🔧 Lancer - Radiator Hose Replacement

Replacing a radiator hose stops coolant leaks and prevents overheating. On your Lancer, there are typically two main radiator hoses (upper and lower), and the steps are very similar for either one.

Difficulty Level: Intermediate | Estimated Time: 1-2 hours

---

⚠️ Safety & Precautions

• ⚠️ Never open the radiator cap on a hot engine; hot coolant can spray and burn you.
• ⚠️ Support the car with jack stands if you lift it; never rely on a floor jack alone.
• ⚠️ Coolant is toxic; keep it away from kids/pets and clean spills immediately.
• ⚠️ If the cooling fan turns on automatically, keep hands/tools clear of the fan blades.
• 🔋 Battery disconnect is not required for this job.

---

🔧 Required Tools

You'll need the following tools for this repair:

• Safety glasses
• Nitrile gloves
• Floor jack (rated 2-ton minimum)
• Jack stands (rated 2-ton minimum)
• Wheel chocks
• Drain pan (at least 2-gallon)
• Funnel
• Spill-free coolant funnel kit (specialty)
• Hose clamp pliers (specialty)
• Channel-lock pliers
• Pick tool (small hook pick)
• Utility knife
• Flathead screwdriver
• 10mm socket
• Ratchet
• Extension (3-inch)
• Shop rags
• Flashlight

---

🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Upper radiator hose - Qty: 1
• Lower radiator hose - Qty: 1
• Radiator hose clamps - Qty: 2-4
• Mitsubishi Super Long Life Coolant (premixed) - Qty: 1-2 gallons

---

📋 Before You Begin

• Park on level ground, set the parking brake, and place wheel chocks behind the rear wheels.
• Let the engine cool fully (best is sitting overnight).
• Set the HVAC to HOT (this helps coolant circulate through the heater core during bleeding).
• Assumption: Clamp styles and exact torque specs vary; tighten clamps securely without stripping.

---

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Access the hose you’re replacing

• Open the hood and use a flashlight to locate the hose.
• Upper hose: runs from the top of the radiator to the engine/thermostat housing area.
• Lower hose: runs from the bottom of the radiator to the engine area (usually easier from underneath).
• If you need underside access, lift the front with a floor jack (rated 2-ton minimum) and support with jack stands (rated 2-ton minimum).

Step 2: Relieve pressure (engine cold only)

• Place shop rags around the radiator cap area.
• Slowly loosen the cap to the first stop to release any remaining pressure, then remove it fully.

Step 3: Drain enough coolant to get below the hose level

• Position a drain pan (at least 2-gallon) under the radiator drain area.
• If equipped with a drain cock, open it carefully by hand or with a flathead screwdriver (gentle—plastic can break).
• If there’s no easy drain access, you can drain by loosening the lower hose slightly, but expect more mess.
• Drain until coolant level is below the hose you’re removing, then close the drain.

Step 4: Remove the hose clamps

• Use hose clamp pliers (specialty) to squeeze and slide spring clamps away from the hose end.
• If you have worm-gear clamps, loosen them with a flathead screwdriver.
• Tip: Take a photo before removing anything.

Step 5: Remove the old radiator hose

• Twist the hose gently by hand to break it free.
• If it’s stuck, carefully work a pick tool (small hook pick) under the hose end to break the seal (do not gouge the plastic radiator neck).
• If the hose is rock-hard and won’t come off, use a utility knife to slit the hose lengthwise near the end, then peel it off carefully.

Step 6: Prep the fittings (radiator and engine necks)

• Wipe the radiator neck and engine neck with shop rags until clean and smooth.
• Inspect for cracks, pitting, or broken beads (the “lip” that helps keep the hose from sliding off).

Step 7: Install the new hose

• Slide the clamps onto the hose first (use hose clamp pliers (specialty) if spring clamps).
• Push the hose fully onto each fitting until it seats against the stop/bead.
• Reposition the clamps behind the bead/lip of the fitting.
• Tighten worm-gear clamps with a flathead screwdriver until snug and the hose can’t rotate by hand (do not crush the hose).

Step 8: Refill coolant

• Install a spill-free coolant funnel kit (specialty) on the radiator fill neck (or reservoir fill point if applicable).
• Refill with Mitsubishi Super Long Life Coolant (premixed) using a funnel until full.
• Fill the overflow reservoir to the FULL line.

Step 9: Bleed air from the cooling system

• Start the engine and let it idle.
• Set HVAC to HOT and fan to low/medium.
• Watch the coolant in the funnel: as the thermostat opens, the level may drop—add coolant as needed.
• Squeeze the upper radiator hose carefully with gloved hands to help burp trapped air (keep fingers away from belts/fans).
• When bubbles stop and heat blows hot, shut the engine off and let it cool, then top off again.

Step 10: Recheck for leaks and reassemble

• Inspect both hose ends with a flashlight while the engine is idling for any seepage.
• If you removed shields/covers, reinstall them using a 10mm socket, ratchet, and extension (3-inch).
• Lower the car safely (remove jack stands (rated 2-ton minimum) and lower with the floor jack (rated 2-ton minimum)).

---

✅ After Repair

• Test drive 10–15 minutes while watching the temperature gauge.
• Park, let it cool completely, then recheck radiator level and overflow reservoir; top off with Mitsubishi Super Long Life Coolant (premixed) if needed.
• Look under the car the next morning for any coolant drips.
• Dispose of old coolant properly (sealed container; recycling/collection center).

---

💰 DIY vs Shop Cost

Shop Cost: $250-$500 (parts + labor)

DIY Cost: $40-$150 (parts only)

You Save: $210-$350 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1-2 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.