Camshaft Catalog for Cummins Marine & Industrial Engines By Model

Introduction

The camshaft is one of the most critical components in any Cummins diesel engine, playing a central role in timing, airflow, and combustion. At Diesel Pro, we specialize in supplying high-quality aftermarket camshafts that match or exceed OEM standards—delivering exceptional durability and performance without the premium price tag. Whether you're working on a marine engine, industrial application, or power generation system, a properly functioning camshaft ensures your engine stays in sync and performs at its peak.

This catalog is designed to help you identify and select the right camshaft for your specific Cummins engine model. You’ll also learn about the function of camshafts, signs of failure, installation considerations, and how Diesel Pro’s camshaft offerings can extend the life of your diesel powertrain.

What Is a Camshaft and Why It Matters

The camshaft is a rotating shaft within the engine that opens and closes the intake and exhaust valves in time with the piston movement. In diesel engines like those produced by Cummins, the camshaft must operate with high precision under extreme pressure and heat conditions.

Primary Functions

• Valve Timing Control: Ensures valves open and close at the right moment for proper combustion and exhaust.
• Injector Actuation: In mechanical diesel engines, cam lobes may actuate injectors directly.
• Synchronization: Works with the crankshaft through timing gears or chains to ensure mechanical harmony.

Even minor imperfections in the camshaft can result in a loss of power, increased fuel consumption, or total engine failure.

Benefits of Choosing Diesel Pro Aftermarket Camshafts

Diesel Pro’s camshafts are engineered to perform reliably under the harsh conditions common in marine, agricultural, industrial, and commercial trucking environments. We supply camshafts that deliver long-term value through strength, efficiency, and a warranty-backed design.

Key Advantages

• Built to OEM Specs or Better: Every camshaft we offer is machined to tight tolerances for optimal performance.
• Hardened Lobes: Designed to resist wear in high-friction applications.
• Backed by Warranty: All camshafts come with a manufacturer’s warranty for peace of mind.
• Fast Shipping Worldwide: In-stock camshafts ship fast, with worldwide delivery available.
• Expert Support: Need help identifying the right part? Our experienced reps can guide you through serial number matching and engine compatibility.

Applications by Cummins Engine Model

We carry aftermarket camshafts for a wide range of Cummins engine models. Below are some of the most common engine platforms supported by Diesel Pro.

Cummins 6B / 6BT / 6BTA (5.9L)

• Applications: Marine propulsion, generators, agricultural tractors, construction equipment, and medium-duty trucks

• Common Signs of Wear: Ticking or knocking sounds, reduced power output, irregular exhaust flow

• Compatibility Note: Camshaft variations exist between naturally aspirated, turbocharged, and aftercooled variants

Cummins 6C / 6CT / 6CTA (8.3L)

• Applications: Tugs, ferries, gensets, school buses, dump trucks, and oilfield equipment

• Failure Risks: Lobe pitting, thrust bearing failure, worn lifters

• Camshaft Tip: Always inspect lifters when replacing the camshaft

Cummins QSB 6.7

• Applications: Marine propulsion, auxiliary engines, agricultural sprayers, and Tier 3 emissions-compliant machinery

• Technology: Uses electronic controls, so camshaft must maintain alignment with sensors and actuators

• Diesel Pro Note: Aftermarket camshafts for QSB engines are designed for tight cam phasing control

Cummins K Series (K19, K38, K50)

• Applications: Large marine engines, oil rigs, mining equipment, and standby generators

• Weight Class: Heavy-duty camshafts designed to handle extreme torque and high RPMs

• Common Upgrades: Replacing stock cams with hardened roller cams to extend overhaul intervals

Cummins N14

• Applications: Heavy trucks, marine propulsion, power generation, and vocational equipment

• Design: Overhead cam configuration; cam and followers should always be replaced together

• Service Tip: Check oil passage clearance and camshaft bushing integrity during installation

Cummins ISX / QSX Series

• Applications: Freight haul trucks, gas compression, mining, marine auxiliary power

• Notable Feature: Dual overhead cam system on early ISX models—high precision required

• Camshaft Concern: Cam lobe scuffing can occur due to low oil pressure or contaminated oil

Common Signs of a Failing Camshaft

Recognizing camshaft issues early can prevent engine failure and costly downtime. The following symptoms may indicate that your camshaft is worn, cracked, or otherwise compromised:

• Tapping or Knocking Noise: Especially at idle or during warm-up.

• Reduced Power Output: A worn cam can disrupt valve timing, impacting torque and horsepower.

• Check Engine Light (Electronic Engines): May show valve timing or injection timing issues.

• Black or Blue Exhaust Smoke: Poor combustion from valve timing errors.

• Metal in Oil Filter: Indicates lobe or bearing surface degradation.

• Uneven Valve Lift: Verified by dial indicator during engine rotation.

Camshaft Inspection and Replacement Tips

Replacing a camshaft is not a casual job. Here are some expert suggestions from Diesel Pro to make the job smoother and more reliable:

Inspection

• Visual Check: Inspect cam lobes for scoring, pitting, or wear spots.

• Micrometer Measurement: Use precision tools to measure lobe lift and compare to specs.

• Thrust Clearance: Verify end play on camshaft to ensure proper seating.

• Journal Surface: Look for discoloration or heat damage.

Replacement Tips

• Replace Lifters Together: Always replace lifters and pushrods with the camshaft to prevent premature wear.

• Use Assembly Lube: Apply camshaft break-in lube liberally to all contact surfaces.

• Proper Torque: Follow correct torque sequence and specifications for camshaft bearings and caps.

