-stock items typically dispatch within 1โ3 business days after order and payment confirmation. This is dispatch time, not delivery time. Transit depends on destination, freight method, package size and customs clearance. Complete engines, oversized assemblies and non-stock items require a current availability and freight check.
Information Needed for a Cummins Parts or Engine Quote
- Engine identity: full model, ESN, CPL and readable dataplate photo.
- Part evidence: old part/reference number plus clear photos from multiple angles.
- Application: machine, generator, vessel or vehicle make and model.
- Configuration: rating, rpm, voltage, dimensions, mounting, ports and required accessories where relevant.
- Order details: quantity, destination country and postal code.
- Engine assembly request: required condition, scope of supply and which original accessories will be reused.
Cummins Engine Parts FAQ
How do I find the correct Cummins engine part?
Start with the ESN, CPL and full engine model, then compare the old number and physical configuration. A machine model or the words โCummins 6BTโ are useful clues but may not identify the final component.
Can two engines with the same model use different parts?
Yes. Rating, CPL, application, production change and accessory configuration can affect injectors, pumps, turbochargers, cooling components, starters, gaskets and internal parts.
Do you supply complete Cummins engines as well as spare parts?
The catalog includes complete engine listings and individual replacement components. Engine condition and scope vary, so confirm whether the quoted unit is new, remanufactured, rebuilt or used and which accessories are included.
Can I order using an OEM or replacement number?
A complete number is the best starting point. It must still be checked against the ESN, application and any supersession path. Also confirm whether the listing is aftermarket, OEM-branded or another stated product type.
How quickly can an in-stock item ship?
In-stock items typically dispatch within 1โ3 business days after order and payment confirmation. Delivery time is separate and depends on freight method, destination and customs.
What warranty applies?
Typical warranty coverage is 3โ6 months, but the exact term depends on the item, condition and supplier terms. Use the warranty stated on the quotation or order confirmation for the specific product.
Need a Cummins engine or a matched replacement part?
Send the ESN, CPL, model, old number, application and photos. For a complete engine, also include the required rating, rpm, condition, accessory scope and shipping destination.
