Home | Blog

Cummins C Series Engine Comprehensive FAQ

February 10, 2025

 

General Information for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What is the Cummins C Series engine used for?

Question: What are the common models in the Cummins C Series?

Question: What is the displacement of the Cummins C Series engine?

Question: What is the firing order for the Cummins C Series?

Question: What type of fuel does the Cummins C Series use?

Maintenance and Service for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: How often should the oil be changed?

 

Question: What type of oil should be used?

 

Question: What is the oil capacity?

Question: What is the valve clearance specification?

 

Question: How often should valve adjustments be made?

Troubleshooting for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: Why is my Cummins C Series engine overheating?

Question: What causes white smoke from the exhaust?

Question: Why is my engine hard to start in cold weather?

 

Question: What does low oil pressure indicate?

Question: What should I do if the engine won't start?

Specifications and Technical Data For Cummins C Series Engines (6C, 6CT. 6CTA)(1991 and 1994 Certification Levels)

 

Question: What is the compression ratio of the Cummins C Series?

Question: What is the normal operating oil pressure?

Question: What is the maximum allowable coolant temperature?

Question: What is the recommended battery size?

Question: What is the maximum turbocharger boost pressure?

Fuel System For Cummins C Series Engines (6C, 6CT. 6CTA)(1991 and 1994 Certification Levels)

Question: What type of fuel filter does the Cummins C Series use?

Question: How often should fuel filters be replaced?

Question: What is the fuel injection pressure?

Question: What is the fuel consumption rate?

Question: What causes fuel contamination issues?

Cooling System For Cummins C Series Engines (6C, 6CT. 6CTA)(1991 and 1994 Certification Levels)

Question: How do I bleed air from the cooling system?

Question: What is the coolant capacity?

Question: What coolant should be used?

Question: What causes coolant loss without visible leaks?

Question: How often should coolant be changed?

Lubrication System for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What is the oil filter part number for the C Series?

Question: How do I check the oil level?

Question: What causes oil dilution in diesel engines?

Question: How do I reset the oil change indicator?

Question: Can synthetic oil be used?

Electrical System for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What voltage does the Cummins C Series operate on?

 

Question: What size alternator is recommended?

Question: How do I troubleshoot charging system issues?

Question: What causes battery drain when the engine is off?

Question: How do I test the starter motor?

Exhaust and Emissions for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What is the EGR system?

Question: How do I know if my turbocharger is failing?

Question: What causes black smoke from the exhaust?

Question: How do I check for exhaust leaks?

Engine Testing and Diagnostics for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: How do I perform a compression test?

Question: What is the normal compression pressure?

Question: How do I check timing on the C Series?

Question: What are signs of a blown head gasket?

Question: How do I diagnose poor engine performance?

Engine Assembly and Components for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What material is the Cummins C Series engine block made of?

Question: How many cylinders does the Cummins C Series have?

Question: What is the bore and stroke of the Cummins C Series engine?

Question: What is the purpose of the camshaft in the C Series engine?

Question: How is the camshaft driven in the C Series?

Turbocharger System for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: Does the Cummins C Series have a turbocharger?

Question: What are signs of turbocharger failure?

Question: How do I maintain the turbocharger?

Question: What causes turbo lag?

Question: Can I upgrade the turbo on my Cummins C Series?

Cooling System (Advanced) for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What causes overheating despite having enough coolant?

Question: What is cavitation in the cooling system?

Question: How do I prevent cavitation?

Question: How do I test the thermostat?

Question: Why is there oil in my coolant?

Fuel System (Advanced) for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: How do I bleed air from the fuel system?

Question: What are the symptoms of a clogged fuel filter?

Question: How do I know if my fuel injectors are bad?

Question: What causes injector failure?

Question: Can I clean diesel fuel injectors?

Electrical System (Advanced) for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: Why is my alternator not charging the battery?

Question: What is a parasitic draw?

Question: How do I test for parasitic draw?

Question: Why does my starter click but not turn the engine?

Question: How do I check for a bad ground connection?

Exhaust System (Advanced) for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What causes excessive exhaust backpressure?

Question: How do I measure exhaust backpressure?

Question: What are the dangers of excessive exhaust backpressure?

Question: What causes a noisy exhaust?

Crankshaft and Bearings for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What causes crankshaft wear?

Question: How do I check for crankshaft end play?

Question: What is the purpose of main bearings?

Question: What causes bearing failure?

Question: How do I identify a spun bearing?

Cylinder Head and Valves for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What are signs of a cracked cylinder head?

Question: How do I check valve seat wear?

Question: What is valve float?

Question: What causes bent valves?

Question: How do I adjust valve lash?

Gaskets and Seals for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: What causes head gasket failure?

Question: How do I detect a blown head gasket?

Question: What is the purpose of O-rings in diesel engines?

Question: How do I prevent gasket leaks?

Question: Why do seals fail prematurely?

Engine Overhaul and Rebuild for Cummins C Series Engines (6C, 6CT, 6CTA) (1991 and 1994 Certification Levels)

Question: When is an engine rebuild necessary?

Question: What parts are typically replaced during an overhaul?

Question: How long does an engine overhaul take?

Question: What causes premature engine wear?

Question: How do I break in a rebuilt engine?

Read More

Best Practices for Long-Term Engine Health For Cummins 6C, 6CT, 6CTA (1991 and 1994 Certification Levels)

February 10, 2025

 

Introduction

Maintenance Schedules and Procedures

Daily Maintenance Checks

Every 250 Hours (or Monthly)

Every 500 Hours (or Every 3-6 Months)

Every 1,000 Hours (or Annually)

Every 2,000 Hours (or Every 2-3 Years)

 

The Value of Using Premium Aftermarket Parts

Why Choose High-Quality Aftermarket Parts?