• Priming the Oil System: Ensures oil reaches cam journals on first startup.

• Recheck Timing: Ensure the cam-to-crank alignment is exact before sealing the timing cover.

50 Frequently Asked Questions (FAQs)

General Questions

1. What does the camshaft do in a Cummins diesel engine?
   It controls valve timing and may actuate injectors in mechanical systems.

2. Can I reuse the old camshaft when rebuilding my engine?
   Only if it's within spec—always inspect lobes, journals, and end play.

3. Are Diesel Pro camshafts new or reground?
   All camshafts are either new or precision remanufactured to OEM specs.

4. Is it safe to replace the camshaft without replacing lifters?
   No, we strongly recommend replacing both together.

5. Do camshafts come with thrust plates or bushings?
   No, these must be ordered separately unless specified.

6. How do I match the camshaft to my Cummins engine?
   Use your engine model and CPL number or send us your serial number. Contact us if you’re unsure.

7. Do you ship internationally?
   Yes, we offer worldwide shipping with tracking.

8. How can I tell if my camshaft is worn?
   Look for uneven lobes, noise, or metal particles in oil.

9. Is there a warranty on Diesel Pro camshafts?
   Yes, all come with a limited manufacturer’s warranty.

10. What materials are your camshafts made of?
    High-carbon or alloy steel hardened for wear resistance.

Installation & Technical

11. Do I need to reset the valve lash after installing a new camshaft?
    Yes—always recheck lash to factory spec after install.

12. Should I use break-in oil for a new camshaft?
    Yes, it helps protect components during initial wear-in.

13. Can I install the camshaft with the engine in the frame?
    Often yes for inline engines, no for V-configurations.

14. Can timing be adjusted on Cummins mechanical cams?
    Only if adjustable timing gear is installed—most are fixed.

15. What tools are needed for installation?
    Micrometer, dial indicator, torque wrench, cam installation tool.

16. Do I need to press-fit the camshaft?
    No—camshafts should slide into place with oil film if tolerances are correct.

17. What’s the clearance for camshaft end play on Cummins 6B?
    Typically 0.003–0.007". Check your manual for exact spec.

18. Should camshaft bearings be replaced?
    Yes—always replace if the cam is being swapped out.

19. How long does it take to replace a camshaft?
    For inline 6 engines: 6–8 hours. More for larger V-engines.

20. Can Diesel Pro help identify my engine model?
    Yes—contact our team with your serial number or CPL.

Engine-Specific

21. Is the 6BT camshaft different from 6B?
    Yes—turbocharged engines often have different lobe profiles.

22. What’s the lift spec for a 6CTA camshaft?
    Varies slightly by CPL, but ~0.33–0.36” is typical.

23. Do you sell camshafts for KTA engines?
    Yes—we carry camshafts for K19, K38, and K50 engines.

24. Can ISX camshafts be reused?
    Only if not scuffed or worn—dual cams must be measured precisely.

25. Are QSB camshafts the same as 6.7L Dodge Ram?
    No—industrial QSB engines use different sensors and timing.

26. Do N14 camshafts have gear teeth or keyways?
    Most have bolt-on gear drives—check your configuration.

27. Can I replace my camshaft without removing the head?
    Rarely—valvetrain must often be removed to extract the cam.

28. What’s the torque for cam cap bolts on Cummins 6B?
    Usually 18 ft-lbs—check your model’s factory spec.

29. Do you carry marine-rated camshafts?
    Yes, all camshafts are suitable for marine duty with proper maintenance.

30. Do camshafts differ between marine and industrial Cummins engines?
    Yes—differences may include lobe timing and durability coatings.

Troubleshooting

31. My engine is misfiring—could it be a camshaft issue?
    Possibly, especially if accompanied by valve noise.

32. What causes camshaft lobe wear?
    Oil starvation, improper break-in, or using old lifters.

33. Can a bad camshaft cause low oil pressure?
    Not directly, but worn cam bearings can contribute.

34. Why does my camshaft keep failing?
    May be due to contaminated oil or incorrect lifter preload.

35. How do I check camshaft lift?
    Use a dial indicator on the pushrod while rotating the engine.

36. What’s a camshaft core charge?
    A refundable fee for returning a used camshaft—applies to remans.

37. Can camshaft timing affect fuel consumption?
    Yes—incorrect timing reduces efficiency.

38. Do camshaft problems trigger ECU codes?
    Yes on electronic engines—commonly P0016 (cam/crank misalignment).

39. Can I polish worn cam lobes?
    No—replace the camshaft if lobes are visibly worn.

40. Do camshafts wear out with age?
    Yes—especially in high-mileage or poorly maintained engines.

Purchasing & Support

41. How do I know which camshaft to buy?
    Contact us with your engine model, CPL number, or part number.

42. What’s your return policy?
    Returns accepted within 30 days on unused items.

43. Can I get expedited shipping?
    Yes—select options available at checkout.

44. Do you offer wholesale pricing?
    Yes—fleet operators and resellers can contact us for quotes.

45. Is there a core deposit for all camshafts?
    Only on select remanufactured units.

46. Can I order by phone?
    Yes—our team is available to assist with phone orders.

47. Are Diesel Pro camshafts balanced?
    Yes—each unit is inspected for balance before shipping.

48. Do you test camshafts before shipping?
    All undergo visual and dimensional inspection.

49. How can I track my order?
    You’ll receive a tracking number once your item ships.

50. Can I speak with a Cummins parts expert?
    Absolutely—our team includes experienced diesel techs.