Removing the Radiator from an International TD-7 Dozer

[MikePhua]

The TD-7 and Its Cooling System Design
The International TD-7 crawler dozer was part of International Harvester’s mid-sized track-type tractor lineup, introduced in the 1960s and refined through the 1980s. Designed for grading, land clearing, and light earthmoving, the TD-7 featured a compact frame, a 4-cylinder diesel engine, and a front-mounted radiator tucked behind a protective grille and hydraulic cooler. Its cooling system was engineered for durability, but decades of vibration, corrosion, and sediment buildup can lead to leaks—especially around the lower neck and hose connections.
The radiator in the TD-7 is a vertical-flow unit with a top tank, core, and bottom outlet. It interfaces with the engine via upper and lower hoses and is often paired with an oil cooler mounted in front or below. The entire assembly is bolted to the front frame and shrouded by sheet metal guards.
Terminology annotation:

• Vertical-flow radiator: A cooling unit where coolant flows from top to bottom through tubes and fins.
  
• Oil cooler: A heat exchanger that reduces hydraulic or engine oil temperature.
  
• Neck: The outlet or inlet pipe on the radiator tank where hoses connect.
  
• Shroud: A protective cover that directs airflow and shields components.
  

Common Leak Points and Removal Challenges
Leaks around the bottom neck of the radiator are common in older TD-7 units. These may result from:

• Cracked solder joints or brazed seams
  
• Hose clamp fatigue or misalignment
  
• Electrochemical corrosion from mixed coolant types
  
• Vibration-induced stress fractures
  

Removing the radiator is deceptively complex. While it may appear that the cooler can be pulled forward, the process is obstructed by overlapping sheet metal, hydraulic lines, and the oil cooler. Operators often find that access is limited and clearance is tight, especially if the machine has aftermarket guards or modifications.
Recommended Removal Procedure
To remove the radiator safely and efficiently:

• Disconnect the battery to prevent accidental shorts
  
• Drain the coolant completely using the petcock or lower hose
  
• Remove the upper and lower radiator hoses
  
• Detach the oil cooler lines if mounted to the radiator frame
  
• Unbolt the sheet metal shroud and grille assembly
  
• Support the radiator with a hoist or jack before unbolting mounts
  
• Remove mounting bolts from the radiator base and top brackets
  
• Carefully slide the radiator forward, watching for snags on hoses or wiring
  

If the oil cooler is integrated or obstructing removal, it may need to be detached first. Use flare nut wrenches to avoid rounding hydraulic fittings, and plug lines to prevent contamination.
Field Anecdote and Practical Insight
One operator in Tennessee discovered a persistent leak near the bottom neck of his TD-7 radiator. After pulling the lower hose and inspecting the joint, he suspected a crack in the tank seam. While it appeared the cooler could be removed through the front, experience taught him that nothing is ever that simple. Sheet metal guards had to be removed, and the oil cooler was partially blocking the path. With patience and a second set of hands, he managed to extract the radiator and send it to a local shop for re-soldering.
This kind of repair is common in legacy equipment. Radiator shops can often rebuild or re-core older units, preserving the original tanks and fittings. In some cases, custom aluminum replacements are fabricated, though these may require bracket modifications.
Preventive Maintenance and Long-Term Solutions
To extend radiator life and reduce future failures:

• Flush the cooling system annually to remove sediment
  
• Use coolant with corrosion inhibitors rated for mixed-metal systems
  
• Inspect hose clamps and replace every 2–3 years
  
• Add rubber isolators to mounting brackets to reduce vibration
  
• Monitor coolant level and color for signs of oil contamination or rust
  

For machines operating in dusty or brush-heavy environments, consider installing mesh guards to prevent debris buildup in the fins. Overheating due to clogged airflow is a leading cause of radiator stress.
International Harvester Legacy and Parts Support
International Harvester, founded in 1902, was a pioneer in agricultural and construction machinery. The TD series dozers were known for their rugged simplicity and were widely used across North America. After the company’s merger into Case IH and later Navistar, parts support became fragmented. However, many aftermarket suppliers still stock components for TD-7 models, including radiators, hoses, and cooling system hardware.
Operators restoring vintage TD-7s often rely on salvage yards, online forums, and fabrication shops to source or rebuild parts. The radiator, while critical, is one of the more serviceable components thanks to its modular design and rebuild potential.
Conclusion
Removing the radiator from an International TD-7 dozer requires patience, planning, and a clear understanding of the machine’s layout. While the task may seem straightforward, hidden fasteners, tight clearances, and integrated oil coolers can complicate the process. With careful disassembly and attention to detail, the radiator can be removed, repaired, and reinstalled—restoring the cooling system and extending the life of this classic crawler. For those committed to keeping vintage iron alive, mastering these repairs is part of the journey.