Reviving an Old CAT D2 Barn Find: A Restoration Journey

[MikePhua]

Introduction to the CAT D2
The CAT D2 is a vintage crawler tractor that has been a staple in construction and agricultural operations since its introduction. Known for its durability and power, this model has stood the test of time. However, like many older machines, it can fall into disrepair if left unused for extended periods. In this article, we’ll explore the process of reviving a barn-find CAT D2, bringing it back to life after years of neglect.
Step 1: Assess the Overall Condition

1. Visual Inspection
   • Before diving into the mechanical repairs, it’s important to perform a thorough visual inspection. Look for any major signs of damage, such as cracked frames, bent or rusted components, and damaged parts that might be beyond repair.
     
2. Rust and Corrosion
   • Rust is a common issue in older machines, especially if they’ve been sitting idle for years. Check the undercarriage, the engine compartment, and any exposed metal parts for corrosion.
     
3. Solution
   • Clean off any visible rust, and use a rust remover or sandblasting to address areas that need more intensive treatment. If the damage is extensive, parts may need to be replaced or welded.
     

Step 2: Inspect the Engine

1. Engine Condition
   • The engine is one of the most critical parts of any machine, and it is essential to inspect it thoroughly. If the CAT D2 has been sitting for years, the engine may have seized up, or it could be locked due to old oil or lack of lubrication.
     
2. Check Oil Levels and Condition
   • Start by checking the oil level and condition. Old, thickened oil may prevent proper engine function. If the oil is black and gritty, it’s a sign that it’s past its usable life.
     
3. Solution
   • Drain the old oil and replace it with fresh oil. Turn the engine over by hand or use a manual starter to ensure that it isn’t seized. If the engine is stuck, applying a small amount of penetrating oil to the cylinders can help loosen it up.
     

Step 3: Inspect the Fuel System

1. Fuel Lines and Filters
   • Fuel system issues are common in barn-find machines. Over time, fuel lines can become clogged, and filters can get dirty, preventing the fuel from reaching the engine.
     
2. Check Fuel Tank and Lines
   • Inspect the fuel tank for rust, debris, or old fuel. Check the fuel lines for cracks, leaks, or blockages.
     
3. Solution
   • Clean the fuel tank and flush the fuel lines. Replace any damaged or cracked lines and replace the fuel filter to ensure proper flow to the engine. Also, be sure to use fresh fuel before attempting to start the engine.
     

Step 4: Examine the Electrical System

1. Check the Battery and Wiring
   • After years of inactivity, the electrical system may be in poor condition. Check the battery for corrosion, leakage, and overall functionality. Inspect the wiring for fraying or damage, especially around the starter and alternator.
     
2. Solution
   • Clean the battery terminals and replace the battery if it is no longer holding a charge. If the wiring is damaged, it may need to be repaired or replaced to ensure the electrical system works properly.
     

Step 5: Inspect the Hydraulic System

1. Hydraulic Fluid and Leaks
   • If the CAT D2 uses a hydraulic system, it’s important to check the fluid levels and look for leaks. Stale or contaminated hydraulic fluid can cause the system to perform poorly or fail completely.
     
2. Check the Hydraulic Lines
   • Inspect the hydraulic hoses and lines for any signs of leaks or cracks. Ensure that the hydraulic cylinder and pump are functioning as expected.
     
3. Solution
   • Replace old hydraulic fluid and top up the system to the recommended level. If there are any leaks, repair or replace the affected hoses or seals.
     

Step 6: Address the Undercarriage and Tracks

1. Inspect the Tracks and Sprockets
   • The undercarriage is crucial for the mobility of the CAT D2. Over time, the tracks can become worn down, and the sprockets may be damaged.
     
2. Check for Track Tension
   • Check the track tension and make sure the tracks are not too tight or too loose. Inspect the sprockets and rollers for any visible wear.
     
3. Solution
   • If the tracks are damaged or worn, they may need to be replaced. Clean and lubricate the undercarriage to prevent further damage. Adjust the track tension as needed to ensure smooth operation.
     

Step 7: Test the Hydraulic Steering and Final Drive

1. Hydraulic Steering Function
   • The hydraulic steering system is another vital part of the CAT D2. If the machine hasn’t been used in a while, the hydraulic steering could be slow or non-functional.
     
2. Check the Final Drive
   • Inspect the final drive for any signs of leakage, damage, or wear. The final drive is essential for transferring power from the engine to the tracks.
     
3. Solution
   • If the hydraulic steering isn’t functioning properly, check the system for leaks or low fluid levels. Refill and bleed the system as necessary. Inspect and repair the final drive as needed to ensure the tracks turn smoothly.
     

Step 8: Perform a Test Run

1. Initial Start-up
   • After completing the repairs and inspections, it’s time to test the machine. Start the engine and listen for any unusual sounds. Check for fluid leaks and monitor the engine’s response to throttle adjustments.
     
2. Test the Functionality
   • Test the operation of the tracks, steering, and hydraulics. Ensure that the CAT D2 can move forward and backward without hesitation, and check that the hydraulic system functions smoothly.
     
3. Solution
   • If the machine starts and runs well, you’ve successfully revived your barn-find CAT D2! If issues persist, further troubleshooting may be necessary to pinpoint and fix the problem.
     

Conclusion
Restoring an old CAT D2 barn find is a rewarding project that requires patience and attention to detail. By following the steps outlined in this guide, you can bring this vintage machine back to life and restore its full functionality. Whether you're a collector, hobbyist, or simply looking to put the machine back to work, a well-restored CAT D2 can provide years of reliable service.