Assumption: Your RDX uses the Honda/Acura J35 V6 with a timing-belt-driven water pump (common on this model). Water pump replacement is done as part of a timing belt service.

🔧 RDX - Water Pump Replacement

On your RDX, the water pump sits behind the timing belt covers and is driven by the timing belt. To replace it, you remove the accessory belt and crank pulley, open the timing area, remove the timing belt, then swap the pump and reseal it.

Difficulty Level: Advanced | Estimated Time: 5-8 hours

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⚠️ Safety & Precautions

• ⚠️ Work on a cold engine only; hot coolant can burn.
• ⚠️ Support the engine before removing the right-side engine mount; an unsupported engine can drop suddenly.
• ⚠️ Never rotate the crankshaft/camshafts with the timing belt removed unless instructed; valve timing can be lost.
• ⚠️ Use jack stands on solid, level ground; never rely on a floor jack alone.
• ⚠️ Keep fingers/tools clear when releasing the timing belt tensioner; it can snap.
• 🔋 Recommended: disconnect the negative battery terminal to prevent accidental cranking.

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🔧 Required Tools

You'll need the following tools for this repair:

• Safety glasses
• Nitrile gloves
• Floor jack (rated 3-ton minimum)
• Jack stands (rated 3-ton minimum)
• Wheel chocks
• Drain pan (at least 10-quart)
• Funnel
• Plastic trim clip removal tool
• 3/8" drive ratchet
• 1/2" drive breaker bar
• Torque wrench (10-80 ft-lbs range)
• Torque wrench (50-250 ft-lbs range)
• Socket set (8mm-22mm)
• Wrench set (10mm-19mm)
• Phillips screwdriver
• Flathead screwdriver
• 19mm socket
• 22mm socket
• Serpentine belt tool (specialty)
• Crank pulley holding tool for Honda/Acura (specialty)
• Harmonic balancer puller (specialty)
• Engine support bar (specialty)
• Hydraulic press pin or sturdy bench vise (specialty)
• Shop towels
• Gasket scraper (plastic)
• Flashlight

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Water pump - Qty: 1
• Water pump gasket / O-ring (as equipped) - Qty: 1
• Timing belt - Qty: 1
• Timing belt tensioner (hydraulic) - Qty: 1
• Timing belt idler pulley - Qty: 1
• Timing belt tensioner pulley - Qty: 1
• Serpentine drive belt - Qty: 1
• Engine coolant (Honda/Acura Type 2 compatible) - Qty: 2 gallons
• Crankshaft pulley bolt (recommended replacement) - Qty: 1
• RTV silicone sealant (sensor-safe) - Qty: 1

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📋 Before You Begin

• Park on level ground, set the parking brake, and chock the rear wheels.
• Let the engine cool completely (ideally overnight).
• Disconnect the negative battery cable using a 10mm socket.
• Lift the front of the vehicle with a floor jack and support it with jack stands.
• Remove the right-front wheel using a 19mm socket.
• Remove the right inner fender liner/splash shield fasteners using a plastic trim clip removal tool and Phillips screwdriver.
• Pro tip: Take photos before each cover/bracket.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Drain the coolant

• Place a drain pan (at least 10-quart) under the radiator.
• Open the radiator cap slowly (only when cool).
• Open the radiator drain plug (petcock) by hand or with a flathead screwdriver if needed, and drain coolant fully.

Step 2: Remove the serpentine (accessory) belt

• Use a serpentine belt tool (specialty) (a long handled tool for rotating the belt tensioner) to rotate the tensioner and slip the belt off.
• Remove the belt from all pulleys and set it aside (replacement recommended).

Step 3: Support the engine and remove the right engine mount

• Set up an engine support bar (specialty) across the fenders and lightly support the engine from above (this holds the engine up when the mount is removed).
• Remove the mount bolts/nuts using a socket set (8mm-22mm) and wrench set (10mm-19mm).
• On reassembly, typical mount fasteners are Torque to 64 Nm (47 ft-lbs) for mount-to-body fasteners and Torque to 54 Nm (40 ft-lbs) for bracket fasteners (verify for your exact fastener locations).

Step 4: Remove the crankshaft pulley (harmonic balancer)

• Install the crank pulley holding tool for Honda/Acura (specialty) to keep the pulley from turning.
• Use a 22mm socket with a 1/2" drive breaker bar to loosen the crank bolt (this bolt is very tight).
• If the pulley is stuck, use a harmonic balancer puller (specialty) to remove it.
• On reassembly, a common spec for the crank bolt is Torque to 245 Nm (181 ft-lbs) (verify; many Honda/Acura J35 applications are in this range).

