1 hour ago
The Legacy of the Fiat-Allis 11B
The Fiat-Allis 11B crawler dozer was a product of the merger between Fiat of Italy and Allis-Chalmers of the United States, forming Fiat-Allis in the early 1970s. This collaboration aimed to combine European design sensibilities with American ruggedness, producing machines that could compete globally in the earthmoving sector. The 11B was introduced as a mid-size dozer, often used in road building, land clearing, and mining support. With an operating weight of approximately 22 tons and a drawbar pull exceeding 70,000 pounds, it was a workhorse in its class.
The 11B was powered by either the Allis-Chalmers 11000 series diesel engine or, in later variants, an Iveco FA engine. These engines were known for their torque-heavy performance, making them ideal for pushing large volumes of material. However, as emissions standards tightened and fuel efficiency became a priority, many operators sought to retrofit or replace components like the turbocharger to improve performance.
Understanding the Turbocharger Role
A turbocharger is a forced induction device that increases an engine’s efficiency and power output by forcing extra air into the combustion chamber. In diesel engines like those found in the 11B, turbochargers help maintain torque at lower RPMs and improve fuel economy under load. The turbocharger typically consists of a turbine housing, compressor housing, and a center cartridge containing the shaft and bearings.
In the case of the Fiat-Allis 11B, the original turbocharger may have been manufactured by Air Research or Garrett, both known for producing robust units for industrial applications. However, sourcing these parts decades later presents challenges, especially when housings or cartridges are no longer in production.
Challenges in Sourcing Replacement Units
Owners of aging 11B dozers often face difficulty finding compatible turbochargers. The original manufacturer may no longer support the model, and aftermarket suppliers may not carry exact-fit replacements. In some cases, only the cartridge—the internal rotating assembly—is available, while the compressor and turbine housings must be reused or custom-fabricated.
One operator from Missouri recounted how he managed to rebuild his turbocharger using a cartridge sourced from a regional supplier, but had to machine the housings to fit. The process took over a week and required precision balancing to avoid vibration and premature bearing failure.
Identifying the Engine Variant
Before sourcing a turbocharger, it’s critical to identify which engine variant the 11B uses. The early models featured the Allis-Chalmers 11000 series, a robust inline-six diesel with mechanical fuel injection. Later models transitioned to the Iveco FA series, which introduced electronic controls and different turbo configurations.
To determine the engine type:
Recommended Suppliers and Strategies
While OEM support has dwindled, several aftermarket and legacy parts suppliers still offer solutions:
Some operators consider upgrading to modern turbochargers with variable geometry or ball-bearing cartridges. While these can improve spool time and efficiency, they often require custom tuning and may not be compatible with the original fuel delivery system. Overboosting can lead to engine damage, including cracked pistons or blown head gaskets.
A contractor in Georgia once installed a high-performance turbo on his 11B, only to find that the fuel pump couldn’t keep up, leading to lean combustion and overheating. He eventually reverted to a stock-style unit after consulting with a diesel specialist.
Historical Anecdotes and Industry Trends
The decline of Fiat-Allis in the late 1980s mirrored broader shifts in the construction equipment industry. As global competition intensified, many legacy brands were absorbed or phased out. Fiat-Allis was eventually folded into Fiat-Hitachi, and later CNH Industrial, leaving a trail of orphaned machines with limited support.
In 1992, a fleet manager in Alberta purchased five 11Bs for a highway expansion project. By 2000, only two remained operational, largely due to parts scarcity. He recalled scavenging turbochargers from retired units and even adapting a marine diesel turbo to keep one dozer running through the winter.
Final Recommendations
For those maintaining a Fiat-Allis 11B today, the key is proactive parts management and community networking. Joining equipment owner groups, attending auctions, and building relationships with rebuild shops can extend the life of these machines.
Before replacing a turbocharger:
The Fiat-Allis 11B crawler dozer was a product of the merger between Fiat of Italy and Allis-Chalmers of the United States, forming Fiat-Allis in the early 1970s. This collaboration aimed to combine European design sensibilities with American ruggedness, producing machines that could compete globally in the earthmoving sector. The 11B was introduced as a mid-size dozer, often used in road building, land clearing, and mining support. With an operating weight of approximately 22 tons and a drawbar pull exceeding 70,000 pounds, it was a workhorse in its class.
