🔧 Timing Chain - Replacement

Your Yaris does not use a timing belt. It uses a timing chain, which is inside the engine and is not a routine maintenance item like a belt. Replacing it is a major repair because the front of the engine must come apart and the cam/crank timing must be set exactly.

Difficulty Level: Advanced | Estimated Time: 8-12 hours

---

⚠️ Safety & Precautions

• Disconnect the negative battery cable before starting.
• Support the engine before removing the right-side engine mount.
• Do not rotate the crankshaft or camshafts independently once the chain is removed.
• Keep fingers clear of the chain, sprockets, and tensioner area.
• Drain engine oil and coolant before opening the timing cover area.
• Use care around sealants and hot engine parts if the engine was recently run.

---

🔧 Required Tools

You'll need the following tools for this repair:

• Metric socket set
• Metric wrench set
• Torque wrench
• Breaker bar
• Crankshaft pulley holding tool (specialty)
• Harmonic balancer puller (specialty)
• Engine support bar
• Floor jack (rated 3-ton minimum)
• Jack stands
• Drain pan
• Plastic scraper
• Pick tool set
• Seal driver or suitable installer
• Shop rags
• Safety glasses
• Mechanic gloves

---

🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Timing chain kit - Qty: 1
• Timing chain tensioner - Qty: 1
• Timing chain guides - Qty: 1 set
• Front crankshaft seal - Qty: 1
• Timing cover gasket or sealant - Qty: 1
• Valve cover gasket - Qty: 1
• Engine oil - Qty: 4-5 quarts
• Oil filter - Qty: 1
• Coolant - Qty: 1 gallon
• Accessory drive belt - Qty: 1
• Crankshaft pulley bolt - Qty: 1

---

📋 Before You Begin

• Park on level ground and set the parking brake.
• Let the engine cool fully before starting.
• Disconnect the negative battery cable.
• Raise the front of the vehicle and support it securely on jack stands.
• Drain engine oil and coolant into clean drain pans.
• Have the replacement timing marks or service diagram ready before disassembly.

---

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Disconnect power and prep the engine bay

• Use a wrench to disconnect the negative battery terminal.
• Remove the engine cover and air intake components that block access.
• Label every connector and hose.

Step 2: Drain fluids

• Use a drain pan to drain the engine oil.
• Use a second drain pan to drain the coolant.
• Reinstall the drain plugs loosely to keep dirt out.

Step 3: Remove accessory drive components

• Use the appropriate metric socket set to remove the accessory drive belt and related brackets.
• Remove the crankshaft pulley bolt using a breaker bar and crankshaft pulley holding tool.
• Use a harmonic balancer puller to remove the crank pulley.

Step 4: Support the engine and remove the mount

• Place an engine support bar above the engine and take the weight off the right-side mount.
• Use the metric socket set to remove the engine mount bolts.
• Lift the mount out carefully.

Step 5: Remove the timing cover

• Use the metric socket set to remove all timing cover bolts.
• Gently separate the cover with a plastic scraper.
• Do not pry hard against the aluminum housing.

Step 6: Set engine to top dead center

• Use a socket and ratchet on the crankshaft bolt to turn the engine by hand.
• Line up the crank and cam timing marks exactly as shown in the service diagram.
• Turn only by hand.

Step 7: Remove the timing chain components

• Use a pick tool to remove the timing chain tensioner.
• Remove the chain guides with the metric socket set.
• Slip the timing chain off the sprockets carefully.

Step 8: Install the new chain and guides

• Install the new chain using the timing marks on the chain and sprockets.
• Install the new guides with the metric socket set.
• Install the new tensioner and release it after confirming timing alignment.
• Torque to manufacturer specification using the torque wrench.

Step 9: Replace seals and reseal the cover

• Use a pick tool to remove the old crankshaft seal.
• Install the new seal with a seal driver.
• Apply timing cover sealant or install the gasket as required.
• Reinstall the timing cover and tighten bolts evenly with a torque wrench.
• Torque to manufacturer specification using the torque wrench.

Step 10: Reassemble the front of the engine

• Reinstall the engine mount and tighten with a torque wrench.
• Reinstall the crankshaft pulley and crank bolt.
• Reinstall the accessory drive belt and removed brackets.
• Torque to manufacturer specification using the torque wrench.

Step 11: Refill fluids and verify timing

• Refill engine oil and coolant.
• Reconnect the battery.
• Crank the engine by hand again if needed to confirm smooth rotation before starting.

---

✅ After Repair

• Start the engine and listen for abnormal chain noise.
• Check for oil or coolant leaks at the timing cover and crank seal.
• Verify idle quality and engine response.
• Recheck fluid levels after a short test drive.

---

💰 DIY vs Shop Cost

Shop Cost: $1,200-$2,200 (parts + labor)

DIY Cost: $250-$600 (parts only)

You Save: $950-$1,600 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 8-12 hours.

---

🎯 Ready to get started?

HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.