Starting Troubles on a 1973 International 175C Track Loader

[MikePhua]

Quick answer
If pressing the starter button on a 1973 International 175C only produces a click without cranking, the issue likely lies in the starter solenoid, battery connections, or ground path. Begin by inspecting all cables and terminals under the seat and at the starter itself.
International Harvester 175C background and electrical system
The International 175C was a mid-sized track loader produced by International Harvester during the early 1970s. It was designed for excavation, material handling, and site preparation, competing with Caterpillar’s 955 and John Deere’s 755 series. The 175C featured:

• A DT-466 diesel engine (or earlier D-407 in some units)
  
• Direct-drive transmission with torque converter
  
• Mechanical linkage controls
  
• 24V electrical system with dual batteries
  
• Delco-style starter motor with remote solenoid
  

The machine was built for rugged use, but its electrical system—especially the starter circuit—can degrade over time due to corrosion, vibration, and age.
Starter circuit behavior and common failure points
When the starter button is pressed and only a click is heard, the solenoid may be engaging but the starter motor is not turning. This points to one of several issues:

• Weak battery voltage: Insufficient current to turn the starter
  
• Corroded terminals: High resistance at battery or starter connections
  
• Faulty solenoid: Internal contact failure despite audible click
  
• Bad ground path: Frame-to-battery ground may be loose or rusted
  
• Stuck starter motor: Brushes or armature may be worn or jammed
  

On the 175C, the starter circuit runs from the battery under the seat to the starter on the right side of the engine. The seat cushion must be lifted to access the battery terminals and inspect for smoke, heat, or loose connections.
Diagnostic steps and repair strategy
To isolate the fault:

• Check battery voltage: Each battery should read 12.6V or higher at rest
  
• Inspect terminals: Clean all cable ends with a wire brush and tighten securely
  
• Test solenoid: Use a jumper wire to bypass the starter button and trigger the solenoid directly
  
• Tap the starter: A light hammer tap may free stuck brushes
  
• Check ground strap: Ensure the frame ground is clean and tight
  

If the starter still fails to turn, remove it for bench testing. A rebuilt Delco-style starter is often available from agricultural or truck parts suppliers.
Preventive measures and upgrade options

• Replace old battery cables with heavy-gauge copper
  
• Install a battery disconnect switch to prevent parasitic drain
  
• Use dielectric grease on terminals to prevent corrosion
  
• Upgrade to a gear-reduction starter for better cold-start torque
  

One operator in Colorado restored his 175C by replacing the starter with a modern gear-reduction unit and installing a new ground strap directly to the transmission housing. The machine started reliably even in sub-freezing temperatures.
Conclusion
A 1973 International 175C that clicks but won’t crank likely suffers from starter circuit degradation. Begin with battery and cable inspection, then test the solenoid and starter motor. With proper diagnosis and a few upgrades, this classic track loader can return to dependable service.