Apologize if overlooked an existing thread with related information. Did search and did not locate any additional information for the following;

Interested in replacing the Water pump (IS350), and wanted to confirm any additional parts to consider changing the same time while replacing the following;
- Water Pump (part 16100-39436)
- Water pump bolt x2 (part16193-31080)
- Water Pump bolt x 5 (part 91551-80622)
- TOYOTA threebound thread sealant (part 1344) OR 1360
- Thermostat (part 16031-31020)
- Serpentine Belt (part 99367-K1550)

 

The IS250 guide is the same guide for the 350, only difference is the water pump part number may be different (I don't think it is, but I don't remember exactly). https://www.clublexus.com/forums/is-...the-is250.html

You don't need the bolts, reuse your old bolts. As for threadlocker, you can just use Loctite 242 that is readily available at your hardware stores. You don't really need to change the thermostat, but if you absolutely want to, you may need more than 2 gallons of coolant. The job itself is relatively easy, just keep track of where you pull the bolts from.

 

Thanks for the follow up Zmon and providing the link.
Apologies for not previously stating, I intend to change / drain the coolant (002772-SLLC2 -TOYOTA Super Long Life coolant 50/50 mix), while replacing the water pump.
Permatex representative suggested using Permatex High Performance Thread Sealant 56521, even though not an exact match to the Toyota Adhesive 1344.
Did locate Threebond 1360 Medium Strength / High -Temperature type thread lock.

Water pump part 16100-39436, does state for IS250 as well.

 

If you want to be on the safe side, grab 3 gallons of SLLC. Capacity of the system is 2 gallons iirc, but I think I needed 3 gallons of the stuff since I did another drain/refill a few weeks after when I did my water pump a few years ago.

 

The permatex thread sealant worked perfectly when I did my IS350Cs water pump.

 

While at it, replace the all the hoses for a piece of mind. Also check the pulley for play or noise.

 

Thank you Yamehoo! Overlooked the most obvious part;

Part 16571-31170 (Upper radiator hose) / CONTINENTAL 66225
Part 16572-31250 (Lower radiator hose) / CONTINENTAL 66226

 

Another thing is upgrade your hose clamps to some constant tension style. The last thing you'd want is the hoses to pop off. Not saying they will using OEM, but you'd need the proper tool. Worm clamps don't apply even pressure.

 

Another easily overlooked item! (part 90466-A0026) thanks MikeFig82! Would you know the diameter of the OEM clamp?
Who is the manufacturer of the pictured constant tension clamp?

 

I don't know the measurements of the hoses. You can get info online. Normally it should state the inside diameter of the hose. Guesstimate addition about .125" for wall thickness. Once you know the range to look for in the clamp size. My last set I purchased was from rockauto.com they're 316 SS.

 

Thanks again Mike.

 

Though pictured above, it was not mentioned. The "radiator" cap might want to be replaced. Many, including myself, have found theirs over time have separated and are in pieces just sitting inside the housing there.

Also, if yours leaks, think about a replacement overflow cap for the overflow tank.

 

Thank for pointing that out Gville350. I included the cap (part 16401-31650) in the photo to reference along with the hoses, but forgot. Thanks for pointing out the overflow cap (part 16405-31040 ???). Will add both to parts list.

 

While your at it. Don't forget to clean between the radiator and condensor core. A garden hose back flush does wonders but you could end up debris trapped at the bottom.

 

i would replace the radiator while you are doing the water pump