Recommended Aftermarket Parts for Cummins C Series

Proactive Maintenance to Prevent Costly Repairs

Common Preventable Issues

The Financial Impact of Preventative Maintenance

Final Thoughts

Read More

Why It Often Makes Sense to Overhaul Instead of Re-Power Your Marine Diesel Engine

February 5, 2025

Key Takeaways

1) Faster Turnaround and Less Downtime

Overhaul Kit Catalog  For Cummins Marine Engines

2) Cost-Effectiveness of an Overhaul

Overhaul Kit Catalog For Detroit Diesel Marine Engines

3) Understanding the True Condition of Your Engine

Overhaul Kit Catalog For Caterpillar Marine Diesel Engines

4) Compatibility with Your Existing Setup

5) Environmental and Regulatory Considerations

6) Maintaining Engine Familiarity and Reliability

7) When Re-Powering Might Be the Better Option

Final Thoughts

Read More

Why Buying a New Cylinder Head for Your Caterpillar Is Sometimes Better Than Sending It to the Machine Shop

February 4, 2025

Key Takeaways

1. The Hidden Costs of Machining

Key Hidden Costs of Machining:

Labor Costs

Additional Repairs

Downtime Costs

Multiple Shop Visits

Material Costs

Shipping and Handling

Precision Risks

Long-Term Uncertainty

2. Time Is Money: Minimizing Downtime

Key Factors Contributing to Downtime

Loss of Business Operations

Logistics and Shipping Delays

Risk of Incomplete Repairs

Increased Labor Costs for Idle Workers

Higher Rental Costs for Temporary Replacement Equipment

Customer Dissatisfaction Due to Service Delays

3. Reliability & Performance of a New Cylinder Head

Key Factors Affecting Reliability & Performance:

Structural Integrity

Improved Engineering

Factory-Tuned Components

Consistent Compression and Sealing

Reduced Risk of Overheating and Warping

Elimination of Past Wear and Fatigue

Long-Term Cost Savings and Durability

4. Warranty Protection and Long-Term Value

Key Benefits of a Warranty-Backed New Cylinder Head:

Manufacturer's Warranty

Better Resale Value

Lower Risk of Rework

Protection Against Defects and Failures

Increased Engine Reliability

Cost Savings on Future Repairs

5. Compatibility and Perfect Integration

Key Benefits of a New Cylinder Head for Integration

Matches OEM Specifications

Avoids Machining-Related Misalignment Issues

Reduces Installation Time and Complexity

6. Fuel Efficiency and Emissions Compliance

Key Issues Caused by a Worn-Out Cylinder Head:

Increased Fuel Consumption:

Higher Emissions

Loss of Power

Poor Air-Fuel Mixture Control

Overheating Risks

Inefficient Combustion Cycles

7. When a Machine Shop Is a Viable Option

Situations Where Re-Machining a Cylinder Head Makes Sense

Minimal Damage

Rare or Out-of-Production Parts

Budget Constraints

Limited Engine Use or Short-Term Application

Availability of High-Quality Machine Shop Services

Important Considerations When Choosing a Machine Shop

Final Thoughts: The Smarter Investment

Read More

How to Extend the Life of Your Caterpillar 3512 Marine Engine

January 31, 2025

Long-Term Care Strategies for Getting the Most Out of Your Engine

1. Prioritize Cooling System Maintenance

Signs of a Failing Raw Water Pump

Raw Water Pump Maintenance Tips

2. Perform Regular Oil & Filter Changes

Best Practices for Oil & Filter Changes

3. Keep the Fuel System Clean for Maximum Efficiency

4. Inspect & Maintain the Turbocharger

Turbocharger Maintenance Tips

5. Monitor Cylinder Heads & Perform Routine Overhauls

Signs That a Rebuild is Necessary

Benefits of Using a Caterpillar 3512 Rebuild Kit

6. Follow a Strict Preventive Maintenance Schedule

Essential Maintenance Schedule for the Caterpillar 3512

Final Thoughts: Maximize Engine Life with Proper Cooling & Maintenance

Key Takeaways

Looking for a Raw Water Pump or Rebuild Kit for Your Caterpillar 3512?

Parts Catalog for Caterpillar 3512 Marine Engine

Read More

How to Improve Fuel Efficiency in Your Caterpillar 3512 Marine Engine

January 31, 2025

Practical steps to optimize fuel usage without sacrificing performance

1. Optimize the Fuel System for Maximum Efficiency

Key Fuel System Maintenance Steps:

2. Maintain the Turbocharger for Better Airflow & Combustion

Turbocharger Maintenance Tips

3. Keep the Aftercooler Clean to Prevent Overheating

Aftercooler Maintenance Tips:

4. Reduce Engine Idling & Optimize Load Management

How to Reduce Fuel Waste from Idling:

5. Maintain the Cooling System to Avoid Overheating & Inefficiency

Cooling System Maintenance Tips:

6. Use High-Quality Aftermarket Parts for Cost-Effective Maintenance

Essential Aftermarket Parts for Fuel Efficiency:

Final Thoughts: Maximizing Fuel Efficiency in the Caterpillar 3512

Key Takeaways:

Looking for Fuel System & Performance Parts for Your 3512?

Parts Catalog for CAT 3512

Read More