Troubleshooting Lull 944E-42 Telehandler That Won’t Run After Bad Fuel

[MikePhua]

The Lull 944E-42 telehandler is a versatile piece of equipment commonly used in construction, warehousing, and other industries requiring heavy lifting and material handling. These machines are known for their ruggedness and reliability, but like any piece of machinery, they can encounter issues when the fuel system is compromised. One common problem that operators face is when the machine stops running after being contaminated with bad fuel.
Bad fuel, which may include water, dirt, or impurities, can wreak havoc on an engine's performance. This article will explore the steps involved in diagnosing and resolving fuel-related issues with a Lull 944E-42, focusing on troubleshooting procedures and essential maintenance tips.
Understanding the Problem: Bad Fuel in the System
Fuel contamination is a serious issue that can cause a variety of performance problems in diesel-powered machines, including the Lull 944E-42. Bad fuel typically refers to fuel that has been contaminated by water, dirt, or bacteria, all of which can disrupt the smooth functioning of the engine.
The most common types of bad fuel include:

1. Water Contamination: Water can enter the fuel system through leaks in the fuel tank or during the refueling process. Water in the fuel can cause poor combustion, misfires, and even damage to internal engine components.
   
2. Dirt and Debris: If the fuel tank or fuel lines become contaminated with dirt or debris, it can clog the fuel filters and injectors, leading to engine misfires or failure to start.
   
3. Bacterial Growth: Over time, especially in warmer climates, bacteria and fungi can grow in the fuel tank, especially when water is present. These microorganisms feed on the hydrocarbons in the diesel, further contaminating the fuel and leading to sludge build-up.
   

When bad fuel enters the system, the engine may experience a range of symptoms such as difficulty starting, stalling, rough idling, or a complete failure to run. These issues should be addressed immediately to prevent further damage.
Initial Steps to Address Fuel Contamination
If your Lull 944E-42 telehandler won’t run after using bad fuel, the first thing you need to do is isolate the problem. Here are the initial steps you should take:

1. Turn Off the Engine: If the engine is still running, immediately turn it off to prevent further damage.
   
2. Check the Fuel Tank: Examine the fuel tank for any signs of contamination. Look for visible water, dirt, or sludge floating on top of the fuel. If you notice anything unusual, it may indicate that the fuel is contaminated.
   
3. Drain the Fuel System: To prevent further damage, drain the fuel tank and fuel lines completely. You can do this by using a siphon pump to remove the contaminated fuel. Be sure to dispose of the bad fuel properly according to local regulations.
   
4. Inspect Fuel Filters: Fuel filters play a critical role in preventing contaminants from entering the engine. If the fuel filters are clogged with debris or water, replace them immediately.
   

Thorough Fuel System Inspection
Once the contaminated fuel is drained and the fuel tank is cleared, a more detailed inspection of the fuel system should be performed. This ensures that no residual contaminants are left to cause problems when fresh fuel is introduced.

1. Inspect the Fuel Lines: Check the entire fuel system for leaks or cracks. Over time, fuel lines can degrade and allow contaminants to enter the system. If you find any signs of damage, replace the affected fuel lines.
   
2. Check the Fuel Pump: The fuel pump is responsible for drawing fuel from the tank and supplying it to the engine. A malfunctioning pump can cause fuel delivery issues and poor engine performance. If the pump is clogged or malfunctioning due to bad fuel, it may need to be cleaned or replaced.
   
3. Clean or Replace Fuel Injectors: Bad fuel can clog fuel injectors, leading to poor fuel atomization and engine performance. Inspect the injectors for any signs of damage or clogging. Cleaning the injectors with specialized equipment may solve minor issues, but severe clogging may require a full replacement.
   
4. Inspect the Fuel Filter: Always replace the fuel filter after addressing fuel contamination. A clogged or damaged fuel filter is one of the most common reasons for fuel delivery problems. If the fuel filter is compromised, it can lead to engine misfires, poor fuel efficiency, and other performance issues.
   

Refueling with Fresh Fuel
Once the fuel system is clear of contaminants, it’s time to refill the tank with fresh, clean diesel. Always use high-quality fuel from reputable sources to prevent contamination in the future.

1. Fuel Additives: In some cases, you may want to add fuel additives to help clean the fuel system and prevent future issues. Fuel additives can help remove water, clean injectors, and improve fuel quality. However, always follow the manufacturer’s recommendations regarding which additives are safe to use with the Lull 944E-42.
   
2. Check Fuel for Contaminants: Before refueling, visually inspect the fuel for any signs of contamination. You can use a fuel filter or fuel water separator to further ensure that no debris or water enters the system.
   

Testing the Engine After Fuel System Maintenance
After completing all the necessary repairs and refueling with clean fuel, it’s time to start the engine and test its performance.

1. Crank the Engine: Start the engine and let it run at idle for a few minutes. Listen for any unusual noises or rough idling that could indicate remaining contamination in the fuel system.
   
2. Check for Leaks: Inspect the fuel lines, fuel pump, and injectors for any signs of leaks. Leaking fuel can cause serious safety hazards and should be addressed immediately.
   
3. Perform Load Testing: Once the engine is running smoothly at idle, gradually apply load to the machine. This will help you verify that the engine operates under various conditions without any issues.
   

Preventing Future Fuel Contamination Issues
To minimize the risk of future fuel contamination and ensure the longevity of your Lull 944E-42, consider implementing these preventive measures:

1. Regular Fuel Quality Checks: Periodically inspect the fuel for signs of contamination, especially if the machine has been sitting idle for an extended period. Use a fuel/water separator and water detection sensors to catch contamination early.
   
2. Proper Fuel Storage: Always store fuel in clean, well-sealed containers and avoid leaving fuel exposed to moisture or contaminants.
   
3. Frequent Fuel System Maintenance: Regularly replace fuel filters and inspect the fuel system for leaks or signs of wear. Clean the fuel injectors as needed to maintain optimal engine performance.
   
4. Use High-Quality Diesel Fuel: Always use high-quality diesel fuel from trusted suppliers. Fuel with a low sulfur content and additives that prevent microbial growth is ideal.
   

Conclusion
Fuel contamination is a common issue that can cause significant damage to your Lull 944E-42 telehandler’s engine and fuel system. If the machine won’t run after being exposed to bad fuel, it’s essential to take immediate action by draining the contaminated fuel, inspecting the fuel system, and refueling with fresh, clean fuel. Regular maintenance and proper fuel handling practices can go a long way in preventing fuel-related problems in the future, keeping your Lull 944E-42 running smoothly and efficiently for years to come.