The 11B was powered by either the Allis-Chalmers 11000 series diesel engine or, in later variants, an Iveco FA engine. These engines were known for their torque-heavy performance, making them ideal for pushing large volumes of material. However, as emissions standards tightened and fuel efficiency became a priority, many operators sought to retrofit or replace components like the turbocharger to improve performance.
Understanding the Turbocharger Role
A turbocharger is a forced induction device that increases an engine’s efficiency and power output by forcing extra air into the combustion chamber. In diesel engines like those found in the 11B, turbochargers help maintain torque at lower RPMs and improve fuel economy under load. The turbocharger typically consists of a turbine housing, compressor housing, and a center cartridge containing the shaft and bearings.
In the case of the Fiat-Allis 11B, the original turbocharger may have been manufactured by Air Research or Garrett, both known for producing robust units for industrial applications. However, sourcing these parts decades later presents challenges, especially when housings or cartridges are no longer in production.
Challenges in Sourcing Replacement Units
Owners of aging 11B dozers often face difficulty finding compatible turbochargers. The original manufacturer may no longer support the model, and aftermarket suppliers may not carry exact-fit replacements. In some cases, only the cartridge—the internal rotating assembly—is available, while the compressor and turbine housings must be reused or custom-fabricated.
One operator from Missouri recounted how he managed to rebuild his turbocharger using a cartridge sourced from a regional supplier, but had to machine the housings to fit. The process took over a week and required precision balancing to avoid vibration and premature bearing failure.
Identifying the Engine Variant
Before sourcing a turbocharger, it’s critical to identify which engine variant the 11B uses. The early models featured the Allis-Chalmers 11000 series, a robust inline-six diesel with mechanical fuel injection. Later models transitioned to the Iveco FA series, which introduced electronic controls and different turbo configurations.
To determine the engine type:
- Check the engine block for stamped serial numbers.
- Look for manufacturer tags near the valve cover or injection pump.
- Compare intake and exhaust manifold layouts to known diagrams.
Recommended Suppliers and Strategies
While OEM support has dwindled, several aftermarket and legacy parts suppliers still offer solutions:
- MinnPar: Known for stocking parts for discontinued construction equipment, including Fiat-Allis models.
- Turbo rebuild specialists: Some regional shops can rebuild or fabricate turbo components if provided with core parts.
- Salvage yards: Older units may be cannibalized for usable turbochargers, though condition and compatibility must be verified.
- Engine model and serial number
- Turbocharger part number (if available)
- Measurements of flange diameters and bolt patterns
- Desired performance characteristics (e.g., boost pressure, RPM range)
- Cartridge: The central rotating assembly of the turbocharger, including the shaft, bearings, and wheels.
- Compressor Housing: The cold side of the turbo, where air is drawn in and compressed.
- Turbine Housing: The hot side, where exhaust gases spin the turbine wheel.
- Boost Pressure: The amount of pressure above atmospheric that the turbo supplies to the intake.
- Wastegate: A valve that limits boost pressure by diverting exhaust flow away from the turbine.
Some operators consider upgrading to modern turbochargers with variable geometry or ball-bearing cartridges. While these can improve spool time and efficiency, they often require custom tuning and may not be compatible with the original fuel delivery system. Overboosting can lead to engine damage, including cracked pistons or blown head gaskets.
A contractor in Georgia once installed a high-performance turbo on his 11B, only to find that the fuel pump couldn’t keep up, leading to lean combustion and overheating. He eventually reverted to a stock-style unit after consulting with a diesel specialist.
Historical Anecdotes and Industry Trends
The decline of Fiat-Allis in the late 1980s mirrored broader shifts in the construction equipment industry. As global competition intensified, many legacy brands were absorbed or phased out. Fiat-Allis was eventually folded into Fiat-Hitachi, and later CNH Industrial, leaving a trail of orphaned machines with limited support.
In 1992, a fleet manager in Alberta purchased five 11Bs for a highway expansion project. By 2000, only two remained operational, largely due to parts scarcity. He recalled scavenging turbochargers from retired units and even adapting a marine diesel turbo to keep one dozer running through the winter.
Final Recommendations
For those maintaining a Fiat-Allis 11B today, the key is proactive parts management and community networking. Joining equipment owner groups, attending auctions, and building relationships with rebuild shops can extend the life of these machines.
Before replacing a turbocharger:
- Confirm engine type and turbo model
- Inspect manifold and oil line compatibility
- Consider rebuilding existing units if housings are intact
- Avoid high-performance upgrades unless fuel and cooling systems are also modified
