🔧 Timing Chain - Replacement

Assumption: Your Explorer 3.5L does not use a timing belt. It uses timing chains, so the correct repair is timing chain service. This is a major engine teardown job and small mistakes can cause severe engine damage.

Difficulty Level: Advanced | Estimated Time: 12-18 hours

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⚠️ Safety & Precautions

• Disconnect the negative battery cable before starting.
• Support the vehicle securely on jack stands if you raise it. Jack stands are rigid supports that hold the vehicle up safely.
• Let the engine cool completely before touching the cooling system or front cover.
• Mark and keep track of every bolt and bracket. Many are different lengths.
• Use care around the cam phasers and timing components. Incorrect timing can bend valves.
• Replace the engine oil and filter after the repair.

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🔧 Required Tools

You'll need the following tools for this repair:

• Socket set metric 8mm-21mm
• 1/2-inch drive ratchet
• Breaker bar
• Torque wrench
• Torque angle gauge
• Harmonic balancer puller (specialty)
• Camshaft holding tool set (specialty)
• Timing chain alignment kit (specialty)
• Serpentine belt tool
• Drain pan
• Floor jack (rated 3-ton minimum)
• Jack stands
• Safety glasses
• Nitrile gloves
• Scraper
• Pry bar
• Shop rags

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Timing chain kit - Qty: 1
• Timing chain tensioners - Qty: 1 set
• Timing chain guides - Qty: 1 set
• Cam phaser(s) - Qty: As needed
• Timing cover gasket set - Qty: 1
• Crankshaft front seal - Qty: 1
• Valve cover gaskets - Qty: 1 set
• Engine oil (spec per owner’s manual) - Qty: 6 quarts
• Oil filter - Qty: 1
• Coolant - Qty: 1-2 gallons
• Accessory drive belt - Qty: 1
• Timing cover sealant - Qty: 1

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📋 Before You Begin

• Park on level ground and set the parking brake.
• Disconnect the negative battery cable.
• Drain the coolant and engine oil.
• Remove the front splash shield and right front wheel if needed for access.
• Set the engine to top dead center on cylinder 1 before disassembly.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Remove accessory drive components

• Use the serpentine belt tool to release belt tension and remove the accessory belt.
• Use the socket set metric 8mm-21mm to remove the alternator, brackets, and any front accessories blocking the timing cover.
• Keep bolts in labeled rows.

Step 2: Remove crankshaft pulley

• Use the socket set metric 8mm-21mm and breaker bar to remove the crankshaft pulley bolt.
• Use the harmonic balancer puller (specialty) to remove the crankshaft pulley.

Step 3: Remove valve covers and timing cover

• Use the socket set metric 8mm-21mm to remove both valve covers.
• Use the socket set metric 8mm-21mm to remove the timing cover bolts.
• Carefully separate the timing cover with a pry bar if needed.
• Clean the sealing surfaces with a scraper.

Step 4: Lock the engine at top dead center

• Rotate the crankshaft by hand with the socket set metric 8mm-21mm until cylinder 1 is at top dead center.
• Install the camshaft holding tool set (specialty) and timing chain alignment kit (specialty) to lock timing in place.
• Do not rotate the engine once locked.

Step 5: Remove timing components

• Use the socket set metric 8mm-21mm to remove timing chain guides and tensioners.
• Remove the timing chains and cam phasers as needed.
• Inspect sprockets, guides, and phasers for wear or damage.

Step 6: Install new timing components

• Install the new timing chains using the timing chain alignment kit (specialty).
• Install new guides and tensioners with the socket set metric 8mm-21mm.
• Install cam phasers and tighten all fasteners to factory specification.
• Double-check all timing marks.

Step 7: Reinstall timing cover and front components

• Apply the correct timing cover sealant where specified by the service procedure.
• Install the new timing cover gasket set and crank seal.
• Reinstall the timing cover and tighten bolts to factory specification with the torque wrench.
• Reinstall the crankshaft pulley and tighten the crank bolt to factory specification using the torque wrench and torque angle gauge.

Step 8: Reassemble accessories and refill fluids

• Reinstall brackets, accessories, and the accessory belt using the socket set metric 8mm-21mm and serpentine belt tool.
• Install the new valve cover gaskets and valve covers.
• Refill engine oil, engine filter, and coolant.

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✅ After Repair

• Reconnect the battery.
• Crank the engine and listen for abnormal chain noise.
• Check carefully for oil or coolant leaks around the timing cover and valve covers.
• Clear any stored fault codes with a scan tool if needed.
• Run the engine to full operating temperature and recheck fluid levels.

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💰 DIY vs Shop Cost

Shop Cost: $2,500-$4,500 (parts + labor)

DIY Cost: $500-$1,200 (parts only)

You Save: $1,300-$3,300 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 12-18 hours.

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🎯 Ready to get started?

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