🔧 Soul - Thermostat Replacement

The thermostat controls coolant flow to keep your engine at the correct temperature. Replacing it usually involves draining some coolant, removing the thermostat housing (the cover that holds the thermostat), installing a new thermostat with a new seal, then refilling and bleeding the cooling system to prevent overheating.

Difficulty Level: Intermediate | Estimated Time: 1.5-3.0 hours

---

⚠️ Safety & Precautions

• ⚠️ Never open the coolant cap on a hot engine; hot coolant can spray and burn.
• ⚠️ Support the Soul with jack stands on solid, level ground; never rely on a floor jack.
• ⚠️ Keep coolant off belts and electrical connectors, and clean spills immediately (coolant is toxic).
• ⚠️ Battery disconnect is not required, but keep tools clear of the radiator fan (it can turn on unexpectedly).

---

🔧 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
• Trim clip removal tool
• Flat screwdriver
• Hose clamp pliers
• Ratchet
• 10mm socket
• 12mm socket
• 6-inch socket extension
• Torque wrench (5–60 Nm range)
• Plastic gasket scraper
• Shop rags

---

🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Engine thermostat - Qty: 1
• Thermostat seal/O-ring (or thermostat housing gasket) - Qty: 1
• Coolant (Hyundai/Kia long-life, phosphate OAT compatible) - Qty: 2 gallons premix
• Distilled water - Qty: 1 gallon (if using concentrate coolant)

---

📋 Before You Begin

• Park on level ground, set the parking brake, and install wheel chocks.
• Let the engine cool completely (overnight is best).
• Set the cabin heat to HOT (this helps coolant circulate through the heater core during bleeding).
• Take a quick photo of hose routing first.

---

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Raise the front safely

• Use a floor jack to lift the front of the Soul at the front center jacking point.
• Place jack stands under the front pinch welds/subframe points and lower onto them.

Step 2: Remove the lower splash shield (if equipped)

• Use a trim clip removal tool and 10mm socket to remove the clips/bolts.
• Set the shield and fasteners aside.

Step 3: Drain coolant to below thermostat level

• Place a drain pan (at least 2-gallon) under the radiator drain area.
• Slowly loosen the coolant cap (radiator cap or reservoir cap, depending on your layout) by hand to relieve any residual pressure.
• Open the radiator drain cock using a flat screwdriver (if slotted) and drain about 1–2 gallons, or until the radiator level is low enough to prevent a major spill when the housing opens.
• Close the drain cock by hand snug (do not over-tighten).
• Keep the drain pan centered—coolant streams can shift.

Step 4: Remove the intake ducting for access

• Use a flat screwdriver to loosen the hose clamps on the intake duct.
• Use a 10mm socket to remove any air box/duct bolts (if present), then lift the ducting out of the way.

Step 5: Locate the thermostat housing

• Follow the upper radiator hose to where it meets the engine—this connection usually leads to the thermostat housing (the metal/plastic cover that holds the thermostat).
• Place shop rags under the housing to catch drips.

Step 6: Remove the radiator hose from the thermostat housing

• Use hose clamp pliers to compress the spring clamp and slide it back on the hose.
• Twist the hose gently by hand to break it loose, then pull it off.
• Do not pry on the radiator neck.

Step 7: Remove the thermostat housing

• Use a 10mm socket (sometimes 12mm socket) with a ratchet and 6-inch socket extension to remove the thermostat housing bolts.
• Carefully separate the housing—coolant may spill, so keep the drain pan ready.
• Remove the thermostat and the old seal/O-ring.

Step 8: Clean the sealing surfaces

• Use a plastic gasket scraper and shop rags to clean the mating surfaces.
• Do not gouge aluminum surfaces, and do not let debris fall into the opening.

Step 9: Install the new thermostat and seal

• Install the new thermostat in the same orientation as the old one.
• Install the new seal/O-ring (an O-ring is a rubber sealing ring that prevents leaks).
• Reinstall the housing and start the bolts by hand to avoid cross-threading.
• Use a torque wrench (5–60 Nm range) to tighten the housing bolts evenly in a crisscross pattern: Torque to OEM specification.
• Even tightening helps prevent leaks.

Step 10: Reinstall the radiator hose and intake ducting

• Push the hose fully onto the housing neck.
• Use hose clamp pliers to reposition the clamp back to its original spot.
• Reinstall intake ducting using a 10mm socket and tighten the clamps with a flat screwdriver.

Step 11: Refill coolant

• Lower the vehicle if you prefer, or keep it level on stands.
• Use a funnel to refill the system with the correct Hyundai/Kia long-life coolant (premix, or concentrate mixed with distilled water).
• Fill to the radiator neck (if equipped) and/or to the reservoir “FULL” line.

Step 12: Bleed air from the cooling system

• Start the engine and let it idle with the heater set to HOT and the fan on low.
• Watch the coolant level and add as needed using a funnel.
• As the engine warms up, the thermostat will open and the coolant level may drop—top off as needed.
• When you get steady heat from the vents and no more bubbles appear, install the cap securely.
• Air pockets can cause overheating—take your time.

Step 13: Reinstall the splash shield

• Use a 10mm socket and trim clip removal tool to reinstall the shield and clips.

---

✅ After Repair

• With the engine running, check around the thermostat housing and hose connection for leaks using a bright light and shop rags.
• Take a 10–15 minute test drive while watching the temperature gauge.
• Let the engine cool completely, then recheck the reservoir level and top off if needed.
• Dispose of old coolant properly (most parts stores accept used coolant).

---

💰 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 1.5-3.0 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.