Prius Water Pump

For a 2008 Prius engine water pump, the good news is: you don’t need anything exotic. It’s mostly basic hand tools—but a couple sizes and extensions really matter because space is tight.

Here’s a realistic, mechanic-level tool list based on actual Prius jobs:

🔧 Core tools (you absolutely need)

These are the main ones you’ll use on almost every bolt:

• 10mm socket (VERY important – most bolts)

• 12mm socket (a few brackets/mounts)

• 3/8” drive ratchet

• Socket extensions (short + medium)

• 10mm wrench (box or ratcheting)

👉 The inverter pump procedure (same generation Prius) specifically calls out 10mm + 12mm sockets, ratchet, extensions 

🔧 Highly recommended (makes life easier)

These aren’t optional in practice unless you enjoy frustration:

• Swivel / universal joint adapter

• Flex-head ratcheting wrench (10mm)

• Long extension (for awkward angles)

• Torque wrench (3/8”) – for proper reassembly

From real-world experience:

“10 mm flex head wrench… long reach wrench… extension… tight space”

🔧 Supporting tools (coolant + removal)

• Drain pan (you’ll lose coolant)

• Hose clamp pliers (or regular pliers)

• Flat screwdriver or pick (for hose removal)

• Trim clip tool (if removing plastic covers)

• Gloves + safety glasses

🔧 Situational (depends on how deep you go)

Sometimes needed on the engine water pump (belt-driven):

• Serpentine belt tool or breaker bar (to relieve tension)

• Jack + wood block (to slightly support engine if clearance is tight)

🧠 Key insight (this matters)

• Most of the pump bolts are 10mm → that’s your main size

• Tight access is the real challenge—not bolt size

• You’ll spend more time dealing with clearance and angles than force

⚠️ One important clarification

Your 2008 Prius actually has two different pumps:

• Engine water pump (belt-driven) ← what you’re asking about

• Inverter coolant pump (electric) ← easier job

They use similar tools, but:

• Engine pump may require belt removal + more clearance work

• Inverter pump is more straightforward

✔️ Simple “minimum kit” if you’re buying tools

If you want the bare minimum that will actually work:

• 10mm socket (deep + shallow)

• 12mm socket

• 3/8” ratchet

• 6” extension

• Flex-head 10mm wrench

• Drain pan

If you want, I can  walk you step-by-step through the job (including where it gets tricky on the Prius specifically).