Diagnosing Short Runtime Issues on the New Holland LX665 Turbo Skid Steer

[MikePhua]

New Holland’s Skid Steer Heritage
New Holland entered the skid steer market in the 1970s, quickly gaining traction with its patented Super Boom design, which offered superior vertical lift and reach. The LX665 Turbo, part of the LX600 series introduced in the late 1990s, became a popular mid-frame model for contractors, landscapers, and agricultural users. Powered by a turbocharged diesel engine—typically a 3-cylinder New Holland or ISM engine—it delivered around 60 horsepower and featured hydraulic quick-attach, auxiliary hydraulics, and a rated operating capacity of approximately 1,700 pounds.
By the early 2000s, New Holland had sold tens of thousands of LX-series units globally, with the LX665 Turbo standing out for its balance of power, compact footprint, and service accessibility. The company itself, founded in Pennsylvania in 1895, had evolved through mergers with Ford and Fiat, eventually becoming part of CNH Industrial, a global leader in agricultural and construction equipment.
Symptoms of Short Runtime and Engine Shutdown
A common issue reported with the LX665 Turbo is that the engine starts normally but shuts down within 30 seconds. This symptom can be frustrating, especially when the machine appears mechanically sound. The short runtime points to a failure in one or more of the following systems:

• Fuel delivery system
  
• Electrical safety interlocks
  
• Engine control module (ECM) or sensor feedback
  
• Air intake restriction or turbo malfunction
  

The fact that the engine starts and runs briefly suggests that initial combustion is successful, but a feedback loop or safety override is interrupting continued operation.
Fuel System Troubleshooting
Start with the basics:

• Fuel filter: A clogged filter can restrict flow, especially after startup when demand increases. Replace with OEM-rated filters and inspect for water or debris.
  
• Lift pump: If the mechanical or electric lift pump is weak, it may supply enough fuel for startup but fail under load. Use a pressure gauge to verify consistent delivery.
  
• Fuel solenoid: This electrically actuated valve controls fuel flow to the injection pump. If it loses power or sticks, the engine will shut down. Test voltage at the solenoid during startup and after 30 seconds.
  

In one case, a contractor in Maryland discovered that a corroded ground wire to the fuel solenoid was intermittently breaking contact. After cleaning and resealing the connection, the machine ran flawlessly.
Electrical Interlocks and Safety Systems
New Holland skid steers are equipped with multiple safety switches to prevent operation under unsafe conditions. These include:

• Seat switch: Detects operator presence.
  
• Seatbelt switch: Ensures the operator is secured.
  
• Boom lockout switch: Prevents movement if the boom is raised during startup.
  
• Parking brake sensor: Confirms brake engagement before hydraulic activation.
  

If any of these switches are faulty or misaligned, the ECM may interpret the condition as unsafe and shut down the engine. Use a multimeter to test continuity and voltage across each switch. Bypass testing (with caution) can help isolate the faulty component.
Air Intake and Turbocharger Inspection
Turbocharged engines rely on clean, unrestricted airflow. A blocked air filter or malfunctioning turbo can cause the engine to stall shortly after ignition.

• Air filter: Inspect for clogging, oil saturation, or rodent nesting.
  
• Turbocharger: Check for shaft play, oil leaks, and free rotation. A seized turbo can choke airflow and trigger shutdown.
  
• Intake manifold pressure sensor: If this sensor fails, the ECM may misread boost levels and cut fuel delivery.
  

A technician in Wisconsin once found that a mud dauber nest had formed inside the intake snorkel of an LX665 parked for the winter. The obstruction caused erratic airflow and triggered shutdown until cleared.
ECM and Diagnostic Codes
If equipped with an onboard diagnostic system, retrieve fault codes using a compatible scan tool. Common shutdown codes include:

• Low fuel pressure
  
• Safety interlock failure
  
• Turbo boost deviation
  
• Overheat sensor fault
  

Even without a scan tool, some models flash error codes via dashboard lights. Refer to the service manual for blink patterns and interpretations.
Preventative Measures and Long-Term Solutions
To avoid recurrence:

• Perform seasonal electrical inspections, especially on exposed connectors.
  
• Replace fuel filters every 250 hours or annually.
  
• Clean and test safety switches quarterly.
  
• Store the machine indoors or under cover to prevent moisture intrusion.
  

Conclusion
The New Holland LX665 Turbo is a reliable workhorse, but short runtime issues often stem from overlooked electrical or fuel system faults. By methodically inspecting each subsystem—starting with fuel delivery and ending with ECM diagnostics—operators can restore functionality and avoid unnecessary downtime. These machines were built to last, and with proper care, they’ll continue to serve across fields, yards, and job sites for years to come.