🔧 APS Preinstallation Guide: How to Properly Install a Used Engine

At AutoPowerSource, we want your replacement engine to run smoothly and last for years. That’s why we’ve created this simple but essential Used Engine Preinstallation Guide — to help you avoid costly mistakes and ensure warranty coverage.

Whether you're a mechanic or a DIY installer, following these steps is critical to protect your investment and get the most life out of your used engine.

✅ Step-by-Step Installation Checklist for Used Engines

⚠️ Important: Failure to follow this guide can void your warranty. Always use professional-grade tools, fluids, and safety practices.

🔧 1. Replace Timing Components & Seals

Start fresh with new timing components. We strongly recommend replacing:

  • Timing belt or chain
  • Crankshaft seals (front and rear)
  • Camshaft seals
  • Valve cover gasket
  • Oil pan gasket
  • Intake manifold gasket

Worn seals and timing components are the #1 cause of early engine failure after installation. Don’t skip this step.

🔄 2. Transfer All Accessories from Your Old Engine

Move the following components from your original engine to the replacement:

  • Sensors
  • Brackets
  • Pulleys
  • Belts
  • Mounts

⚠️ The accessories that come with your used engine are not covered under warranty and may be damaged or incorrect for your vehicle. Always reuse your original parts when possible.

💧 3. Replace Water Pump & Thermostat

Cooling issues are a common cause of failure in reused engines. To protect your new engine:

  • Install a new water pump
  • Replace the thermostat
  • Fill the system with a 50/50 mix of antifreeze and water
  • Pressure-test the system for leaks before startup

🧼 4. Clean the Intake Manifold & Ports

Thoroughly clean your intake manifold. Also:

  • Inspect intake and exhaust ports for debris
  • Remove any broken bolts, gaskets, or loose metal pieces

⚠️ Debris from a failed engine can get sucked into the new one and cause instant damage. This is the installer's responsibility.

🛢️ 5. Use Fresh Oil & Filter

  • Before starting the engine:
  • Install a new oil filter
  • Add fresh engine oil
  • After startup, change the oil and filter every 3,000 miles, or as recommended by the vehicle manufacturer
  • Never go over 5,000 miles between oil changes
  • Keep all receipts for oil and filter changes for warranty purposes

🔍 6. Final Pre-Startup Inspection

  • Double-check everything before first crank:
  • Confirm all sensors and connectors are properly plugged in
  • Make sure all bolts are torqued to spec
  • Prime the engine with oil (especially if it’s been stored)
  • Crank the engine without starting to build oil pressure safely

🧰 Final Thoughts: Protect Your Investment

Installing a used engine is a big job — but it doesn’t have to be a risky one. By following these preinstallation steps, you reduce the chances of failure and keep your APS warranty valid.

At AutoPowerSource, we stand behind the engines we sell — but it's equally important that they're installed the right way.

✅ Need Help?

If you have questions about installation or warranty coverage, feel free to contact our support team. We're here to help — before and after the sale.

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