Step 5: Remove the timing belt covers

• Remove the upper and lower timing covers using a 10mm socket and 3/8" drive ratchet.
• Keep bolts grouped by cover location; lengths can differ.

Step 6: Set engine to Top Dead Center (TDC)

• Use a 19mm socket and 3/8" drive ratchet (or 1/2" drive breaker bar) on the crank to rotate the engine clockwise.
• Align the crank and cam timing marks to their reference marks on the engine.
• TDC means cylinder #1 is at the top of its compression stroke; timing marks line up when you’re there.

Step 7: Remove the timing belt tensioner and timing belt

• Remove the hydraulic tensioner bolts using a 12mm socket.
• Remove the timing belt from the cam and crank sprockets carefully.
• If reusing (not recommended), mark belt direction with a marker (use shop towels to keep clean).
• On reassembly, typical hydraulic tensioner bolt spec is Torque to 22 Nm (16 ft-lbs) (verify).

Step 8: Remove idler/tensioner pulleys (recommended)

• Remove the idler and tensioner pulleys using a socket set (8mm-22mm) and 3/8" drive ratchet.
• On reassembly, common pulley bolt specs are Torque to 54 Nm (40 ft-lbs) for the idler and Torque to 44 Nm (33 ft-lbs) for the tensioner pulley (verify).

Step 9: Remove the water pump

• Place the drain pan (at least 10-quart) under the water pump area; more coolant will drain.
• Remove water pump bolts using a 10mm socket and 3/8" drive ratchet.
• Gently pry the pump free if needed using a flathead screwdriver (light pressure only).
• Clean the mating surface with a gasket scraper (plastic) and shop towels until it’s smooth and dry.

Step 10: Install the new water pump

• Install the new gasket/O-ring on the new pump (light coolant film helps an O-ring seat).
• If your pump uses RTV at specific corners, apply a very small bead of RTV silicone sealant (sensor-safe) only where required.
• Install the pump and hand-start all bolts.
• Tighten evenly using a torque wrench (10-80 ft-lbs range): Torque to 12 Nm (9 ft-lbs) for water pump bolts (verify; do not overtighten into aluminum).

Step 11: Reinstall pulleys, timing belt, and set tension

• Reinstall the idler and tensioner pulleys using a torque wrench (10-80 ft-lbs range) to the specs listed earlier.
• Route the new timing belt over the crank sprocket and cam sprockets with timing marks still aligned.
• Install the hydraulic tensioner using a 12mm socket, then Torque to 22 Nm (16 ft-lbs) (verify).
• If the tensioner is new, it should come pinned. If you must compress it, use a hydraulic press pin or sturdy bench vise (specialty) very slowly (over several minutes) to re-pin it. This is a hydraulic part; rushing can damage it.
• Once everything is aligned, pull the tensioner pin to apply belt tension.
• Rotate the engine clockwise two full turns using a 19mm socket, then re-check that all timing marks still line up.

Step 12: Reassemble timing covers, crank pulley, mount, and belt

• Reinstall timing covers using a 10mm socket.
• Reinstall the crank pulley and crank bolt using a crank pulley holding tool for Honda/Acura (specialty), 22mm socket, and torque wrench (50-250 ft-lbs range): Torque to 245 Nm (181 ft-lbs) (verify).
• Reinstall the right engine mount using a socket set (8mm-22mm) and torque fasteners: Torque to 64 Nm (47 ft-lbs) and Torque to 54 Nm (40 ft-lbs) where applicable (verify per fastener size/location).
• Install the new serpentine belt using a serpentine belt tool (specialty) and confirm it sits in every pulley groove.
• Reinstall the fender liner with a plastic trim clip removal tool and Phillips screwdriver.
• Reinstall the wheel using a 19mm socket. Typical wheel lug torque is Torque to 108 Nm (80 ft-lbs).

Step 13: Refill and bleed the cooling system

• Close the radiator drain plug.
• Refill with Engine coolant (Honda/Acura Type 2 compatible) using a funnel.
• Start the engine and let it idle with the heater set to HOT. Watch coolant level and top off as air purges.
• When the radiator fan cycles and heat is steady, shut the engine off and let it cool, then recheck the coolant level and add as needed.

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✅ After Repair

• Check for leaks around the water pump area and under the vehicle after the first warm-up.
• Listen for unusual whining/chirping near the timing cover area; that can indicate belt misrouting or a pulley issue.
• Recheck coolant level the next morning (cold) and top off the reservoir to the MAX line.
• If the engine runs rough, misfires, or the check engine light appears, shut it off and re-check timing marks before driving.

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💰 DIY vs Shop Cost

Shop Cost: $900-$1,600 (parts + labor)

DIY Cost: $220-$550 (parts only)

You Save: $680-$1,050 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 5-8 hours.

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🎯 Ready to get started?

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