When to replace water pump

If it ain't broke don't fix it.
It was a loose radiator cap. Keep an eye on your coolant level and possible leakage underneath and your ears on noises.

 

I wouldn't be surprised. Mine was leaking at 149k. If you look underneath, you'll see a pink crust where any leaks have dried. You'll probably have to flex some of the plastic away to see up there. I don't know for a fact, but have heard that that crust can partly close off a leak until the leak gets bad enough and then let go and suddenly become a much bigger leak. Then again, you might be ok for lots more miles. It's a bit of a crap shoot, I think.

 

Replacing items before they need to be replaced isn't.........efficient, so MY answer to the question is, "when it fails."

Water pumps usually do not fail catastrophically.
There will usually be some leakage (tattletale leak) or a whirring sound from the pump before it goes Tango-Uniform, so you can look and listen for that.
Cars are going beltless these days, so the above statement might not apply.

Since the soulless nebbishes at Toyota do not think that you need a temperature gauge, I would strongly recommend that you immediately drop out of warp if you have indications that things down in the engine room are getting warm.

Warp coils aren't cheap.


How did your radiator cap get "loose?"

 

FYI, coolant is important to an engine.
Water pump is important. You don't want your car to overheat all the time.
You could end up with a cracked head after a 100 miles.
We got ours replaced on the 05 and it cost us $350 parts and labor.
Or $4,000 for a new engine without labor.
Good luck.


Posted via the PriusChat mobile app.

 

Doc,

If the waterpump had been the cause (impellers broken/worn/loose) it would not have heat NOW, because they did not replace it.

Now, it is possible that the WP seal is leaking/weeping and the coolant loss caused the circulation system to become inefficient and/or have air trapped in it. If there is evidence of coolant on the WP seal area, replace it NOW.

Barring any of the above, where did the coolant go that allowed air into the system and who took the cap loose????? These cars have a "degas bottle" between the rad and engine, THAT is the ONLY place one needs to check/add coolant to the vehicle unless the system is breached.

 

I replaced the ICE water pump at 190,000 miles in my 2008 Prius pre-emptively because I had an upcoming trip approaching and that amount of mileage is an accomplishment, in my experiences with water pumps previously. With me, this critical engine part has failed me at the worst possible times- without much notice. If you change it, make sure it's a genuine Toyota water pump-- not some Chinese knock-off. I kept the old one as a spare. The OEM part was $62.00 plus tax and the Toyota pink antifreeze concentrate was $23 a gallon. The ICE water pump is a "wear" item, as far as I'm concerned, and they do not last forever. Maybe a few Prius owners here on PC can prove me wrong on this assumption. My car was due for a coolant change and a new belt for the pump, so was a perfect time to do the job on my terms-- not because of a breakdown with possible engine damage. Once an aluminum engine is severely overheated, it is never the same.

 

Ditto. Found low coolant one day and the belt was getting questionable, so did them both. Turned out the pump was leaking, v e r y s l o w l y though.