How to Replace the Upper & Lower Radiator Hoses on a 2018 Acura MDX
Step-by-step coolant hose replacement with tools, parts list, refill/bleed tips, and leak checks for 2016, 2017, 2018, 2019, 2020
How to Replace the Upper & Lower Radiator Hoses on a 2018 Acura MDX
Step-by-step coolant hose replacement with tools, parts list, refill/bleed tips, and leak checks for 2016, 2017, 2018, 2019, 2020
🔧 MDX - Radiator Hose Replacement
Replacing a radiator hose fixes coolant leaks and prevents overheating. On your MDX there are typically two main radiator hoses: the upper hose (radiator to engine) and the lower hose (radiator to engine/water pump area).
Difficulty Level: Intermediate | Estimated Time: 1.0-2.0 hours
⚠️ Safety & Precautions
- ⚠️ Never open the radiator cap on a hot engine; coolant can spray and burn you.
- ⚠️ Support the MDX with jack stands if you lift it; never rely on a jack.
- ⚠️ Keep coolant off belts and electrical connectors; wipe spills immediately.
- ⚠️ Coolant is toxic—use a drain pan and keep away from kids/pets.
- Battery disconnect is not required for this repair.
🔧 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)
- Hose clamp pliers
- Channel-lock pliers
- Pick tool (hook pick)
- Trim clip removal tool
- Phillips screwdriver
- Flathead screwdriver
- 10mm socket
- 12mm socket
- 3/8" drive ratchet
- 3/8" drive extension (6")
- Torque wrench (3/8" drive)
- Funnel with long neck
- Shop towels
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Upper radiator hose - Qty: 1
- Lower radiator hose - Qty: 1
- Hose clamps - Qty: 2-4
- Engine coolant (Honda/Acura Type 2, premixed) - Qty: 2-4 quarts
📋 Before You Begin
- Park on level ground, set the parking brake, and let the engine cool completely (ideally overnight).
- Set the HVAC to HI heat (this helps coolant flow through the heater core during bleeding).
- If you need more room for the lower hose, raise the front and support with jack stands.
- Place a drain pan under the radiator hose area to catch coolant.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Remove the radiator cap (only when cold)
- Use your hand to slowly loosen the radiator cap to the first stop to release any leftover pressure, then remove it fully.
- If your MDX uses a cap on the coolant reservoir only, remove the reservoir cap instead.
Step 2: Make access (upper hose vs lower hose)
- Upper hose: Usually accessible from the top with the hood open.
- Lower hose: Use a floor jack (rated 3-ton minimum) and jack stands (rated 3-ton minimum) for access from below; use a trim clip removal tool, 10mm socket, and Phillips screwdriver to remove any lower splash shield panels blocking access.
Step 3: Slide the hose clamps back
- Use hose clamp pliers to compress the clamp and slide it 2-3 inches back on the hose.
- If the clamp is a worm-gear style, loosen it with a flathead screwdriver (or 8mm socket if applicable).
- Clamp ears are sharp; wear gloves.
Step 4: Break the hose free (don’t yank)
- Twist the hose gently by hand to break the seal.
- If it’s stuck, carefully work around the hose end with a pick tool (hook pick) to let air in between the hose and the fitting.
- Use channel-lock pliers only on the hose end if needed, and squeeze lightly (you don’t want to crush the radiator neck).
Step 5: Remove the hose and catch coolant
- Pull the hose off the radiator end first and aim it into the drain pan (at least 10-quart).
- Remove the hose from the engine-side fitting and let coolant drain.
- Use shop towels to wipe any spills.
Step 6: Inspect the fittings and clean the sealing surfaces
- Check the radiator neck and engine-side pipe for cracks, heavy corrosion, or deep pitting.
- Use shop towels to clean the sealing area until it’s smooth and dry.
Step 7: Install the new hose and position the clamps
- Slide the clamps onto the new hose first (use hose clamp pliers).
- Push the hose fully onto each fitting until it bottoms out.
- Position each clamp behind the raised “bead” on the fitting, then release/tighten it.
- Torque to: If using worm-gear clamps, tighten with a flathead screwdriver until snug and the hose cannot rotate by hand (hose clamps typically do not have a factory torque spec).
Step 8: Reinstall any splash shields (lower hose)
- Use a 10mm socket, Phillips screwdriver, and trim clip removal tool to reinstall the underbody panel(s).
Step 9: Refill coolant
- Insert a funnel with long neck into the radiator fill neck (or reservoir if that is the fill point).
- Add Honda/Acura Type 2 premixed coolant until full.
- Fill the overflow reservoir to the MAX line.
Step 10: Bleed air from the cooling system
- Start the engine and let it idle with the radiator cap off (or reservoir cap off if that’s the fill point).
- Turn the heater to HI and fan to a medium setting.
- Watch for air bubbles and the coolant level dropping; keep topping up using the funnel with long neck.
- Once the radiator fan cycles on and off and bubbles slow down, reinstall the cap by hand.
- Don’t rev hard; idle is safer for bleeding.
Step 11: Final checks for leaks
- With the engine warm, inspect both hose ends using safety glasses and a light.
- Look for seepage around the clamp areas and check for coolant smell or drips under the MDX.
✅ After Repair
- Let the engine cool completely, then recheck the coolant level in the reservoir and top off if needed.
- Take a 10-15 minute test drive while monitoring the temperature gauge.
- Recheck for leaks after the drive and again the next morning.
- If the temperature rises, the heater blows cold, or you hear gurgling, shut it off and re-bleed (air is still trapped).
💰 DIY vs Shop Cost
Shop Cost: $250-$550 (parts + labor)
DIY Cost: $40-$140 (parts only)
You Save: $210-$410 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1.0-2.0 hours.
🎯 Ready to get started?
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