Replacing the Water Pump on a Genie Z45 with Ford LRG-425 EFI Engine

[MikePhua]

The Genie Z45 and Its Propane-Powered Platform
The Genie Z45 is a widely used articulating boom lift designed for aerial work in construction, maintenance, and industrial settings. Manufactured by Genie Industries, a subsidiary of Terex Corporation, the Z45 series has been in production since the early 2000s and is known for its 45-foot platform height, 360-degree rotation, and versatile powertrain options. One popular configuration includes a Ford LRG-425 EFI engine running on liquid propane—a setup favored for indoor and emissions-sensitive environments.
The Ford LRG-425 is a 2.5-liter inline-four engine originally developed for industrial and stationary applications. With electronic fuel injection (EFI) and a cast iron block, it delivers reliable torque and clean combustion when paired with propane. Despite its durability, components like the water pump are subject to corrosion and wear, especially in machines with low hours but long idle periods.
Water Pump Failure and Coolant Leakage
In one documented case, a Genie Z45 with under 600 hours began leaking coolant through a corroded section of the water pump housing. Unlike typical gasket failures or seal leaks, this issue involved a breach in the pump casing itself—likely caused by electrochemical corrosion or casting porosity. The leak manifested as antifreeze dripping from the side of the pump, bypassing traditional failure points.
Terminology annotation:

• Water pump: A belt-driven or gear-driven component that circulates coolant through the engine and radiator.
  
• Coolant: A fluid mixture (typically water and ethylene glycol) that regulates engine temperature and prevents freezing or boiling.
  
• EFI (Electronic Fuel Injection): A system that uses sensors and electronic control to deliver precise fuel amounts to the engine.
  

Identifying the Correct Replacement Pump
The challenge in sourcing a replacement pump stemmed from the lack of an engine-specific manual. While the Genie lift came with operational documentation, it did not include detailed service information for the Ford LRG-425 engine. By cross-referencing the engine serial number and platform configuration, technicians confirmed the engine model and located a compatible pump through industrial parts suppliers.
The Ford LRG-425 shares components with other Ford industrial engines, including the 2.3L and 2.5L variants used in forklifts, generators, and sweepers. Water pumps for these engines are typically cast aluminum or iron, with bolt-on flanges and integrated impellers. When ordering a replacement, verify:

• Mounting bolt pattern and flange orientation
  
• Pulley type (serpentine vs. V-belt)
  
• Hose connection sizes and angles
  
• Gasket type (paper, rubber, or metal)
  

Installation Process and Practical Advice
Replacing the water pump on the LRG-425 is relatively straightforward, provided the technician has access to basic hand tools and a clean workspace. Recommended steps include:

• Drain the coolant system completely
  
• Remove the serpentine belt or drive pulley
  
• Disconnect upper and lower radiator hoses
  
• Unbolt the water pump from the engine block
  
• Clean the mating surface and inspect for corrosion
  
• Install the new pump with a fresh gasket and torque bolts evenly
  
• Refill coolant and bleed air from the system
  

Use thread sealant on bolts if specified by the manufacturer, and always check for leaks after the first heat cycle. It’s advisable to replace the thermostat and inspect the radiator cap during pump replacement, as these components often fail in tandem.
Finding Reliable Service Documentation
While the original Genie manuals may lack engine-specific procedures, third-party resources exist. One helpful reference is the , which includes diagrams, torque specs, and cooling system details. Pages 60–63 cover water pump removal and installation, including exploded views and part numbers.
For technicians working on mixed fleets, maintaining a digital archive of engine manuals can streamline repairs. Many industrial engines are used across multiple platforms, and familiarity with one model often translates to others.
Preventive Measures and Long-Term Cooling Health
To prevent future water pump failures:

• Use coolant with corrosion inhibitors rated for aluminum and iron
  
• Flush the system every 2–3 years or 1,000 hours
  
• Avoid mixing coolant types (e.g., green ethylene glycol with orange Dex-Cool)
  
• Monitor coolant pH and conductivity during service intervals
  
• Inspect pump housing for early signs of oxidation or pitting
  

In climates with high humidity or salt exposure, consider applying anti-corrosion coatings to exposed metal surfaces. For propane-powered engines, ensure the fuel system is leak-free, as propane combustion can produce acidic byproducts that accelerate corrosion.
Conclusion
The Genie Z45 with a Ford LRG-425 EFI engine is a capable and clean-running lift, but like all machines, it requires attentive maintenance. Water pump failure due to casing corrosion is rare but serious, and replacing the pump demands careful sourcing and installation. With the right documentation, parts, and preventive practices, operators can restore cooling system integrity and keep their lifts running smoothly for years to come. Whether in a warehouse or on a jobsite, the Z45 remains a trusted tool—provided its heart, the engine, stays cool under pressure.