Ford A62 Loader Fuel Injection Troubles and Mechanical Remedies

[MikePhua]

The Ford A62 and Its Industrial Role
The Ford A62 wheel loader was part of Ford’s push into the heavy equipment market during the 1970s and early 1980s. Built for municipal, agricultural, and light construction use, the A62 featured a robust articulated frame, planetary axles, and a torque converter transmission. Its powerplant—a Ford diesel engine, often the BSD 444 or BSD 442—was known for mechanical simplicity and field serviceability. Though production numbers were modest compared to competitors like Caterpillar or Case, the A62 earned a reputation for reliability in small fleets and rural operations.
Today, many A62s remain in service, especially in North America, where parts and rebuild kits are still available through legacy suppliers. However, as these machines age, fuel injection issues have become increasingly common, often manifesting as hard starts, erratic idle, or complete failure to run.
Terminology Annotation

• Injection Pump: A mechanical device that meters and pressurizes diesel fuel for delivery to the injectors.
  
• Fuel Solenoid: An electrically actuated valve that allows or blocks fuel flow into the pump, often used for engine shutoff.
  
• Lift Pump: A low-pressure pump that draws fuel from the tank and feeds it to the injection pump.
  
• Return Line: A hose that allows excess fuel to flow back to the tank, relieving pressure and preventing vapor lock.
  

Common Symptoms and Diagnostic Pathways
Operators may encounter:

• Engine cranks but fails to start
  
• Starts briefly then stalls
  
• Requires ether or excessive cranking to fire
  
• Fuel visible at injectors but no combustion
  
• Solenoid clicks but no fuel delivery
  

In one documented case, an A62 loader started intermittently and would die after 30 seconds. The fuel solenoid was receiving voltage, but the internal plunger was stuck due to varnish buildup. Cleaning the solenoid and replacing the rubber seal restored normal operation.
Fuel Solenoid and Electrical Integrity
The fuel solenoid is a critical component in the injection system. It must receive 12V power during cranking and running. If the solenoid fails to open, fuel cannot enter the pump.
Checklist:

• Test voltage at solenoid terminal during key-on and crank
  
• Listen for audible click when energized
  
• Remove solenoid and inspect plunger for movement
  
• Clean with diesel-safe solvent and replace O-rings
  
• Bypass solenoid temporarily to confirm diagnosis
  

In one fleet, a loader had a broken wire inside the loom near the firewall. Though voltage was present at the ignition switch, it never reached the solenoid. Rewiring the circuit resolved the issue.
Injection Pump Wear and Internal Failure
If the solenoid is functional but fuel delivery remains erratic, the injection pump may be worn or internally damaged. Common causes include:

• Water contamination leading to rusted plungers
  
• Varnish buildup from old diesel
  
• Worn governor linkage
  
• Broken internal springs or seized metering valve
  

Solutions:

• Remove pump and bench test with a calibrated fuel rig
  
• Replace seals and plungers using a rebuild kit
  
• Flush fuel system and replace filters
  
• Use diesel conditioner to clean internal passages
  

In one restoration, a technician rebuilt a CAV rotary pump using a kit sourced from a UK supplier. After reinstallation and timing adjustment, the loader started reliably and ran smoothly under load.
Lift Pump and Fuel Supply Integrity
The lift pump must deliver fuel at low pressure to the injection pump. If it fails, the injection pump may cavitate or run dry.
Diagnostic steps:

• Disconnect inlet line and check flow during cranking
  
• Inspect for air bubbles or fuel foaming
  
• Replace diaphragm or entire pump if flow is weak
  
• Check tank pickup for blockage or collapsed hose
  

In one case, a loader had a kinked fuel line under the cab, restricting flow. Replacing the hose and adding a pre-filter restored consistent fuel delivery.
Return Line and Pressure Regulation
The return line prevents pressure buildup and allows unused fuel to circulate. If blocked, the injection pump may flood or stall.
Recommendations:

• Inspect return line for kinks or clogs
  
• Blow compressed air through line to confirm flow
  
• Replace banjo bolts and washers if leaking
  
• Ensure return port on pump is clear
  

Some operators install transparent return lines to monitor flow visually during startup.
Preventative Measures and Upgrade Suggestions
To maintain fuel system health:

• Use diesel stabilizer in seasonal equipment
  
• Replace filters every 250 hours or annually
  
• Drain water separators regularly
  
• Install inline pressure gauge for diagnostics
  
• Upgrade to electric lift pump for consistent priming
  

In colder climates, adding a fuel heater or using winter-grade diesel prevents gelling and hard starts.
Conclusion
Fuel injection issues in the Ford A62 loader are often rooted in solenoid failure, pump wear, or supply restrictions. With methodical diagnosis and attention to electrical and hydraulic integrity, most problems can be resolved without major overhaul. The A62’s mechanical design allows for field service and component replacement, preserving its utility decades after production ended. In the world of legacy loaders, clean fuel and clean connections keep the iron moving.