Diagnosing No-Start Conditions on the Genie GTH-844 with Deutz BF4M2012 Engine

[MikePhua]

Genie GTH-844 Telehandler Overview
The Genie GTH-844 is a widely used rough-terrain telehandler designed for lifting, placing, and transporting materials on construction sites. Manufactured by Genie Industries, a subsidiary of Terex Corporation, the GTH-844 features a maximum lift capacity of 8,000 lbs and a reach height of 44 feet. It’s powered by a Deutz BF4M2012 diesel engine, a four-cylinder, direct-injection unit known for its compact design and mechanical reliability.
Genie telehandlers have been deployed across North America and Europe in both rental fleets and contractor-owned operations. The GTH-844, in particular, is favored for its balance of lifting power and maneuverability in tight or uneven terrain.
Terminology Annotation

• BF4M2012: A Deutz four-cylinder diesel engine with mechanical injection and an EMR-2 electronic governor system.
  
• EMR-2 Governor: Electronic Motor Regulation system that controls fuel delivery and engine speed via solenoids and sensors.
  
• Injection Pump: A mechanical or electronically assisted pump that delivers pressurized fuel to the injectors.
  
• Lift Pump: A low-pressure pump that supplies fuel from the tank to the injection system.
  

Symptoms of Cranking Without Start
A common issue reported with the GTH-844 is that the engine cranks normally but fails to start. In one case, fuel was present at the front two injection pumps but absent at the rear two. This uneven distribution raised concerns about fuel delivery, pump integrity, and camshaft condition.
Typical symptoms include:

• Engine cranks at normal speed but does not fire
  
• Fuel present at some injection ports but not others
  
• No diagnostic support from the Genie manual, which defers to the engine manufacturer
  
• Shutoff solenoid located between rear injection pumps, possibly interfering with fuel flow
  

Possible Causes and Diagnostic Strategy
To resolve a no-start condition, technicians should consider the following possibilities:

• Insufficient fuel pressure to rear injection pumps due to clogged lines or weak lift pump
  
• Mechanical failure in the injection pump, such as worn plungers or broken springs
  
• Camshaft lobe damage preventing proper actuation of rear pump elements
  
• Faulty shutoff solenoid preventing fuel delivery to rear cylinders
  
• Airlock in the fuel system due to low tank level or improper priming
  

Recommended diagnostic steps:

• Loosen inlet fittings at rear injection pumps and observe fuel flow during cranking
  
• Check for strong fuel delivery from the lift pump to all injection ports
  
• Inspect shutoff solenoid for proper operation and voltage supply
  
• Remove valve cover and inspect camshaft lobes for wear or damage
  
• Prime the fuel system thoroughly, especially after refueling or filter replacement
  

In one case, the issue was resolved simply by adding more fuel and re-priming the system. This suggests that airlock or low fuel level can mimic more serious mechanical faults.
Field Anecdotes and Practical Advice
In Michigan, a technician encountered a similar issue on a military generator powered by a Deutz engine. After replacing the shutoff solenoid and manually priming the system, the engine started immediately. He noted that the EMR-2 governor system can be sensitive to voltage fluctuations and grounding issues.
In South Carolina, a pump rebuilder emphasized that uneven fuel delivery often points to camshaft wear or broken lobes. He recommended checking for fuel spurting from each injection pump inlet during cranking—there should be a strong, rhythmic pulse.
In Ontario, a rental fleet manager found that belt-driven lift pumps on older Deutz engines can fail silently. Replacing the pump restored fuel pressure and resolved multiple no-start complaints.
Preventive Measures and Long-Term Reliability
To avoid future starting issues:

• Keep fuel tank above one-third full to prevent air ingestion
  
• Replace fuel filters every 250 hours or as recommended
  
• Inspect and clean shutoff solenoid connections quarterly
  
• Prime fuel system after any service involving fuel lines or filters
  
• Monitor cranking speed—low RPM may indicate battery or starter issues
  

Operators should also document fuel system repairs and solenoid replacements, as these components often fail intermittently before complete failure.
Conclusion
A Genie GTH-844 telehandler that cranks but won’t start is often suffering from uneven fuel delivery, solenoid malfunction, or airlock. With a structured diagnostic approach—starting from fuel flow and progressing to camshaft inspection—technicians can isolate the fault and restore operation. The Deutz BF4M2012 engine, while reliable, requires careful attention to priming and solenoid function. For fleet managers and operators, understanding the nuances of this engine’s fuel system is key to minimizing downtime and ensuring consistent performance.